TECHNICAL FIELD

Embodiments herein relate to a communication node and a method therein. In particular, embodiments herein relate to managing interference between multiple transceivers.

BACKGROUND

In current wireless communication systems, it is becoming increasingly more common to have objects with multiple transceivers. This is due to the increasing demand by users for the simultaneous availability of a variety of wireless communication services, such as cellular services, e.g., LTE, HSPA, local services, e.g., WiFi, ad-hoc services, e.g., Bluetooth, and positioning services, e.g., GPS.

In these objects, it is also often the case that the transceivers share a common antenna system.

One example of such an object is a vehicle that has multiple cellular transceivers built-in, which are connected to a common antenna system. In the future, most vehicles may have strong shielding due to thermal isolation. The vehicle interior may then become a coverage hole from the cellular perspective. While the antenna system may typically be located on the outside of the vehicle, and therefore not shielded, wireless devices within the vehicle such as user equipment's, cell phones or tablets may not be able to transmit and receive directly to and from the cellular infrastructure due to the shielding. Wireless devices within the vehicle may be able to connect to the transceivers via some short- range communication, e.g. Bluetooth, WiFi, to configure those transceivers as, remote wireless devices with their communication credentials, e.g., remote SIM profile in

Bluetooth, or an equivalent WiFi solution.

Another example of such an object with multiple transceivers sharing a common antenna system is a device that has multiple transceivers which can connect

simultaneously to multiple networks, e.g., of different operators. This should provide communication redundancy and failover protection. A use case could be for critical control or measurements devices, e.g., which are monitoring a power grid operation or other control process, e.g., in industrial automation or critical infrastructure protection. When multiple transceivers use the same antenna system simultaneously, such as in the examples just provided, there may be some coupling interference among the reception/transmission signals due to the physical proximity of the transceivers and the connection to a common antenna system. The interference is primarily caused by the transmitted signal of one transceiver coupling into the receiving part of another transceiver.

SUMMARY

It is therefore an object of embodiments herein to provide a way of improving the performance of communications in a communication node that has multiple transceivers which share a common antenna system.

According to a first aspect of embodiments herein, the object is achieved by a method in a communication node, for managing interference between a first transceiver and at least a second transceiver. The communication node comprises at least the first transceiver and the second transceiver. The first and second transceivers are arranged to be connected to an antenna set comprising at least two antennas. The communication node determines an interference between a signal associated with the first transceiver and at least a signal associated with the second transceiver. When the interference exceeds a threshold, the communication node configures a first connection between a transmitting part of the first transceiver and one or more first antennas of the antenna set, and configures a second connection between a receiving part of the second transceiver and one or more second antennas of the antenna set. At least one antenna is different between the one or more first antennas and the one or more second antennas.

According to a second aspect of embodiments herein, the object is achieved by a communication node, for managing interference between a first transceiver and at least a second transceiver. The communication node comprises at least the first transceiver and the second transceiver. The first and second transceivers are arranged to be connected to an antenna set comprising at least two antennas. The communication node comprises: a processing circuit. The processing circuit is configured to determine an interference between a signal associated with the first transceiver and at least a signal associated with the second transceiver. The processing circuit is also configured to, when the

interference exceeds a threshold, configure a first connection between a transmitting part of the first transceiver and one or more first antennas of the antenna set, and configure a second connection between a receiving part of the second transceiver and one or more second antennas of the antenna set. At !east one antenna is different between the one or more first antennas and the one or more second antennas.

An advantage of embodiments herein is that by connecting different transceivers to different antennas, at !east partly, the coupling interference is avoided or at !east reduced. This results in that the performance of communications in the communication node is improved.

A further advantage according to embodiments herein is that the transmission performance can be improved due to the reduced coupling interference.

A yet further advantage according to embodiments herein is that the number of antenna systems can be reduced since a common antenna system can be used for multiple transceivers.

BRIEF DESCRIPTION OF THE DRAWI GS

Examples of embodiments herein are described in more detail with reference to attached drawings in which:

Figure 1 is a schematic block diagram illustrating embodiments in a communication node that has multiple transceivers which share a common antenna system.

Figure 2 is a flowchart depicting embodiments of a method in a communication node. Figure 3 is a schematic block diagram illustrating embodiments of a communication

node.

DETAILED DESCRIPTION

Figure 1 depicts a communication node 100 in which embodiments herein may be implemented. The communication node 100 is a wireless communication node such as a communication node embedded within a vehicle or a control unit.

The communication node 100 has more than one transceiver. For the sake of simplicity, in the embodiment shown in Figure 1 , the communication node 100 comprises a first transceiver 111 and a second transceiver 112. The accompanying description is based on embodiments wherein the communication node 100 has two transceivers.

However, in other embodiments, the communication node 100 may have more than two transceivers. The embodiments herein described also apply to communication nodes with more than two transceivers, as one of skill in the art will appreciate. in some embodiments, each of the first transceiver 11 1 and second transceiver 1 12 may contain at ieast a transmitter, or transmitting part, and a receiver, or receiving part. In other embodiments, each of the first transceiver 11 1 and second transceiver 1 12 may contain oniy a transmitting part or only a receiving part. The first transceiver 1 1 and second transceiver 1 12 may be a e.g. one of a GSM, WCDMA, LTE, WiMAX, CDMA2000, WLAN, DVB, or DAB transceiver.

