DISTURBANCE SIGNALS

Technical Field

[0001] The present disclosure relates generally to methods, device, network node and user equipment (UE) for handling wireless disturbance signals. The present disclosure further relates to computer programs and carriers corresponding to the above methods, device, network node and UE.

Background

[0002] To meet the huge demand for higher bandwidth, higher data rates and higher network capacity, due to e.g. data centric applications, existing 4 ^th Generation (4G) wireless communication network technology, aka Long Term Evolution (LTE) is being extended or enhanced into a 5 ^th Generation (5G) technology, also called New Radio (NR) access. The following are requirements for 5G wireless communication networks:

Data rates of several tens of megabits per second should be supported for tens of thousands of users in a network covering e.g. part of a city such a e.g. a city block, an underground system, a park, an arena etc.;

1 gigabit per second is to be offered simultaneously to tens of workers on the same office floor; Several hundreds of thousands of simultaneous connections is to be supported for massive sensor deployments;

Spectral efficiency should be significantly enhanced compared to 4G;

Coverage should be improved;

Signaling efficiency should be enhanced;

Latency should be reduced significantly compared to 4G and

Ultra-reliable low-latency communication, URLLC

[0003] Fig. 1 shows a wireless communication network 100 comprising a network node 130 that is in, or is adapted for, wireless communication with a number of UEs 140, 142. The network node 130 provides radio coverage in a cell 150, which is a geographical area. The number of UEs 140, 142 resides in the cell 150.

[0004] As any wireless cellular network, such as the wireless cellular network shown in Fig. 1 , 5G networks are built upon open sharing, in which the communication medium is the free space. This typically makes them prone to interference, which is one of the fundamental causes of degradation of the performance of wireless networks. If the level of obstruction is high, the receivers of the network nodes 130 and/or the UEs 140, 142 are not able to decode the transmitted signals. This weakness can be used by some adversary nodes to cause disturbances, i.e., intentional interference and hinder legitimate users’ communication over specific wireless channels. This is well-known as jamming attacks.

[0005] Jamming attacks pose serious risks to public communication services. In the early 20 ^th century, jamming attacks were used in military battles. Nowadays, jamming attacks can be launched to hinder public communication services. Several jammer devices are available in the market at a low cost. In addition, the most sophisticated jamming attacks can be implemented with a price as low as 1 k$ using low-cost software-defined radio tools, and some primary programming skills. Furthermore, 5G is expected to be the infrastructure for emergency services, natural disasters rescue, public safety, and military communications making jamming attacks a real threat.

[0006] The burden of countering those jamming activities falls on both ends of the wireless communication link: at the Base station (BS)ZNetwork node and the mobile device/UE side. A jammer device or blocker is a device which deliberately transmits signals on the same radio frequencies as the mobile device. This disrupts the communication between the mobile device and the base station, effectively disables communication within the range of the jammer, and prevents the mobile device and/or the base station from receiving signals. Jammer devices can be used in practically any location, but sometimes in the past they have been found primarily in places where e.g., a phone call would be particularly disruptive because silence is expected, such as in entertainment venues.

[0007] Because jammer devices disrupt the operations of legitimate mobile device services, the use of such jammer devices is illegal in many jurisdictions, especially without a license. When operational, such jammer devices also block access to emergency services.

[0008] By injecting faked or replayed signals, a jammer device aims to interrupt the ongoing communication of mobile devices such as smartphones, laptops and mobile sensing robots, and even result in denial of service (DoS) attacks in wireless networks. With the pervasion of smart radio devices such as universal software radio peripherals (USRPs), smart jammer devices can cooperatively and flexibly choose their jamming policies to block the mobile devices efficiently. Jammer devices can even induce the mobile device to enter a specific communication mode and then launch the jamming attacks accordingly.

[0009] Nowadays, mobile devices and base stations usually apply spread spectrum techniques, such as frequency hopping and direct sequence spread spectrum to address jamming attacks. However, if most frequency channels in the receiver location are blocked by jammer devices and/or strongly interfered with by electric appliances such as microwaves and other communication radio devices, spread spectrum alone cannot improve the communication performance such as the signal-to-interference-plus- noise ratio (SINR) of the received signals and the bit error rate (BER) of the messages. Game theory has been applied to study power allocation for the anti-jamming in wireless communication. For instance, the Colonel Blotto anti-jamming game presented in Y. Wu, B. Wang, K. J. R. Liu and T. C. Clancy "Antijamming games in multi-channel cognitive radio networks", IEEE J. Sei. Areas Commun., vol. 30, no. 1 , pp. 4-15, Jan 2012, provides a power allocation strategy to improve the worst-case performance in the presence of jamming in cognitive radio networks. The power control Stackelberg game as presented in L. Xiao, Y. Li, J. Liu and Y. Zhao, "Power control with reinforcement learning in cooperative cognitive radio networks against jamming", J. Supercomput., vol. 71 , no. 9, pp. 3237-3257, Apr 2015 formulates the interactions among a source node, a relay node and a jammer device that choose their transmit powers in sequence without interfering with primary users. The transmission Stackelberg game developed in X. Tang, P. Ren, Y. Wang, Q. Du and L. Sun, "Securing wireless transmission against reactive jamming: A Stackelberg game framework", Proc. IEEE Global Commun. Conf., pp. 1-6, Dec. 2015 helps build a power allocation strategy to maximize the SINR of signals in wireless networks. The prospect-theory based dynamic game in L. Xiao, J. Liu, Q. Li, N. B. Mandayam and H. V. Poor, "User-centric view of jamming games in cognitive radio networks", IEEE Trans. Inf. Forensics Secur., vol. 10, no. 12, pp. 2578- 2590, Dec 2015 investigates the impact of the subjective decision-making process of a smart jammer in cognitive networks under uncertainties. The stochastic game formulated in R. El-Bardan, V. Sharma and P. K. Varshney, "Learning equilibria for power allocation games in cognitive radio networks with a jammer", Proc. IEEE Global Conf. Signal Inf. Process., pp. 1-6, Dec. 2016 investigates the power allocation of a user in the presence of a jammer under uncertain channel power gains.

