FIELD

The present information relates to using radar signal reflections to determine distance. BACKGROUND

The evolvement of communication technology, particularly wireless communication technology, different sensors and end user devices, has introduced versatile applications. For example, there are applications that, when run on a mobile user device, track route, velocity, timings etc. of the mobile user de- vice, and thereby also a user of the mobile user device. Typically the applications utilize location information determined by using GPS (Global positioning system) sensors. However, GPS sensors do not provide accurate enough information needed to obtain feedback required in sprint training, for example. For example, a runner wanting to obtain in situ feedback on his/her performance in interval training, such as how fast a last 10 meter interval was run or how long a distance he/she ran in five seconds, needs additional help of one or more other persons to obtain such a feedback.

BRIEF DESCRIPTION

According to an aspect, there is provided the subject matter of the in- dependent claims. Embodiments are defined in the dependent claims.

One or more examples of implementations are set forth in more detail in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims.

Some embodiments provide a method, a device, a system and a com- puter program product for providing an accurate enough feedback.

LIST OF DRAWINGS

In the following, exemplary embodiments will be described in greater detail with reference to accompanying drawings, in which

Figures 1A and IB show exemplified systems and block diagrams of devices according to exemplary embodiments;

Figures 2, 3, 4 and 8 are flow chart illustrating exemplary functionalities; Figures 5, 6 and 7 illustrate information exchange according to different examples; and

Figures 9 and 10 are schematic block diagrams.

DESCRIPTION OF SOME EMBODIMENTS

The following embodiments are exemplary. Although the specification may refer to "an", "one", or "some" embodiment(s) in several locations, this does not necessarily mean that each such reference is to the same embodiment(s), or that the feature only applies to a single embodiment. Single features of different embodiments may also be combined to provide other embodiments. Further- more, words "comprising" and "including" should be understood as not limiting the described embodiments to consist of only those features that have been mentioned and such embodiments may contain also features/structures that have not been specifically mentioned.

The present invention is applicable to any in situ motion tracking of an object, i.e. a target to be tracked. Extremely general architectures of exemplary systems are illustrated in Figure 1A and IB. Figures 1A and IB are simplified system architectures only showing some elements, and functional entities, which are logical units whose implementation may differ from what is shown.

In the embodiment illustrated in Figure 1A, the system 100 comprises a measuring device (MD) 110 as a stand-alone device, and a moving object 120, captured in a still position depicted by a dot.

In the example illustrated in Figure 1A the measuring device 110 is configured to measure (track) the motion of one or more objects 120 (only one illustrated in Figure 1A) and provide corresponding feedback. For that purpose the measuring device 110 comprises one or more radar units (r-u) 111, a feedback unit (f-u) 112, and memory 113 comprising at least settings for the feedback unit 112, and, in the illustrated example, measurements results for later retrieval. However, it should be appreciated that in another implementation measurement results, or corresponding data, is not stored, or stored only temporary, or only a certain amount of successive results are stored to the memory 113 in the measuring device. Further, the measuring device 110 comprises different interfaces 114, such as one or more user interfaces to receive user input, like the settings, and to output alarms and/or results as a feedback. The radar unit 111 is configured to send (emit) electromagnetic waves (solid curves in direction 101) in a radio or microwave domain, and receive (capture) return waves (broken curves in direction 102) reflected from the object 120 that is in a path of the emitted wave so that a distance 103 between the radar unit and the object may be determined. Typically waves are emitted dozens to hundreds of times in one second, and naturally the reflections are received at a corresponding rate, thereby making distance measurement and distance-time dependencies, for example, very accurate. The same antenna may be used for emitting waves and receiving reflected waves, or separate antennas may be used for emit- ting waves and receiving reflected waves. The radar unit may be a frequency- modulated continuous-wave radar (FM-CW), also called a continuous-wave frequency-modulated radar, that is a short-range radar capable of measuring velocity (speed) and determining a distance 103. Such a radar unit may comprise a modulated oscillator unit, a power divider unit, a high-power microwave amplifi- er connected to one or more transmitting (emitting) antennas, one or more low- noise amplifier and filtering unit connected to one or more receiving antennas, a mixer unit, an amplifier and a low-pass filter unit, and a radar control and signal processing unit.