The first transceiver 11 1 and the second transceiver 122 share a common antenna system 120. The antenna system 120 comprises two or more antennas, that may be arranged to be connected to at Ieast one of a plurality of transceivers. In the embodiment shown in Figure 1 , the antenna system 120 has n antennas.

The antennas in the antenna system 120 may be of any antenna type known in the art. Each of the antennas in antenna system 120 enables transmission or reception of radio signals to or from further network nodes, i.e., other network nodes, where the networks nodes may be base stations in a cellular communication network, e.g., GSM, WCDMA, LTE, WiMAX, CDMA2000, access points or stations in a wireless local area network, e.g., WiFi, DSRC, 802.15, or broadcast stations, e.g., DAB, DVB. In the embodiment depicted in Figure 1 , the first transceiver 1 1 1 is arranged to be connected to a first network node 131 through one or more of the 1 to n antennas in the antenna set 120, via one or more of 1 to n links 141. Each of the 1 to n links 141 may communicate each of the 1 to n antennas, respectively, with the network node 131 , as shown in Figure 1. The communication path from the first transceiver 1 1 1 to the first network node 131 is depicted in Figure 2 with solid lines. In the embodiment depicted in Figure 1 , the second transceiver 112 is arranged to be connected to a second network node 132 through one or more of the 1 to n antennas in the antenna set 120, via one or more of 1 to n finks 142. Each of the 1 to n links 142 may communicate each of the 1 to n antennas, respectively, with the network node 132, as shown in Figure 1. The communication path from the second transceiver 1 12 to the second network node 132 is depicted in Figure 2 with thick hatched lines. In communication node 100, each of the transmitting and receiving parts of the first transceiver 1 1 1 and the second transceiver 112 may be configured to be connected to one or more antennas of the antenna set 120. Thus, the transmitting part of the first transceiver 111 may be configured to be connected to one or more first antennas, the receiving part of the second transceiver 1 12 may be configured to be connected to one or more second antennas, the transmitting part of the second transceiver 1 12 may be configured to be connected to one or more third antennas, and the receiving part of the first transceiver 1 1 1 may be configured to be connected to one or more fourth antennas. In some embodiments, each of these one or more first, second, third and fourth antennas may be the same, whereas in other embodiments, each or some these one or more first, second, third and fourth antennas may be different, as will be described below.

In some embodiments, there may be a coupling gain 150 between each pair of antennas in the antenna set 120, e.g., A1 A2, A1 OA3, etc . , as depicted in Figure 1.

In some particular embodiments, the antenna system 120 may be arranged to be connected to the first transceiver 11 and the second transceiver 1 12 through a

switching system 160, as depicted in the embodiment shown in Figure 1.

in these embodiments, the switching system 160 enables the transceivers to be connected to the different antennas. The switching system 160 may be a system that enables selectively connecting antennas to the transmitters and/or receivers of the at least one of a multitude of transceivers, such as first transceiver 11 and the second transceiver 1 12.

In some embodiments, the first transceiver 1 11 may be arranged to be connected with a first wireless device 171 while the second transceiver 1 12 may be arranged to be connected with a second wireless device 172. The first wireless device 71 and the second wireless device 172 may, for example, be mobile terminals or wireless terminals, mobile phones, computers such as, e.g., a laptop, Personal Digital Assistant, PDA, or tablet computers, sometimes referred to as surf plates, with wireless capability, devices equipped with a wireless interface, such as a printer or a file storage device or any other radio network unit capable of communicating over a radio or wired link in a cellular communications system.

The first transceiver 1 1 1 may be arranged to be connected with the first wireless device 171 through a first link 181 , while the second transceiver 112 may be arranged to be connected with the second wireless device 172 through a second link 182. The first and second links, 151 and 152, respectively, may be, e.g., established via some short range radio technology, such as Bluetooth or WiFi or via some fixed technology communicating via a cable.

In some embodiments, not depicted in Figure 1 , the first transceiver 1 1 1 may be associated with a first Subscriber Identity Module, SIM, and the second transceiver 112 may be associated with a second SIM, neither of which is depicted in Figure 1. Each of the SIMs may be a either a SIM card or a software SIM, and it may comprise at least the subscription credentials that enable communication with a cellular network. Each of the S!Ms may allow the respective transceiver to communicate with the cellular network nodes and the radio technologies and frequency carriers that are authorized by the subscription.

In some of these embodiments, at least one of the first transceiver 1 and the second transceiver 112 may be associated with the first SIM, and second SIM, respectively, by a remote-SIM-access connectivity that is established via a wireless technology. This may happen for example when wireless devices within a vehicle having multiple transceivers can connect to the transceivers via some short-range

communication technology, e.g., Bluetooth or WiFi, to configure those transceivers as remote wireless devices with their communication credentials, e.g., remote SIM profile in Bluetooth, or an equivalent WiFi solution.

In some other of these embodiments, at least one of the first transceiver 11 1 and the second transceiver 112 may be associated with the first SIM, and second SIM, respectively, by a physical connection of a SIM to the at least one of first transceiver 1 1 1 and the second transceiver 12. This may happen for example when a hardware SIM is connected to the transceiver via a connector.