[00010] Game theory has been used for providing insights into frequency channel selection in the presence of jamming. For instance, the stochastic channel access game investigated in B. Wang, Y. Wu, K. J. R. Liu and T. C. Clancy, "An anti-jamming stochastic game for cognitive radio networks", IEEE J. Sei. Areas Commun., vol. 29, no. 4, pp. 877-889, Mar 2011 helps a user to choose the control channel and the data channel to maximize the throughput in the presence of jamming. The Bayesian communication game in A. Garnaev, Y. Liu and W. Trappe, "Anti-jamming strategy versus a low-power jamming attack when intelligence of adversary's attack type is unknown", IEEE Trans. Signal Inf. Process. Over Netw., vol. 2, no. 1 , pp. 49-56, Mar 2016 studies channel selection in the presence of smart jammers with unknown types of intelligence. The zero-sum game as proposed in M. Hanawal, M. Abdelrahman and M. Krunz, "Joint adaptation of frequency hopping and transmission rate for antijamming wireless systems", IEEE Trans. Mobile Comput., vol. 15, no. 9, pp. 2247-2259, Sep 2016 investigates frequency hopping and transmission rate control to improve the average throughput in the presence of jamming. The game- theoretic anti-jamming channel selection scheme as developed in C. Chen, M. Song, C. Xin and J. Backens, "A game-theoretical anti-jamming scheme for cognitive radio networks", IEEE Netw., vol. 27, no. 3, pp. 22-27, Jun 2013 increases the payoffs of mobile users and improves the communication performance against jamming.

[00011] Reinforcement learning techniques enable an agent to achieve an optimal policy via trials in Markov decision processes. The Q-learning based power control strategy developed in L. Xiao, Y. Li, J. Liu and Y. Zhao, "Power control with reinforcement learning in cooperative cognitive radio networks against jamming", J. Supercomput., vol. 71 , no. 9, pp. 3237-3257, Apr 2015 makes a tradeoff between the defense cost and the communication efficiency without being aware of the jamming model. The Q- learning based channel allocation scheme as proposed in Y. Gwon, S. Dastangoo, C. Fossa and H. T. Kung, "Competing mobile network game: Embracing anti-jamming and jamming strategies with reinforcement learning", Proc. IEEE Conf. Comm. Netw. Security, pp. 28-36, Oct. 2013 can achieve an optimal channel access strategy for a radio transmitter with multiple channels in a dynamic game. The synchronous channel allocation approach in F. Slimeni, B. Scheers, Z. Chtourou and V. L. Nir, "Jamming mitigation in cognitive radio networks using a modified Q-learning algorithm", Proc. IEEE Int’l Conf. Military Commun. Inf. Syst., pp. 1-7, May 2015 applies Q-learning to proactively avoid using blocked channels in cognitive radio networks. The WoLF-Q based anti-jamming communication strategy as proposed in T. Chen, J. Liu, L. Xiao and L. Huang, "Anti-jamming transmissions with learning in heterogenous cognitive radio networks", Proc. IEEE Wireless Comm. Netw. Conf. Workshops/So-HetNets Workshop, pp. 293-298, Jun. 2015 selects the transmit channel ID and the transmit power to resist sweeping jamming. An anti-jamming communication scheme as developed in S. Singh and A. Trivedi, "Anti-jamming in cognitive radio networks using reinforcement learning algorithms", Proc. IEEE Int. Conf. Wireless Opt. Comm. Netw., pp. 1-5, Nov. 2012 uses the state-action-reward-action-state-action method to choose the transmit channel to increase the payoff against jamming compared with Minimax-Q. The multi-agent reinforcement learning (MARL) based channel allocation as proposed in B. F. Lo and I. F. Akyildiz, "Multiagent jamming-resilient control channel game for cognitive radio ad hoc networks", Proc. IEEE Int. Conf. Commun., pp. 1821-1826, Jun. 2012 and M. A. Aref, S. K. Jayaweera and S. Machuzak, "Multi-agent reinforcement learning based cognitive anti-jamming", Proc. IEEE Wireless Comm. Netw. Conf., pp. 1-6, May 2017 enhances the transmission and sensing capabilities for cognitive radio users. The MARL based power control strategy as developed in X. He, H. Dai and P. Ning, "Faster learning and adaptation in security games by exploiting information asymmetry", IEEE Trans. Signal Process., vol. 64, no. 13, pp. 3429-3443, Jul 2016 accelerates the learning of energy harvesting communication systems against intelligent adversaries.

[00012] The 2D anti-jamming mobile communication system proposed in G. Han, L. Xiao and H. V. Poor, "Two-dimensional anti-jamming communication based on deep reinforcement learning", Proc. IEEE Int. Conf. Acoust. Speech Signal Process., pp. 1-5, Mar. 2017 uses both frequency and spatial diversion to improve the communication performance against jamming and applies Deep Q-Network (DQN) to derive an optimal policy without knowing the jamming and interference model or the radio channel model. They present a fast DQN based power and mobile control scheme that applies the hot-booting and macro-actions techniques to accelerate learning and thus improve the jamming resistance of the communication scheme as proposed in the article above for mobile communication systems with large numbers of channels.

[00013] For communication in licensed spectrum, scheduling and even inter-BS coordination together with strict rules/requirements for avoiding unintentional transmission outside intended spectrum has been developed to avoid interference. Jamming devices deliberately or unintentionally violate such rules, disrupting normal cellular NW operation. The motivation for intentional jamming likely increases as 5G will address new critical services beyond Enhanced Mobile Broadband (e-MBB), e.g., industrial and other commercial deployments, as well as many new services, like URLLC, which will be much more sensitive to communication disruption. Some wireless communication services that require high communication reliability/availability will likely also operate in new industrial environments where different types of unintentional interference might occur. Hence, for cellular networks, a higher level of protection than today will likely be needed.

[00014] Depending on the jamming signal type and power, its impact may range from classical interfere nee- 1 ike to fully blocking the receiver front end and even causing hardware (HW) damage to the sensitive low-noise amplifier (LNA) stage. Most of classical jamming mitigation solutions, such as frequency hopping, spread spectrum, ...etc., are designed to act preemptively, potentially lowering communications efficiency or performance. Alternatively, existing jamming mitigation solutions may be activated after the jamming signal actually has affected the communication process. In such solutions, the presence of a jamming signal is detected in baseband, after it has entered the Radio frequency (RF), been down-converted and been transformed from analog to digital form. This may potentially damage or saturate critical analog stages so that no information can be extracted at least until countermeasures are applied after some detection and mode switching delays.

[00015] As shown in Fig. 2, one jamming mitigation apparatus according to some prior art includes a down-conversion and analog-to-digital converter (ADC) unit 202. This down-conversion and ADC unit 202 receives wireless signals from antennas of the UE or the network node and apply down-conversion and AD conversion to the received wireless signals. A baseband processing unit 204 receives the down- converted digital signals and perform conventional baseband processing onto them. A jamming protection unit 206 receives the processed baseband signals and perform jamming protection to them, that is, detects and removes the jamming from the signals. As stated above, the jamming protection is typically performed after down conversion by the baseband processing unit 204.