In yet some other of these embodiments, at least one of the first transceiver 1 11 and the second transceiver 12 may be associated with the first SIM, and second SIM, respectively, by a dynamic re-configuration of a software-based SIM, that is embedded in at least one of the first transceiver 11 1 and the second transceiver 1 12 and is

reprogrammed with SIM credentials according to a software-based configuration procedure. The reprogramming can be achieved by any of the credential provisioning schemes known in the art, such, e.g., those defined by 3GPP or GSMA.

in the embodiments in which the communication node 100 has more than two transceivers, each of the additional transceivers may be associated with its own SIM.

In some particular embodiments, the communication node 100 may be located in a vehicle, such as a car, and the antenna set may be located on the outside of the vehicle.

Embodiments of a method in a communication node 00, for managing interference between a first transceiver 1 1 1 and at least a second transceiver 1 12 will now be described with reference to the flowchart depicted in Figure 2. In some of these embodiments, managing the interference may mean to reduce an existing or a predicted interference, while in other embodiments, managing the interference may mean to avoid an existing or predicted interference altogether, as described below. As mentioned above, the communication node 100 comprises at least the first transceiver 1 1 1 and the second transceiver 1 12, wherein the first and second transceivers 1 1 1 , 1 12 are arranged to be connected to the antenna set 120 comprising at least two antennas.

It is to be noted that some of the described actions are optional and only comprised within some embodiments. In Figure 2, optional actions are depicted in hatched line boxes, whereas non-optionai actions are depicted in solid line boxes. Further, it is to be noted that the following actions may as be carried out in another suitable order than described below.

Action 201

When multiple transceivers are located within the same object and with a certain physica! proximity, and they use the same antenna system simultaneously, there may be some coupling interference among the signals that are transmitted and/or received, as described earlier. In order to manage the interference between these closely located transceivers, the communication node 100 may need to find out what this interference is, or what it may be. Therefore, in this action, in order to manage the interference between the first transceiver 1 1 1 and at least the second transceiver 112, the communication node 100 determines the interference between a signal associated with the first transceiver 1 1 1 and at least a signal associated with the second transceiver 1 12. The signal associated with the first transceiver 11 1 , as defined above, may be a transmitted or received signal towards a cellular network, a wireless local area access point or station, or a received broadcast signal. The signal associated with the second transceiver 1 12, as defined above, may be a transmitted or received signal towards a cellular network, a wireless local area access point or station, or a received broadcast signal. For the sake of simplicity, the accompanying description is based on the embodiments wherein the interference occurs between a signal associated with the first transceiver 1 1 1 and a signal associated with the second transceiver 1 12. However, in other embodiments, the interference may occur between a signal associated with the first transceiver 1 1 1 and more than one signal associated with the second transceiver 1 12. The embodiments herein described, also apply to interference between a signal associated with the first transceiver 1 1 1 and more than one signal associated with the second transceiver 1 12, as one of skill in the art will appreciate.

The communication node 100 may determine the interference by several methods. In some embodiments, the communication node 100 may determine the interference by estimating the interference between the signal associated with the first transceiver 1 1 and at least the signal associated with the second transceiver 1 2. In these embodiments, the communication node 100 may calculate an estimation of the interference between the signal associated with the first transceiver 111 and at least the signal associated with the second transceiver 112. For example, in some embodiments, assuming a scenario where the signal associated with the first transceiver 1 1 1 interferes with the signal associated with the second transceiver 1 12, the communication node 100 may estimate, for a potential transmission of a first signal by the first transceiver 1 1 1 , the expected interference caused to the receiver contained in the second transceiver 1 12. This estimation may be made for each possible combination pair Ax/Ay, where Ax is the antenna that would be used by the first transceiver 1 1 for transmission, and Ay is the antenna that would be used by the second transceiver 112 for reception. Several aspects may be considered for this estimation. The coupling interference may depend on the frequency separation between the multiple signals which are simultaneously transmitted or received. In general, the coupling interference may decrease with larger spectrum separation, but this relationship may not be strict, and in general the relationship may be known. For example, a transceiver may apply a receiver filter with a certain characteristic on how signals outside the frequency range of the desired communication channel are attenuated. Thus, some aspects that may be considered for the estimation of the interference between the signal associated with the first transceiver 1 1 1 and at least the signal associated with the second transceiver 1 12 are such as the coupling gain 150 between antennas Ax Ay, possibly also the feeder loss between Ay and the second transceiver 112, and/or the coupling characteristics of the receiver in the second transceiver 112, e.g., depending on how the receiver filters signals in other frequency regions, such as in an adjacent channel. The communication node 100 may also consider the expected transmit power of the first signal by the first transceiver 1 1 1 , the feeder loss between the first transceiver 1 1 1 and antenna Ax, and the transmit filter characteristics of the first transceiver 1 1 1 on adjacent channel leakage.