[00016] There is thus a need for a jamming protection solution that can be modular, removes jamming signals or sudden strong interference immediately before it has a chance to enter the active circuitry of the network node or the UE, and optionally does not substantially impact the spatial properties of the antenna ports of the network node or UE as seen by the baseband processing unit.

Summary

[00017] It is an object of the invention to address at least some of the problems and issues outlined above. It is possible to achieve these objects and others by using methods, network nodes and wireless communication devices as defined in the attached independent claims.

[00018] According to one aspect, a method performed by a detection device for a receiver of a wireless communication network, for handling wireless disturbance signals, the receiver comprising radio antennas is disclosed. The method comprises obtaining antenna domain analog radio signals from the antennas and transforming the obtained antenna domain analog radio signals from antenna domain into spatial domain using a passive hardware transforming unit. The method further comprises converting the spatial domain analog radio signals into spatial domain digital baseband signals and determining a signal strength level of each of the spatial domain analog radio signals or the spatial domain digital baseband signals. The method further comprises selectively processing the spatial domain analog radio signals or the spatial domain digital baseband signals depending on the determined signal strength level.

[00019] According to another aspect, a detection device configured for a receiver of a wireless communication network for handling wireless disturbance signals is disclosed. The receiver comprising radio antennas, and the device comprises an obtaining unit, configured to obtain antenna domain analog radio signals from the antennas. The device further comprises a passive hardware transforming unit configured to transform the obtained antenna domain analog radio signals from antenna domain into spatial domain and a down-conversion and analog-to-digital, ADC unit, configured to convert the spatial domain analog radio signals into spatial domain digital baseband signals. The device further comprises a determining unit, configured to determine a signal strength level of each of the spatial domain analog radio signals or the spatial domain digital baseband signals, and a selectively processing unit, configured to selectively process the spatial domain analog radio signals or the spatial domain digital baseband signals depending on the determined signal strength level.

[00020] According to another aspect, a network node is disclosed. The network node comprises the detection device described above.

[00021] According to another aspect, a UE is disclosed. The UE comprises the detection device described above.

[00022]According to other aspects, computer programs and carriers are also provided, the details of which will be described in the claims and the detailed description.

[00023] Further possible features and benefits of this solution will become apparent from the detailed description below.

Brief Description of Drawings

[00024] The solution will now be described in more detail by means of exemplary embodiments and with reference to the accompanying drawings, in which:

[00025] Fig. 1 is a schematic block diagram of a wireless communication network in which the embodiments of the present invention may be used.

[00026] Fig. 2 is a schematic block diagram of a jamming mitigation apparatus according to prior art.

[00027] Fig. 3 is a flow chart illustrating a method performed by a device of a receiver of a wireless communication network for handling disturbance wireless signals, according to some embodiments.

[00028] Fig. 4 is a flow chart illustrating a method performed by a device of a receiver of a wireless communication network for handling disturbance wireless signals, according to some embodiments

[00029] Fig. 5 is a schematic block diagram of a device of a receiver of a wireless communication network for handling disturbance wireless signals, according to some embodiments.

[00030] Fig. 6 is a schematic block diagram of a device of a receiver of a wireless communication network for handling disturbance wireless signals, according to some embodiments.

[00031] Fig. 7 is a schematic block diagram of a device for handling disturbance wireless signals in a UE, according to some embodiments.

[00032] Fig. 8 is a schematic block diagram of a device for handling disturbance wireless signals in a UE, according to some embodiments.

[00033] Fig. 9 is a schematic drawing of a 4x4 Butler Matrix, according to some embodiments

[00034] Fig. 10 is a schematic drawing of a Rotman lens, according to some embodiments. [00035] Fig. 11 is a flow chart illustrating a method performed by an apparatus in a UE, according to some embodiments.

[00036] Fig. 12 is a block diagram illustrating detection device, according to some embodiments.

Detailed Description

[00037] This invention can be utilized in the wireless communication network 100 shown in fig. 1. The wireless communication network 100 may be any kind of wireless communication network that can provide radio access to wireless communication devices. Example of such wireless communication networks are Global System for Mobile communication (GSM), Enhanced Data Rates for GSM Evolution (EDGE), Universal Mobile Telecommunications System (UMTS), Code Division Multiple Access 2000 (CDMA 2000), Long Term Evolution (LTE) Frequency Division Duplex (FDD) and Time Division Duplex (TDD), LTE Advanced, Wireless Local Area Networks (WLAN), Worldwide Interoperability for Microwave Access (WiMAX), WiMAX Advanced, as well as 5G wireless communication networks based on technology such as New Radio (NR), or even future wireless network such as 6G or higher version. However, the embodiments of the following detailed description are described for NR.

[00038] Further referring to fig. 1 , the network node 130 may be any kind of network node that provides wireless access to the number of UEs 140, 142 alone or in combination with another network node. The network node 130 may also be called radio network node in this disclosure. Examples of network node 130 are a base station (BS), a radio BS, a base transceiver station, a BS controller, a network controller, a Node B (NB), an evolved Node B (eNB), a gNodeB (gNB), a Multi-cell/multicast Coordination Entity, a relay node, an access point (AP), a radio AP, a remote radio unit (RRU), a remote radio head (RRH), nodes in a distributed antenna system (DAS) and a multi-standard radio BS (MSR BS).

[00039] The first and second UE 140, 142 may be any type of device capable of wirelessly communicating with a network node 130 using radio signals. The first and second user equipment may also be called wireless communication device, wireless device or simply device in this disclosure. For example, the first and second UE 140, 142 may be a machine type UE or a UE capable of machine to machine (M2M) communication, a sensor, a tablet, a mobile terminal, a smart phone, a laptop embedded equipped (LEE), a laptop mounted equipment (LME), a USB dongle, a Customer Premises Equipment (CPE) etc. The network node 130 and/or the UE 140, 142 may comprise at least one receiver configured to receive incoming signals.

[00040] Fig. 3, in conjunction with fig. 1 , fig. 4, fig. 5 and fig. 6, describes a method performed by a detection device 410 for a receiver of a wireless communication network 100, for handling disturbance wireless signals. For example, the receiver can be comprised in one or more of the network node 130, and UE 140, 142 described in conjunction with fig. 1. The detection device 410 is operably connected to a receiver circuit. By operably connected is meant that during operation of the detection device and receiver circuit a physical or wireless connection is present between the detection device and receiver circuit. Furthermore, the detection device can be connected to the receiver circuit, but can also be removed from the receiver circuit. The receiver comprises radio antennas. The method comprises obtaining 302 antenna domain analog radio signals from the antennas and transforming 304 the obtained 302 antenna domain analog radio signals from antenna domain into spatial domain using a passive hardware transforming unit 412. The method also comprises converting 306 the spatial domain analog radio signals into spatial domain digital baseband signals, determining 308 a signal strength level of each of the spatial domain analog radio signals or the spatial domain digital baseband signals and selectively processing 310 the spatial domain analog radio signals or the spatial domain digital baseband signals depending on the determined 308 interference or voltage level.

[00041] The sequence of the above steps are not definitive and can be altered according to different situation. This will be explained in detail in other embodiments.

[00042] The detection device 410 that performs this method can be an independent module, which can be directly plugged into the receiver to enhance the function of the receiver. The detection device 410 can also be integrated into the receiver when producing the receiver. The receiver can in some embodiments be comprised in the network node 130. The receiver can in some embodiments be comprised in the UE 140, 142. Thus a receiver comprised in either or both of the network node 130 and the UE 140, 142 can be enhanced by the detection device 410. The “disturbance wireless signals” can be any kind of wireless signals that cause disturbance which disturb the wireless communication, e.g, signals not intended to be received and processed by the receiver 130, 140, 142 but are received anyhow and thereby disturbs the actual signals that are intended to be received. The disturbance signals can be jamming, interference, high power signals, etc. These signals are typically not information signals and can bring negative effect to the wireless communication, e.g., disturbing communication, damage HW, etc.

[00043] In step 304, the obtained antenna domain signals are transformed to spatial domain, i.e., the obtained antenna domain signals are transformed into signals from different spatial directions at different spatial ports. This transformation is performed by a passive hardware transforming unit 412. The passive hardware transforming unit 412 may be comprised in the detection device 410. The passive hardware transforming unit 412 may be an independent passive hardware unit, which typically reduces the risk of damaging HW more than what e.g., an active electronic component would.

[00044] In step 308, the signal strength level of each of the spatial domain analog radio signals or the spatial domain digital baseband signals is determined. If the determining step 308 is performed to the spatial domain analog radio signals, the determining step 308 is performed before the converting step 306, as shown in fig. 4. If the determining step 308 is performed to the spatial domain digital baseband signal, the determining step 308 is performed after the converting step 306, as shown in fig. 3. This part will be explained in detail in following paragraphs. The signal strength level can be indicated by different indicators, e.g., voltage level, power level, etc.

[00045] In step 310, the spatial domain analog or digital signals with certain signal strength levels are selectively processed. For example, since the signal strength levels of the spatial domain analog or digital signals subjected to disturbance signals typically are high compared to undisturbed signals, they can be identified as being subjected to disturbance and further processed by handling the disturbance signals within the received wireless signals. The ports of spatial domain analog or digital signals subjected to disturbance signals can e.g., in some embodiments be blocked and the corresponding spatial domain analog or digital signals can be discarded and not passed to the LNA and baseband in order to protect sensitive components of the receiver from high signal strength levels that may be potentially damaging. In some embodiments, if the disturbance signals are not so high as to potentially damage HW, all the spatial analog or digital domain signals can be passed to baseband, but the signals with disturbance signals will not be used when processed in baseband. Step 310 can be performed to spatial domain analog radio signals, or spatial domain digital baseband signals. When the step 310 is performed to spatial domain analog radio signal, the step 310 is performed before the converting step 306, as shown in fig. 4. When the step 310 is performed to spatial domain digital baseband signal, the step 310 is performed after the converting step 306, as shown in fig. 3.

[00046] Referring to figs. 5 and 6, the detection device 410 is shown in detail. The detection device 410 comprises a passive hardware transforming unit 412, a down-conversion and ADC unit 424, a determining unit 420 and a selectively processing unit 418. The transforming step 304 is performed by the passive hardware transforming unit 412 and the converting step 306 is performed by the downconversion and ADC unit 424. The determining step 308 is performed by the determining unit 420 and the selectively processing step 310 is performed by the selectively processing unit 418. Furthermore, in some embodiments, antenna filters (not shown) can be present at antenna ports to suppress interference from other frequencies.

[00047] By such a method shown in fig. 3 or 4, the received wireless signals of the detection device 410 are transformed from antenna domain to spatial domain and the signals are associate with different spatial directions. The signal strengths of the spatial domain signals are determined and the spatial domain signals are selectively processed based on the signal strengths. Since the spatial domain signals with disturbance signals have higher signal strengths, these spatial domain signals with disturbance signals are detected and selectively processed.

[00048] According to some embodiments, the passive hardware transforming unit 412 is a Butler matrix or a Rotman lens. Further explanations of the Butler matrix and the Rotman lens can be found in figs. 9 and 10.

[00049] A Butler matrix or Rotman lens are existing passive hardware which are common in beamforming. However, instead of employing it to deliberately control the direction of a beam or beams, as applied conventionally in the context of regular antenna arrays for radio transmission, it may be used to generate multiple replicas with differing spatial or directivity characteristics from the received signals of antennas when the detection device 410 is implemented in a UE, not necessarily regularly or deterministically placed. When the detection device 410 is implemented in a network node, it may be used to perform a spatial decomposition of the received aggregate signal at the network node, detect and remove directions affected by jamming. When implemented in a network node the detection device 410 may in some embodiments return the rest of the signal to the original representation via an inverse transform. As noted above, a Butler matrix or Rotman lens is utilized as the passive hardware transforming unit 412 in this embodiment.

[00050] According to some embodiments, the method further comprises that the step of converting 306 the spatial domain analog radio signals into spatial domain digital baseband signals is performed by a plurality of parallel separate converting units, each converting unit converting 306 a subset of the spatial domain analog radio signals.

[00051] Since multiple converting units are utilized, the robustness of the detection device 410 is enhanced.

[00052] According to some embodiments, a subset of the spatial domain analog radio signals are converted to spatial domain digital baseband signals and used in subsequent baseband processing circuitry to obtain the digital information. The spatial domain analog radio signals which will not be converted are discarded before converting. By this method, only the spatial domain digital baseband signals which have high signal quality are used to obtain high quality digital information.

[00053] According to some embodiments, as shown in fig. 3, the method further comprises that the step of determining 308 a signal strength of each of the spatial domain analog radio signals or the spatial domain digital baseband signals is performed after the step of converting 306. Typically, when the converting step 306 is performed prior to the step of determining the signal strength, all of the spatial analog radio signals have been converted into spatial domain digital baseband signals and been passed into baseband. The signal strength is hence determined 308 only for each of the spatial domain digital baseband signals. The step of selectively processing 310 further comprises discarding the spatial domain digital baseband signals that were determined 308 to have a signal strength level above a digital baseband signal threshold.