In some embodiments, communication node 100 may use functional relationships to calculate the interference. For example, by using the formula: l_2 = Ptx_1 ^* F1 (f_2, f_1) * Lx ^* G(Ax;Ay) ^* F2(f_2, f_1 ), where l_2 is the interference caused by the transmitting part of the first transceiver 111 to the receiving part of the second transceiver 112, F1 is the filter leakage of the transmitting part of the first transceiver 1 1 1 into a frequency range f_ 2 for a signal transmitted in , Ptx_1 is the transmit power of the transmitting part of the first transceiver 1 11 , Lx is the feeder loss between the first transceiver 1 1 and Antenna Ax, which is assumed connected to the transmitting part of the first transceiver 11 1 , G(Ax;Ay) is the coupling gain between Antenna Ax and Antenna Ay, which is expected to be connected to the receiving part of the second transceiver 1 12, and F2(f_2, f_1 ) is the filter attenuation of the receiving part of the second transceiver 1 12 from an interfering signal in frequency band to a signal in frequency band f_2.

Alternatively or complementary to the estimations described above, the experienced interference for the second transceiver 112 caused by the first transceiver 1 11 might be measured. One example of such a measurement would be that the receiver in the second transceiver 112 detects the signal power that is received when the first transceiver 1 1 1 is transmitting. Such a measurement might be performed when the second transceiver 112 is anyway receiving or it might, preferably, be done when there is no other signal sent in the system corresponding to the second transceiver 1 12.

In other embodiments, the communication node 100 may determine the interference by obtaining information about the interference between the signal associated with the first transceiver 1 and the at (east the signal associated with the second transceiver 1 12. In these embodiments, the communication node 100 may determine the

interference, e.g., by referring to a lookup table of interference relationships, based on a priori available information, e.g., known mathematical interference relationships, pre- simulated or measured relationships stored in a table, learned relationships from previous use, which are stored in a table, etc... The relationships described above may be determined for a number of combinations of the signal/s of the first transceiver 11 1 and the signal/s of the second transceiver 1 12, and what antennas are used by the first transceiver 1 1 1 and the second transceiver 1 12, and stored in a table or expressed in a functional relationship. The interference estimate can then be derived from the functional relationship or table look-up.

In some embodiments, as part of the determination process, the first transceiver 1 1 1 may exchange information with the second transceiver 1 12 about what frequencies are being used for the communication of signals, and possibly also what transmit powers are used. This information can be exchanged via a specific interface between the two transceivers, or via a node configuration entity which is connected to both transceivers.

In other embodiments, the interference may be determined by methods other than those described here, but that will be known to those of skill in the art.

Whether the interference is estimated or obtained, the communication node 100 may manage the interference once it has already begun, or it may try to prevent it before it occurs. Therefore, in the embodiments in which the communication node 00 may try to prevent the interference from happening, it may carry out the determining the interference action in one moment which is before the interference between the signal associated with the first transceiver 1 11 and at least the signal associated with the second transceiver 1 12 takes place. In some of these embodiments, communication node 100 may estimate or obtain the interference on a regular basis, to prevent the interference from happening.

In the embodiments in which the communication node 100 may try to manage the interference once it has already begun, it may carry out the determining the interference action in one moment which is after the interference between the signal associated with the first transceiver 111 and at least the signal associated with the second transceiver 1 12 takes place. In some of these embodiments, communication node 100 may estimate or obtain the interference when a change in the communication links of the communication node takes place, such as a change in the intensity of a received signal or a change in carrier frequency or radio technology that is used.

in some cases, a certain level of interference may be determined, that should not represent a significant drop in the quality of a communication. Therefore, in some embodiments, the communication node 100 may not need to take further action, in some of other of these embodiments, the communication node 100 may repeat the

determination step to continue to monitor the interference. This may happen for example after a determined period of time has passed, or after a change in a transceiver configuration, e.g., change of frequency carrier or radio access technology, is detected, which may result in a change in the determined interference.

As mentioned earlier, in some embodiments, the first transceiver 1 1 1 may be associated with a first SIM, and the second transceiver 112 may be associated with a second S!M. In some of these embodiments, the first transceiver 111 may be associated with a first SIM profile and the second transceiver 112 may be associated with a second SIM profile. A SIM profile may provide each of the transceivers with information about at least one of: what networks the transceiver is entitled to establish a communication connection with, what radio access technologies are allowed, e.g., one or more of GSM, WCDMA, LTE, WiFi, and what frequency carriers the device is allowed. In some of these embodiments wherein the first transceiver 11 1 is associated with a first SIM profile and the second transceiver 112 is associated with a second SIM profile, the determining an interference action may be derived from signals which are permitted by the first and second SIM profiles. For example, coupling interference may be determined based on what frequency carriers are entitled to be used by the first transceiver and the relationship of those carriers with respect of the frequency carriers that are being used or entitled to be used by the second transceiver. Action 202

According to the foregoing, in some of the embodiments just described, the communication node 100 may determine the interference by comparing an interference value with a previously set interference threshold. This interference threshold may determine the interference value above which the quality of the communication signals received and/or transmitted through the communication node 100 is suboptimal according to a certain communication standard, e.g., it may not achieve a desired signal-to-noise- and-interference ratio. In other embodiments, the determined interference may be an absolute interference value that may need to be compared to a threshold, in order for the communication node 100 to determine if further action is required, or not, to manage the interference between the first transceiver 1 1 and at least the second transceiver 12.

In the embodiments in which the communication node 100 has not determined an interference between the first transceiver 1 1 1 and at least the second transceiver 1 2, which is the result of a comparison between an interference value with an interference threshold, the communication node 100 may need to take the action of establishing that the determined interference exceeds the interference threshold. This action is optional.