[00054] As noted above, the determining 308 and the discarding are performed after converting the analog radio signals into digital baseband signals, so that the determining 308 and the discarding are performed in digital baseband. When the determined 308 signal strength of a spatial domain digital baseband signal is above a digital baseband signal threshold, the spatial domain digital baseband signal is determined to include a disturbance signal, and the spatial domain digital baseband signal may hence be discarded. In some embodiments, when a subset of the spatial domain analog radio signal has been converted into spatial domain digital base band signals, and the signal strength of one or more of the converted spatial domain digital baseband signals is determined to be above the digital baseband signal threshold, the step of selectively processing 310 may further comprise discarding the one or more digital baseband signals and discarding the remainder of the spatial domain analog radio signal associated with the one or more digital baseband signals.

[00055] In simple terms, if the detected signal strength, e.g., power level in one spatial port is determined to be above a defined threshold level, then that beam port is not used for reception. If a too high power is detected in one of the transform outputs, the respective port is immediately terminated in order to exclude the presumably jammed signal. [00056] Exclusion of selected transform output ports may be implemented using known techniques: disconnection, shorting, shunting, termination with an impedance not connected to active circuitry, etc. A good technique is to terminate the signal by using the characteristic impedance, i.e., switch in a component with the characteristic impedance between the signal and signal ground, most typically a resistor, often 50Q. The signal path is then disconnected after the termination, by a series switch that is opened, possibly followed by a closed shunt switch to signal ground for high isolation. In this way the output port signal is prevented from reaching the sensitive LNA and cause damage. At the same time the port is properly terminated and almost no signal is reflected, and the signal level at the termination can still be monitored by the power or voltage detector connected to the port, so that information about when/if the interference is gone can be obtained, and whether it is safe to switch in the output port again. Signals from the other beam ports are preferably not manipulated or affected.

[00057] Referring to fig. 5, the determining unit 420 and the selectively processing unit 418 are connected to the output of the down-conversion and ADC unit 424. The digital baseband signal threshold can be set based on typical received power levels, linear region of the LNA and/or ADC, or other BS implementation-related criteria. The threshold may be e.g., based on an average or maximum signal level estimated or observed for non-disturbance signal scenarios in previous operation. Still, a more elaborate application would involve monitoring the beam ports over a time window to identify sudden increases in beam signal strength in a given scenario.

[00058] According to some embodiments, as shown in fig. 4, the method further comprises that the step of determining 308 a signal strength level of each of the spatial domain analog radio signals or the spatial domain digital baseband signals are performed before the step of converting 306. Hence, the spatial domain analog radio signals have not been converted into spatial domain digital baseband signals and not yet passed on to baseband. The signal strength level is hence determined 308 only for each of the spatial domain analog radio signals. The step of selectively processing 310 further comprises: discarding the spatial domain analog radio signals that were determined 308 to have a signal strength level above an analog radio signal threshold.

[00059] As noted above, the determining 308 and the discarding are performed before converting the analog radio signals into digital baseband signals, so that the determining 308 and the discarding are performed in the analog radio band. When the determined 308 signal strength of a spatial domain analog radio signal is above an analog radio signal threshold, the spatial domain analog radio signal is determined to include a disturbance signal, and the spatial domain analog radio signal will be discarded and hence not passed on to baseband.

[00060] In simple terms, if the detected signal strength, e.g., power level in one spatial port is determined above a defined threshold level, then that beam port is not used for reception. If a too high power is detected in one of the transform outputs, the respective port is immediately terminated in order to exclude the presumably jammed signal.

[00061] Exclusion of selected transform output ports may be implemented using known techniques: disconnection, shorting, shunting, termination with an impedance not connected to active circuitry, etc. A good technique is to terminate the signal by using the characteristic impedance, i.e., switch in a component with the characteristic impedance between the signal and signal ground, most typically a resistor, often 500. The signal path is then disconnected after the termination, by a series switch that is opened, possibly followed by a closed shunt switch to signal ground for high isolation. In this way the output port signal is prevented from reaching the sensitive LNA and cause damage. At the same time the port is properly terminated and almost no signal is reflected, and the signal level at the termination can still be monitored by the power or voltage detector, so that information about when/if the interference is gone can be obtained, and whether it is safe to switch in the output port again. Signals from the other beam ports are preferably not manipulated or affected.

[00062] Referring to fig. 6, the determining unit 420 and the selectively processing unit 418 are connected to the input of the down-conversion and ADC unit 424. The analog radio signal threshold can be set based on typical received power levels, linear region of the LNA and/or ADC, or other BS implementation-related criteria. The threshold may be e.g., based on average or maximum signal level estimated or observed for non-disturbance signal scenarios in previous operation. Still, a more elaborate application would involve monitoring the beam ports over a time window to identify sudden increases in beam signal strength in a given scenario.

[00063] According to some embodiments, in conjunction with fig. 6, prior to the step of discarding, the step of selectively processing 310 further comprises: providing the determined 308 signal strength to a baseband processing unit 426 of the receiver, wherein the baseband processing unit 426 processes the signals outputted by the device 410. The method further comprises receiving from the baseband processing unit 426, a control command to discard the spatial domain analog radio signals that were determined 308 to have a signal strength above the analog radio signal threshold, and the step of discarding of the spatial domain analog radio signals that were determined 308 to have a signal strength level above the analog radio signal threshold is performed in response to the received control command.

[00064] In this embodiment, the baseband processing unit 426 is connected to the selectively processing unit 418, and a control command is sent from the baseband processing unit 426 to the selectively processing unit 418, to inform the selectively processing unit 418 to discard the signals which are determined to have a signal strength above the analog radio signal threshold.

[00065] According to some embodiments, the method further comprises receiving a control instruction from the baseband processing unit 426 of the receiver. The baseband processing unit 426 processes the signals outputted by the detection device 410. The control instruction includes information on the analog radio signal threshold level. The method comprises configuring the analog radio signal threshold based on the received control instruction.

[00066] According to some embodiments, the step of determining 308 a signal strength level of each of the spatial domain analog radio signals or the spatial domain digital baseband signals is performed over time. When the determined 308 signal strength level increases over time, the method may comprise triggering transmission to a transmitter, which transmitter is using a current modulation and coding scheme, MCS, for transmitting radio signals for reception by the receiver, to utilize a MCS that is more robust than the current MCS for a subsequent transmission of radio signals for reception by the receiver.

[00067] During a regular uplink (UL) communication between the UE and the BS, the MCS will be determined based on UE sounding. E.g., sounding reference signal (SRS) transmission in the UL is used to estimate the total link signal-to-noise ratio (SNR). The higher the link SNR, the higher modulation scheme may be used and the better resource utilization and higher throughput can be achieved. Generally, for normal communication there will be some margin related to an allowed first transmission block error rate -- for regular communication, the target block error rate (BLER) could be set quite high and a relatively small SINR margin could be used to optimize overall system capacity since e.g., several re-transmissions could be allowed with no significant performance impact. By utilizing re-transmissions for non-latency critical applications, effective resource utilization per transmission can be kept low.

[00068] By this method, when the disturbance signals in the wireless signals are determined to increase over time, a more robust MCS may be utilized by a transmitter to eliminate the effects of the disturbance signals.

[00069] According to some embodiments, the method further comprises determining signal quality of each of the spatial domain analog radio signals or the spatial domain digital baseband signals overtime and determining an MCS to be used by a transmitter transmitting signals to the receiver based on the determined signal quality of a subset of the spatial domain analog radio signals or spatial domain digital baseband signals. The subset may exclude one or more of the spatial domain analog radio signals or spatial domain digital baseband signals. Furthermore, the subset may be selected based on the determined signal quality over time that has the highest quality. The method may further comprise triggering transmission, to the transmitter, of the determined MCS. An indication of the determined MCS can be transmitted to the transmitter. The indications indicating to the transmitter which MCS to apply.

[00070] According to some embodiments, the subset excluding one or more of the spatial domain analog radio signals or spatial domain digital baseband signals further comprises excluding one or more of the spatial domain analog signals or spatial domain digital baseband signals that have been determined to have worse signal quality than the remaining spatial domain analog radio signals or spatial domain digital baseband signals, and/or excluding one or more spatial domain analog signals or spatial domain digital baseband signals that have been determined to have better signal quality than the remaining spatial domain analog radio signals or spatial domain digital baseband signals.

[00071] By this method, the spatial domain signals with worst signal quality and/or the spatial signals with highest quality are excluded from the MCS determination. The signal qualities can be indicated by SNR, SINR, BER, BLER, etc. Hence the determination of MCS gain more robustness. For example, the spatial domain signals that over time has been determined most vulnerable to disturbance/interference or where jamming is most likely to occur are excluded. This is an approach based on historical data or some a priori knowledge about jamming characteristics. For another example, the spatial domain signals with best signal qualities are excluded. These spatial domain signals correspond the spatial directions which would have largest impact if being jammed. This is a worst-case approach. One key of this embodiment is setting a more robust MCS by excluding a subset of spatial domain signals when determining the MCS. The excluded spatial domain signals corresponding to the spatial directions where interference/disturbance would likely to occur or the spatial directions that contribute most to total signal. These two types of excluded spatial domain signals can also have weight and being combined in this embodiment.

[00072] For example, for communication services that have a latency and reliability bound (like ultrareliable low latency communication URLLC), a stricter guarantee of the margins would typically be needed. During normal communication without disturbance signals, the UE transmits UL sounding signals and the BS estimates the total link SNR (SNRTOT) when utilizing beam ports. However, the BS may also estimate the SNR when not using all available spatial ports, e.g., if current best beam port (SNR-BEST BP), the second-best beam port (SNR-2nd BEST Bp), or the best and second-best beam ports (SNR BEST & 2nd BEST BP) are removed. It is clear that the difference between SNRTOT and SNR-BEST BP will be large if only one dominating line of sight (LOS) channel is present and hence the system will be very sensitive to a jammer/interference in the LOS direction, while the system will have redundancy in a spatially rich environment. The BS can adapt the MCS allocation and the decoding margin based on the estimated sensitivity - a larger margin may be used if the performance loss due to losing the best beam port is large.

[00073] Depending on the required reliability, the BS can e.g., use not the full SNRTOT but one of the SNR metrics corresponding to one or more best beam ports being unavailable. The SNR metrics are listed as simple UL channel state information (CSI) examples. Full CSI estimation includes additionally or alternatively preferred rank, preferred precoding, and available mutual information metrics; these metrics may be modified to obtain a larger decoding margin.

[00074] By this method, a part of the spatial domain analog radio signals or spatial domain digital baseband signals are used to determine the MCS. The spatial domain analog radio signals or spatial domain digital baseband signals which are excluded can be the signals with highest quality or based on historical spatial interference.

[00075] According to some embodiments, the receiver is arranged in a network node, and the method further comprises transforming either the selectively processed 310 spatial domain analog radio signals into antenna domain or the selectively processed spatial domain digital baseband signals into antenna domain.

[00076] Hence, in some embodiments, the selectively processed spatial domain signals are transformed back into antenna domain. This transformation can be performed to analog radio signals or digital baseband signals. In the embodiment shown in fig. 6, the transformation is performed by an inverse transform unit 422 and the analog spatial domain signals are transformed back to analog antenna domain signals. In other words, spatial domain signals which are not affected by disturbance signals are fed into an inverse transform unit 422 and transformed back to its original antenna domain signals.

[00077] Referring to fig. 6, the inverse transform unit 422 is preferably implemented using passive circuitry similar to the transform unit 412. In one embodiment, the same hardware design is used but the unit 422 is connected in the reverse order, i.e. output port connections of the transform unit 412 become input ports for the inverse transform unit 422. This ensures near-unity aggregate response due to the inversion property of a full-rank linear transform through passive hardware.

[00078] Alternatively, the inverse transformation can also be performed in baseband, where the inverse transformation is performed to digital baseband signals. Performing it in baseband will reduce both size and cost and will typically also minimize losses.

[00079] Fig. 5 and Fig. 6 are schematic block diagrams of a detection device 410 for a receiver of a wireless communication network for handling disturbance wireless signals. The detection device 410 is configured for a receiver of a wireless communication network 100 and is used for handling wireless disturbance signals. The receiver comprises radio antennas. The detection device 410 comprises an obtaining unit, configured to obtain antenna domain analog radio signals from the antennas. The detection device 410 comprises a passive hardware transforming unit 412 configured to transform the obtained antenna domain analog radio signals from antenna domain into spatial domain. The detection device 410 further comprises a down-conversion and analog-to-digital, ADC unit 424 configured to convert the spatial domain analog radio signals into spatial domain digital baseband signals. The detection device 410 comprises a determining unit 420 configured to determine a signal strength level of each of the spatial domain analog radio signals or the spatial domain digital baseband signals. The detection device 410 further comprises a selectively processing unit 418, configured to selectively process the spatial domain analog radio signals or the spatial domain digital baseband signals depending on the determined signal strength level.

[00080] In this application, the term “receiver” is used as a general name of network part that receives signal, and can typically be comprised in a UE or a network node.

[00081] According to some embodiments, the passive hardware transforming unit 412 is a Butler matrix or a Rotman lens.

[00082] According to some embodiments, the down-conversion and ADC unit 424 comprises a plurality of parallel separate converting units, each converting unit converting a subset of the spatial domain analog radio signals.

[00083] According to some embodiments, the determining unit 420 is connected after the downconversion and ADC unit 424. However, the actual placement of the components on the circuit board may vary and may change depending on e.g. size of the components and the circuit board.