As described above, the outcome of this action may be that the interference threshold has been exceeded or not. If the interference threshold has not been exceeded, the communication node 100 may, in some embodiments, not take further action, as described earlier, in other embodiments, the communication node 100 may repeat the determining action again, as explained above, in the embodiments in which the interference threshold has been exceeded, the communication node 100 may carry out the following further actions. Action 203

In the embodiments in which the interference exceeds the threshold, the

communication node 100 may try to manage the potential or ongoing interference in order to provide a communication of optimal quality, in some embodiments, the communication node 100 may do this by assigning different antennas of the antenna set 120 to the first transceiver 1 11 for the purposes of transmission, and different antennas of the antenna set 120 to the second transceiver 1 12 for the purposes of data reception, in such a way that the interference is avoided altogether, or at least reduced. In some embodiments, the communication node may assign the same antennas of the antenna set 120 to the first transceiver 1 1 1 and to the second transceiver 1 12 for the purposes of transmission only. In other embodiments, the communication node may not assign the same antennas of the antenna set 120 to the first transceiver 1 1 and to the second transceiver 1 12 for the purposes of transmission. That is, the transmitting parts of the transceivers may be connected to the same antennas, but the antenna/s connected to the receiver of one transmitter must be different from the antenna/s used by the transmitter of the other transceiver, by at least one antenna.

Thus, through this action, the communication node 100 configures a first connection between a transmitting part of the first transceiver 111 and one or more first antennas of the antenna set 120 and configures a second connection between a receiving part of the second transceiver 1 12 and one or more second antennas of the antenna set 120, so that at least one antenna is different between the one or more first antennas and the one or more second antennas. This is achieved by configuring that the transmit signal output of the first transceiver 111 may be connected to said one or more first antennas and by configuring that the receipt signal input of the second transceiver 112 may be connected to said one or more second antennas, in some embodiments, this may be done by configuring the switching system 160 to carry out this configuration action.

For example, in one embodiment, the first transceiver 1 1 and the second transceiver 112 may be arranged to be connected to all antennas of an antenna set 120 having four antennas, that is, antennas 1 , 2, 3 and 4. Once the communication node 100 determines that there is or may be an interference between the transceivers, which exceeds a certain threshold, the communication node 100 may configure the transmitting part of the first transceiver 1 1 1 to be connected to antennas 1 , 2 and 3, and configure the receiving part of the second transceiver 112 to be connected to antennas 1 , 2 and 4, i.e., one antenna is different between the antennas the transmitting part of the first transceiver 1 11 is configured to be connected to and the antennas the receiving part of the second transceiver 1 12 is configured to be connected to. In another example falling within this category, communication node 100 may configure the transmitting part of the first transceiver 1 1 1 to be connected to antennas 1 , 2, 3 and 4, and configure the receiving part of the second transceiver 1 12 to be connected to antennas 1 , 2 and 3. In yet another example, the communication node 00 may configure the transmitting part of the first transceiver 1 1 1 to be connected to antennas 1 and 2, and configure the receiving part of the second transceiver 1 12 to be connected to antennas 3 and 4, i.e., all antennas are different between the antennas the transmitting part of the first transceiver 1 11 is configured to be connected to and the antennas the receiving part of the second transceiver 1 12 is configured to be connected to. As mentioned above, in some embodiments, the first transceiver 11 1 and the second transceiver 1 12 may continue to be physically coupled to all the antennas of the antenna set 120 for transmission purposes, while the connection may be effectuated by configuring the transceivers to disconnect from a selected group of antennas from the antenna set 120 for reception purposes. That is, the antenna/s used by a transceiver for transmission purposes can be different from the antenna/s used by the same transceiver for reception purposes. For the sake of simplicity only a few examples have been provided here, but they are not meant to be limiting in scope.

In some embodiments, wherein the communication node 100 comprises a switching system 160, as described above, the switching system 160 may perform the configuring the first connection between the transmitting part of the first transceiver 1 11 and the one or more first antennas of the antenna set 120, and the configuring the second connection between the receiving part of the second transceiver 1 12 and the one or more second antennas of the antenna set 120.

Each transceiver may be limited in the number of antennas that it may be configured to be connected to, which may be smaller than the entire antenna set 120. Then a selection is made for the purposes of configuring the connections. For the selection of antennas, in general, antennas are preferred which have a good radio channel to the further network nodes, such as network node 131 and network node 132. In addition, if a coupling interference is anticipated, antennas that are used for

transmission of the first transceiver 1 11 should not be identical to the antennas used for the reception of the second transceiver 12. More generally, the first transceiver 1 1 1 transmit antenna/s should have a small coupling gain to the second transceiver 1 12 receiver antenna/s.

Typically, the more the antennas are coupled, i.e., the higher the coupling gain between the antennas, the more they can lead to interference. For example, if the transmission antenna for a signal of the first transceiver 11 1 is strongly coupled to an antenna 1 and weakly to an antenna 2, the interference caused when connecting antenna 2 to the receiver of the second transceiver 1 2 may be Sower in comparison to what it would be if antenna 1 were used.

Thus, in some embodiments, the communication node 100 may base at least one of the configuring the first connection and the configuring the second connection on at least a coupling gain between the at least two antennas in the antenna set 120.

Also typically, the first transceiver 1 1 1 may want to communicate with the first network node 131 , and it would prefer antennas for this communication which have a good path gain to the first network node 131 and avoid antennas with a low path gain. The same holds for the second transceiver 1 12 and the path gain of the antennas to the second network node 132.

Thus, in some embodiments, the communication node 100 may base at least one of the configuring the first connection and the configuring the second connection on at least a path gain provided by the at least two antennas of the antenna set 120 to further network nodes.

In some embodiments, communication node 100 may base at least one of the configuring the first connection and the configuring the second connection on both, a coupling gain between the at least two antennas in the antenna set 120 and a path gain provided by the at feast two antennas of the antenna set 120 to further network nodes. In these embodiments, the communication node 100 may: a) configure the first connection between the transmitting part of the first transceiver 1 1 1 and one or more first antennas of the antenna set 120 which have good path gain to the first network node 131 , b) configure the second connection between the receiving part of the second transceiver 1 12 and one or more second antennas of the antenna set 120 which good path gain to the second network node 132, and c) avoid antenna selections in a and b when the coupling between these antennas may be high and this may leads to high interference (assuming that the signal associated with the first transceiver 1 1 and the signal associated with the second transceiver 1 12 are, e.g., close in spectrum so that they may interfere.

Action 204

In some embodiments, the first transceiver 1 1 1 may be connected to a first wireless device 171 and the second transceiver 112 may be connected to a second wireless device 172. In these embodiments, when communication node 100 has tried to manage the potential or ongoing interference by configuring the connections of each of the transceivers to a different set of antennas as described above, the communication node 100 may need to take further actions in order to implement the configuration changes on antenna connectivity of the the first transceiver 1 1 1 and the second transceiver 1 12.

In these embodiments, category and/or capability of at least one of the first transceiver 1 1 1 and the second transceiver 112 may need to be changed due to the antenna rearrangement carried out by the communication node 100. A transceiver capability includes the number of antennas a transceiver uses, !f this is changed as a result of the action of communication node 100, at least one of the first transceiver 111 and the second transceiver 1 12 may need to change its capability and signal a different capability to the network. For example, in embodiments with an antenna system with 6 antennas connected to two transceivers, for example in a car. With a configuration that each transceiver is connected to a separate set with 2 antennas to avoid interference, transceivers have a 2-antenna capability. In other embodiments, each transceiver can simultaneously be connected to 4 antennas, wherein 2 antennas are used in common between the transceivers, and 1 antenna for the first antennas is different from at least one antenna out of the second antennas, so that the transceivers have a different multi- antenna capability. A transceiver category is description of a transceiver capability which is used by, e.g., a cellular network to configure the communication channels and transmission modes that can be used for communication between the transceiver and the network.

Thus, in this action, in some embodiments wherein the interference threshold has been exceeded, and the antenna connectivity reconfigured, the communication node 100 may change in at least one of the first transceiver 11 1 and second transceiver 1 12, at least one of: transceiver category and transceiver capability, in order to adapt to the antenna connectivity change. This action is optional.

Action 205

In the embodiments in which the communication node 100 has changed in at least one of the first transceiver 1 1 1 and second transceiver 1 12, at least one of: transceiver category and transceiver capability, the communication node 100 may then inform the network node which is in communication with the transceiver whose category or capability has been changed, of this change.

Thus, in this action, the communication node 100 may send a message comprising the changed at (east one of: transceiver category and transceiver capability to a network node out of the first network node 131 and the second network node 132, wherein the network node is arranged to be connected with the at least one of the first transceiver 1 1 1 and second transceiver 1 12 which has changed the at least one of: transceiver category and transceiver capability. This action is optional.

Action 206

In yet some further embodiments in which the communication node has configured the first connection between the transmitting part of the first transceiver 1 11 and one or more first antennas of the antenna set 120, and has configured the second connection between the receiving part of the second transceiver 1 12 and one or more second antennas of the antenna set 120 in the manner described above, the communication node 100, may further try to avoid or attenuate the interference by performing further actions, such as selecting a different carrier and/or Radio Access Technology, RAT. Each of the first and second transceivers 11 1 and 1 12 is connected to a network. Typically, multiple carrier options may exist to connect to this network. A carrier is the portion of the radio frequency spectrum over which the transmission of signals takes place. For example, for embodiments using LTE access, multiple carriers may exist, e.g., at 700 MHz, 900 MHz, 1.8 GHz, 2,6 GHz, 3.6 GHz etc... But also other radio access technology, RAT, options may exist. A RAT is, e.g., UMTS/HSPA, LTE, GSM/GPRS, WiFi, WiMAX. For example, the operator that provides the further communication nodes, e.g. base stations, may have UMTS/HSPA connectivity at 2 GHz. Typically, the network controls which RAT/carrier is selected by the first and second transceivers 1 1 1 and 1 12, respectively - possibly combined also with end-user policies -. When the coupling interference exceeds a threshold, the communication node 100 may change to another carrier/RAT, so that the coupling interference is further avoided or reduced. The first transceiver 11 1 and second transceiver 1 12 in the communication node 100 may, e.g., indicate to a network a preference of certain carriers/RATs or the desire not to use certain carriers/RATs. The base station or radio network controller or access point or access controller in the network, such as any of the first network node 131 and the second network node 312, may then start Radio Resource Management, RRM, procedures so that the transceivers start measuring on other carriers/RATs and a handover procedure may be performed to a better suited carrier/RAT. In case that the possibility may not exist for a transceiver to signal carrier/RAT preferences to the further network node, the first and second transceivers 111 and 1 12 may also modify the measurement report for the channel quality of the current carrier to be perceived worse. The base station or radio network controller or access point or access controller in the network may then automatically trigger measurements on other carriers/RATs, which may lead to a re-selection of the

carrier/RAT if other suitable carriers/RATs exist at sufficient quality.