Furthermore, the detection device 410 may comprise controlling circuitry (not shown) which e.g. causes the described components and units to carry out method steps described herein in a certain order (regardless of their placement on the circuit board). In some embodiments the determining unit 420 is configured to determine signal strength level only for each of the spatial domain digital baseband signals. The selectively processing unit 418 is further configured to discard the spatial domain digital baseband signals that were determined to have a signal strength level above a digital baseband signal threshold (as shown in fig. 5).

[00084] According to some embodiments, the determining unit 420 is connected before the downconversion and ADC unit 424. However, the actual placement of the components on the circuit board may vary and may change depending on e.g. size of the components and the circuit board.

Furthermore, the detection device 410 may comprise controlling circuitry (not shown) which e.g. causes the described components and units to carry out method steps described herein in a certain order (regardless of their placement on the circuit board). In some embodiments the determining unit 420 is configured to determine signal strength level only for each of the spatial domain analog radio signals. The selectively processing unit 418 is further configured to discard the spatial domain analog radio signals that were determined to have a signal strength level above an analog radio signal threshold (as shown in fig. 6).

[00085] According to some embodiments, the selectively processing unit 418 is further configured to provide the determined signal strength level to a baseband processing unit 426 of the receiver. The baseband processing unit 426 processes the signals outputted by the detection device 410. The selectively processing unit 418 is further configured to receive, from the baseband processing unit 426, a control command to discard the spatial domain analog radio signals that were determined to have a signal strength level above the analog radio signal threshold. The selectivity processing unit 418 is configured to discard of the spatial domain analog radio signals that were determined to have a signal strength level above the analog radio signal threshold in response to the received control command.

[00086] According to some embodiments, the selectively processing unit 418 is further configured to receive a control instruction from the baseband processing unit 426 of the receiver. The baseband processing unit 426 processes the signals outputted by the detection device 410. The control instruction includes information on the analog radio signal threshold level. The selectively processing unt 418 is further configured to configure the analog radio signal threshold based on the received control instruction.

[00087] According to some embodiments, the determining unit 420 is further configured to determine a signal strength level of each of the spatial domain analog radio signals or the spatial domain digital baseband signals over time. The receiver further comprises a transmitting unit configured to trigger transmission to a transmitter that uses a current modulation and coding scheme, MCS, for transmitting radio signals for reception by the receiver, of an instruction to utilize an MCS that is more robust than the current MCS for a subsequent transmission of radio signals for reception by the receiver, when the determined signal strength level increases over time.

[00088] According to some embodiments, the determining unit 420 is further configured to determine signal quality of each of the spatial domain analog radio signals or the spatial domain digital baseband signals over time. The determining unit 420 is further configured to determine an MCS to be used by a transmitter, that transmits signals to the receiver, based on the determined signal quality of a subset of the spatial domain analog radio signals or spatial domain digital baseband signals. The subset excludes one or more of the spatial domain analog radio signals or spatial domain digital baseband signals. The subset is selected based on the determined signal quality over time. The receiver further comprises a transmitting unit configured to trigger transmission to the transmitter of an indication of the determined MCS.

[00089] According to some embodiments the subset excluding one or more of the spatial domain analog radio signals or spatial domain digital baseband signals may further exclude one or more of the spatial domain analog signals or spatial domain digital baseband signals that have been determined to have worse signal quality than the remaining spatial domain analog radio signals or spatial domain digital baseband signals, and/or excludes one or more spatial domain analog signals or spatial domain digital baseband signals that have been determined to have better signal quality than the remaining spatial domain analog radio signals or spatial domain digital baseband signals.

[00090] According to some embodiments, the receiver is arranged in a network node 130, and the detection device 410 further comprises an inverse transform unit 422. The inverse transform unit 422 is configured to transform either the selectively processed spatial domain analog radio signals into antenna domain or the selectively processed spatial domain digital baseband signals into antenna domain.

[00091] Fig. 7 and fig. 8 are schematic block diagrams of the detection device 410 for handling disturbance wireless signals in a UE. A UE receives wireless signals from multiple antennas. In some embodiments, the received wireless signals are fed into a Butler Matrix. The Butler Matrix is used as the transform unit 412 and transforms the antenna domain analog radio signals to spatial domain analog radio signals. Referring to fig. 8, the spatial domain analog radio signals are inputted into an Overvoltage Detection & Protection & Switch. The Overvoltage Detection & Protection & Switch works as the determining unit 420 and the selectively processing unit 418 previously described. The overvoltage spatial domain analog radio signals are detected and processed. In some embodiments, the ports of the overvoltage signals are turned off and the overvoltage signals are discarded to avoid any damaging of the hardware. The output of the Overvoltage Detection & Protection & Switch is connected to the input of multiple transceiver circuits, then connected to the baseband circuit. In some embodiments, e.g., as described in conjunction within fig. 7, due to the limited space of the UE, if the disturbance signals are expected not to be strong, the Overvoltage Detection & Protection & Switch may be omitted, and the spatial domain analog radio signals are fed directly to multiple transceiver circuits (TRX OCT) and baseband circuit (baseband OCT). The disturbance signals can be handled further in the baseband circuit.

[00092] As noted above, a Butler matrix or Rotman lens can be used as the passive hardware transforming unit 412. A Butler matrix is a beamforming network traditionally used to feed a phased array of antenna elements. Its purpose is to control the direction of a beam, or beams, of radio transmission. It typically consists of a nxn matrix of hybrid couplers and fixed-value phase shifters where n is some power of 2. A common set of phase shifter values corresponds to DFT coefficients. The device has n input ports, e.g., the beam ports, to which power is applied, and n output ports e.g., the element ports, to which n antenna elements are connected. The Butler matrix feeds power to the elements with a progressive phase difference between elements such that the beam of radio transmission is in the desired direction. The beam direction is controlled by switching power to the desired beam port. More than one beam, or even all n of them can be activated simultaneously. For reception, the reverse processing is applied, i.e., the beam ports are used as outputs.

[00093] Its advantage over other methods of angular beamforming is the simplicity of the hardware. It requires fewer phase shifters than other methods, and the phase shifters can have fixed phase shifts rather than variable. Furthermore, the entire structure can be implemented in microstrip on a low-cost printed circuit board. Fig. 9 shows a 4x4 version of the Butler matrix 900 apply DFT coefficients and comprising four couplers 901 a-d and two phase shifters 902a-b. This is just an example and other designs of a butler matrix are feasible. E.g. a Butler matrix can also have 8x8 or other dimension versions.

[00094] The transform of Butler matrix can also be 2-D, providing beam-domain signal representation in in 2 dimensions (azimuth and elevation), respectively.

[00095] Fig. 10 shows a schematic representation of an example Rotman lens 700, which can be used in the detection device 410, according to possible embodiments. It should be noted that the rotman lens illustrated by figure 10 is just an example and other designs of the lens are feasible. A Rotman lens is another classic microwave technique for passive beamforming networks. Despite the name it is not a lens. It is realized as a planar metal structure 701 e.g., on a printed circuit board. It allows multiple antenna beams to be formed without the need for switches or phase shifters. Antenna elements 704a-f are connected to the right side of the figure, with beam ports 702a-e connected to the left. The lens acts as a quasi-microstrip (or quasi-strip line) circuit where the beam ports are positioned such that constant phase shifts are achieved at the antenna ports. When antenna elements are fed at phases that vary linearly across a row, the elements behave just like a phased array. Furthermore, dummy ports 703a-n may be positioned between the beam ports 702a-eand antenna ports/elements 704a-f in order to reduce mutual coupling between ports. One noteworthy property of this lens is that even though there may be many 50 ohm ports, they are isolated, in that they don't affect the loss (or noise figure) of adjacent beams. A well-designed lens may have just 1 dB of loss.

[00096] Fig. 11 shows a flow chart illustrating a method performed by a detection device in a UE, e.g., the detection device described previously in conjunction with Figs 7 and 8, according to some embodiments.

[00097] Different butler matrix ports will output signals corresponding to received signal components arriving from different spatial directions in step 510. If it is determined in step 512 that no Overvoltage Detection & Protection & Switch (OV-D-P & switch) is included in the detection device, all the signals are passed to the multiple TRX circuits and later to the baseband circuit in step 514. If it is determined in step 516 that the baseband can decode the combined signal with a good SNR, then no disturbance signals, e.g., interference/jamming is assumed. If the baseband circuit, upon combining all signals from all antennas cannot decode the signal, or can be decoded with very poor SNR, then interference/jamming is assumed, and the baseband circuit acts to identify the jamming signal indices in step 518. Once identified, the strong signals with poor SNR are excluded from any further baseband processing and the base station is informed about the jammed signal indices in step 520.

[00098] Now if an OV-D-P & switch is included in the device, then any signals that are above a certain voltage threshold are blocked in step 522. All the undervoltage signals are passed to the multiple TRX circuits and later to the baseband circuit in step 524. If the baseband circuit can decode the combined signal with a good SNR in step 526, then all jamming signals have already been excluded by the OV-P-D & switch circuit and the antennas of the UE can continue to receive replicas of a waveform in step 510. If the baseband circuit, upon combining signals from antennas, cannot decode the signal, or can be decoded with very poor SNR in step 526, then interference/jamming is assumed, and the baseband circuit acts to identify the jamming signal indices in step 518. Once the interfering signal is identified in step 518, the jammed signals are excluded from any further baseband processing and the base station is informed about the jammed signal indices in step 520. Moreover, the baseband circuit could also in some embodiments inform the OV-P-D & switch of the interfering signal indices for possible future exclusions.

[00099] Referring to fig. 12, a detection device 410 according to some embodiments is shown. The detection device 410 may e.g., be the same detection device 410 described in conjunction with any of the Figs. 5-8. The detection device 410 comprises a data-processing unit 601 . The data-processing unit 601 comprises a processing circuitry 603, a memory 604 and a computer program 605 that has been stored into the memory 604. The processing circuit 603 and the memory 604 are associated or integral to the data-processing unit 601 . The computer program 605 is configured to be loadable into the data- processing unit 601 . The computer program 605 may be arranged such that when its instructions are run in the processing circuitry 603, they cause the detection device 410 to perform the steps described in any of the described embodiments of the methods of the detection device 410. The computer program 605 may be carried by a computer program product connectable to the processing circuitry 603. The computer program product may be the memory 604, or at least arranged in the memory. The memory 604 may be realized as for example a RAM (Random-access memory), ROM (Read-Only Memory) or an EEPROM (Electrical Erasable Programmable ROM). In some embodiments, a carrier may contain the computer program 605. The carrier may be one of an electronic signal, an optical signal, an electromagnetic signal, a magnetic signal, an electric signal, a radio signal, a microwave signal, or computer readable storage medium. The computer-readable storage medium may be e.g. a CD, DVD or flash memory, from which the program could be downloaded into the memory 604. Alternatively, the computer program may be stored on a server or any other entity to which the detection device 410 has access via the communication unit 602. The computer program 605 may then be downloaded from the server into the memory 604.

[000100] The described embodiments and their equivalents may be realized in software or hardware or a combination thereof. They may be performed by general-purpose circuits associated with or integral to a communication device, such as digital signal processors (DSP), central processing units (CPU), co- processor units, field-programmable gate arrays (FPGA) or other programmable hardware, or by specialized circuits such as for example application-specific integrated circuits (ASIC). All such forms are contemplated to be within the scope of this disclosure.

[000101] Embodiments may appear within an electronic apparatus (such as a wireless communication device) comprising circuitry/logic or performing methods according to any of the embodiments. The electronic apparatus may, for example, be a portable or handheld mobile radio communication equipment, a mobile radio terminal, a mobile telephone, a base station, a base station controller, a pager, a communicator, an electronic organizer, a smartphone, a computer, a notebook, a USB-stick, a plug-in card, an embedded drive, or a mobile gaming device.

[000102] According to some embodiments, a computer program product comprises a computer readable medium such as, for example, a diskette or a CD-ROM. The computer readable medium may have stored thereon a computer program comprising program instructions. The computer program may be loadable into a data-processing unit, which may, for example, be comprised in a mobile terminal. When loaded into the data-processing unit, the computer program may be stored in a memory associated with or integral to the data-processing unit. According to some embodiments, the computer program may, when loaded into and run by the data-processing unit, cause the data-processing unit to execute method steps according to, for example, the methods shown in any of the Figures 3, 4 and 11 .

[000103] Although the description above contains a plurality of specificities, these should not be construed as limiting the scope of the concept described herein but as merely providing illustrations of some exemplifying embodiments of the described concept. It will be appreciated that the scope of the presently described concept fully encompasses other embodiments which may become obvious to those skilled in the art, and that the scope of the presently described concept is accordingly not to be limited. Reference to an element in the singular is not intended to mean "one and only one" unless explicitly so stated, but rather "one or more." Further, the term “a number of’, such as in “a number of wireless devices” signifies one or more devices. All structural and functional equivalents to the elements of the above-described embodiments that are known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed hereby. Moreover, it is not necessary for an apparatus or method to address each and every problem sought to be solved by the presently described concept, for it to be encompassed hereby. In the exemplary figures, a broken line generally signifies that the feature within the broken line is optional.