Thus, according to the foregoing, in some embodiments, the communication node 100 may determine at least one of a set of carriers and a set of RATs that may be used by at least one of the first transceiver 1 1 1 and the second transceiver 112. And the communication node 100 my determine this by one of: a) capabilities of the at least one of the first transceiver 1 1 1 and the second transceiver 1 12, and b) accessibility of the at least one of the set of carriers and the set of RATs that is enabled by a SIM configuration the at least one of the first transceiver 1 1 1 and the second transceiver 1 12 is associated with. The determination may comprise identifying combinations of permitted

carriers/RATs by the two transceivers that reduce the coupling interference and increase the antenna selection options in actions 201 , 202, 203. Action 206 is optional. Action 207

In some of these embodiments, the communication node 100 may further configure at least one of the first transceiver 11 1 and the second transceiver 1 12 to select at least one of a carrier and a Radio Access Technology, RAT, among the set of carriers and the set of RATs, respectively. This configuration comprises tuning the transceiver to the corresponding carrier and RAT and performing communication according to the procedures defined by the corresponding RAT. By implementing such an action, the interference between the first transceiver 11 1 and at least the second transceiver 112 may be avoided or reduced. Action 207 is optional. To perform the method actions in the communication node 00 described above in relation to Figure 2, for managing interference between a first transceiver 1 1 1 and at least a second transceiver 1 12, the communication node 100 may comprise an arrangement, such as that depicted in the embodiment of Figure 3. As mentioned above, the communication node 100 comprises at least the first transceiver 111 and the second transceiver 1 2, wherein the first and second transceivers 1 1 1 , 1 12 are arranged to be connected to an antenna set 120 comprising at least two antennas.

The communication node 100 comprises a processing circuit such as a processing circuit 301 depicted in Figure 3, together with computer program code for performing the functions and actions of the embodiments herein, Processing circuit 301 may comprise one or more processors. The program code mentioned above may also be provided as a computer program product, for instance in the form of a data carrier carrying computer program code for performing the embodiments herein when being loaded into the in the communication node 100. One such carrier may be in the form of a CD ROM disc. It is however feasible with other data carriers such as a memory stick. The computer program code may furthermore be provided as pure program code on a server and downloaded to the communication node 100.

in some embodiments, processing circuit 301 may be located within with at least one of the first transceiver 111 or the second transceiver 1 12. In some embodiments in which processing circuit 301 comprises more than one processor, at least one of these processors configured to carry out some or all of the functions described be!ow may be located within at least one of the first transceiver 111 or the second transceiver 1 12. In other embodiments, processing circuit 301 or all the processors comprised therein carrying out the functions described below may be located separately from any of the transceivers of communication node 100.

The processing circuit 301 is configured to determine an interference between a signal associated with the first transceiver 111 and at least a signal associated with the second transceiver 112. In some embodiments, processing circuit 301 may carry out this determination by obtaining information, as described above, that it may receive through a receiving port 302. The receiving port 302 may be a connected to one or more transceivers via some local bus or another physical connection. Once the interference has been determined, as described earlier, the processing circuit 301 may store the determined interference in a memory circuit 303, which may be in communication with the processing circuit 301 and the receiving port 302.

In some of these embodiments, the processing circuit 301 may be further configured to determine the interference between a signal associated with the first transceiver 11 1 and at least a signal associated with the second transceiver 1 12 in one moment out of: a) before the interference between the signal associated with the first transceiver 1 1 1 and at ieast the signal associated with the second transceiver 1 12 takes place, and b) after the interference between the signal associated with the first transceiver 1 1 1 and at Ieast the signal associated with the second transceiver 1 12 takes place.

in some other embodiments, the processing circuit 301 may be further configured to estimate the interference between the signal associated with the first transceiver 11 1 and at Ieast the signai associated with the second transceiver 112. As described earlier, once the interference has been estimated, the processing circuit 301 may store the estimated interference in the memory circuit 303.

In some other embodiments, the processing circuit 301 may be further configured to obtain information about the interference between the signal associated with the first transceiver 1 1 and the at Ieast the signal associated with the second transceiver 1 12. For these embodiments, the information obtained by the processing circuit 301 , such as for example, lookup tables, may be stored in memory circuit 303. Also as described earlier, once the interference has been determined by the obtained information, the processing circuit 301 may store the determined interference in the memory circuit 303. In some embodiments, the processing circuit 301 may be further configured to establish that the determined interference exceeds the interference threshold.

In some embodiments, the processing circuit 301 is further configured to configure a first connection between a transmitting part of the first transceiver 1 1 1 and one or more first antennas of the antenna set 20, and configure a second connection between a receiving part of the second transceiver 112 and one or more second antennas of the antenna set 120, when the interference exceeds a threshold, so that at least one antenna is different between the one or more first antennas and the one or more second antennas.

In some embodiments, the processing circuit 301 may be further configured to base at least one of the configuring the first connection and the configuring the second connection on at least one of: a coupling gain between the at least two antennas in the antenna set 120, and a path gain provided by the at least two antennas of the antenna set 120 to further network nodes.

In some embodiments, the communication node 100 may further comprise a switching system 304. In these embodiments, the first and second transceivers 1 1 1 , 112 may be arranged to be connected to the antenna set 120 via the switching system 304. In some of these embodiments, the processing circuit 301 comprises one or more processors, and at least one of the one or more processors is comprised in the switching system 304. In the embodiment depicted in Figure 3, the switching system 304 comprises all the processors of processing circuit 301 . However, in other embodiments not depicted, maybe one or more, but not all, of the processors of processing circuit 301 may be comprised in the switching system 304.

In these embodiments, the at least one of the one or more processors of processing circuit 301 comprised in the switching system 304 may be configured to configure the first connection between the transmitting part of the first transceiver 1 11 and the one or more first antennas of the antenna set 120, and to configure the second connection between the receiving part of the second transceiver 1 2 and the one or more second antennas of the antenna set 120.

In some embodiments, the first transceiver 1 1 1 may be associated with a first SIM and the second transceiver 1 12 may be associated with a second SIM.

In some of these embodiments, at least one of the first transceiver 1 11 and the second transceiver 1 12 may be associated with the first SIM and second SIM,

respectively, by one of: a) a remote-SIM-access connectivity that is established via a wireless technology; b) a physical connection of a SIM to the at least one of first transceiver 1 1 1 and the second transceiver 1 2; and c) a dynamic re-configuration of a software-based SIM, that is embedded in at least one of the first transceiver 11 1 and the second transceiver 1 12 and is reprogrammed with SIM credentials according to a software-based configuration procedure.

In some other of these embodiments, the first transceiver 1 11 may be associated with a first SIM profile and the second transceiver 112 is associated with a second SIM profile, and the processing circuit 301 is further configured to determine an interference by a derivation from signals which are permitted by the first and second SIM profiles.

In some other embodiments, the processing circuit 301 may be further configured to configure at least one of the first transceiver 11 1 and the second transceiver 1 12 to select at least one of a carrier and a RAT, among a set of carriers and a set of RATs, respectively.

In some other embodiments, the processing circuit 301 may be further configured to determine at least one of the set of carriers and the set of RATs by one of: a) capabilities of the at least one of the first transceiver 1 1 1 and the second transceiver 1 12, and b) accessibility of the at least one of the set of carriers and the set of RATs that is enabled by a SIM configuration the at least one of the first transceiver 11 1 and the second transceiver 1 12 is associated with.

In some embodiments, the processing circuit may be located in a vehicle, and the antenna set is located on the outside of the vehicle.

In some embodiments, the first transceiver 1 11 may be arranged to be connected to a first network node 131 and the second transceiver 1 12 may be arranged to connected to a second network node 32.

In some of these embodiments, the processing circuit 301 may be further configured to change in at least one of the first transceiver 11 1 and second transceiver 112, at least one of: transceiver category and transceiver capability.

In some other of these embodiments, the processing circuit 301 may be further configured to send a message comprising the changed at least one of: transceiver category and transceiver capability to a network node out of the first network node 131 and the second network node 132, wherein the network node is arranged to be connected with the at least one of the first transceiver 1 1 1 and second transceiver 1 12 which has changed the at least one of: transceiver category and transceiver capability. In these embodiments, the processing circuit 301 may send this message through a sending port 305, either directly, or by first storing the message in the memory circuit 303. The sending port 305 may be in communication with the processing circuit 301 , and the memory circuit 303. Memory circuit 303 may comprise one or more memory units. The memory circuit 303 is arranged to be used to store data such as the determined interference and interference lookup tables, and applications to perform the methods herein, when being executed by the processing circuit 301.

The multiple links involved in operation may operate over the same or different carriers. The multiple links may also belong to different RATs i.e. multi-RAT operation involving LTE and CD A2000. in another example the multi-RAT operation may comprise any combination of LTE, CDMA2000 1x RTT, High Rate Packet Data (HRPD), UMTS Terrestrial Radio Access (UTRA) Frequency Division Duplexing (FDD), UTRA Time Division Duplexing (TDD), and GERAN where at least 2 RATs operate from non co- located radio network nodes or base stations. In another example the RATs or carriers may carry different or same services e.g. LTE carrier may carry data whereas

CDMA2000 may carry voice service. 1xRTT is an operating mode of CDMA wireless technology. Such operation involving multiple non co-located network nodes may also belong to multipoint transmission and/or reception arrangement. It is also interchangeably called as Distributed Antenna Systems (DAS) or Common Multipoint Transmission and/or reception (CoMP). Such operation involving multiple sites may also belong to multi-carrier or carrier aggregation system.

When using the word "comprise" or "comprising" it shall be interpreted as non- limiting, i.e., meaning "consist at least of. The embodiments herein are not limited to the above described preferred embodiments. Various alternatives, modifications and equivalents may be used.

Therefore, the above embodiments should not be taken as limiting the scope of the invention, which is defined by the appending claims.