When a short range radar is used, the beam may be a wider beam, for example 70° - 90° beam. Since waves (signals) from a single antenna will spread in all directions, and likewise a single antenna will receive signals (waves) equally from all directions, it is possible to detect and track when the measuring device comprises two or more receiving antennas more than one runner (object), as illustrated in Figure IB, assuming that the runners have different distances to the measuring device. The different distances enable that the locations may be determined based on phase difference between the reflections.

To summon up: one transmitting antenna and one receiving antenna (or one transceiver antenna) is a minimum assembly for solutions in which measuring velocity and distance is enough, whereas a minimum assembly for so- lutions in which also a direction is to be measured is one transmitting antenna and two receiving antennas. Naturally any other amount of transmitting antennas and/or receiving antennas may be used, i.e. multiple transmitting antennas and multiple receiving antennas (a so called MIMO radar). When multiple antennas are used, an antenna-specific beam may be narrower beam, for example 10° - 20° beam. Further, when two or more antennas are used, they may locate in different sides of the measuring device to expand the space where measurements may be performed. For example, in the pole vault the measuring device may be placed so that first the pole vaulter runs towards a first side of the measuring device, the first side comprising one or more radar unit, and then after vault, one or more radar units on an upper side, adjacent to the first side, measures the movement. It should be also appreciated that the movement direction of the object in relation to the emitting direction of the radar unit is not limited, any movement that takes place so that the object reflects waves back can be tracked.

The antenna beam tracking (also called scanning) can be based on analog or digital beamforming. For analog beamforming, the radar unit may comprise one or more phase shift modules (phase shifters).

Further, the radar unit, or more precisely its beam, may be directed very accurately by means of monopulse beam(s). For example, sum beams and difference beams may be used in two or more of the antennas.

The feedback unit 112 in the measuring device 110 may be combined with a radar control and signal processing unit, or the feedback unit 112 may be a separate unit configured to perform at least some of functionalities described below with Figures 2 to 8.

The embodiment illustrated in Figure IB differs from the embodiment illustrated in Figure 1A in that respect that the measuring device 110' is config- ured to measure the motion of one or more objects 120, 120' (two illustrated in Figure IB) but the feedback is provided via one or more user devices (UD) 130 the system 100' comprises.

In the embodiment illustrated in Figure IB, the measuring device 110 comprises one or more radar units (r-u) 111, and one or more different interfaces 114', such as one or more communication interfaces to communicate with a user device 130, for example. Examples of communication interfaces include, but are not limited to, a Bluetooth interface, a USB (Universal Serial Bus) interface, an optical communications interface (Light Fidelity, infrared), a wireless local area network inter-face, such as Wi-Fi (IEEE 802.11 interface) or a near field commu- nication (NFC) interface. The one or more radar units 111 may correspond to the one described above. However, in the illustrated example the one or more radar units 111 are configured to measure also a direction so that it is possible to determine distances 103, 103' of the two objects 120, 120' illustrated in Figure IB without limiting the example to such a use.

The user device 130 refers to a portable computing device (equipment, apparatus), and it may also be referred to as a user terminal, or mobile terminal. Such computing devices (apparatuses) include wireless mobile communication devices operating with or without a subscriber identification module (SIM) in hardware or in software, including, but not limited to, the following types of devices: mobile phone, smart-phone, personal digital assistant (PDA), laptop, touch screen computer, tablet (tablet computer), multimedia device, and wearable computer (wearable device). In the illustrated example, the user device is configured to provide feedback on the motion of the object. For that purpose at least one of two or more different interfaces 114' the user device comprises is a communication interface to communicate with the measuring device 110 and at least one of the two or more one is a user interface for interaction with the user. Further, the user device comprises a feedback unit (f-u) 132, and memory 133 comprising at least settings for the feedback unit 132, and, in the illustrated example, measurements results received over a communication interface 134 from the measuring device 110' for later retrieval. However, it should be appreciated that in another implementation measurement results, or corresponding data, is not stored, or stored only temporary, or only a certain amount of successive results are stored.

It should be appreciated that the measuring device 110' may be connected to the user device 130 via one of the communications interfaces 134 de- scribed above. Depending on an implementation they both may be configured to function as separate devices or the measuring device 110' may be configured to utilize processing circuitry and/or batteries of the user device 130.

Further embodiments include a distributed feedback unit in which some of the functionality described below is performed by a feedback unit in a measuring device and some of the functionality by another feedback unit in a user device.

Figures 2 to 8 illustrate exemplary functionalities of the feedback unit. Basically the feedback at the simplest may be one of a time, distance, velocity, acceleration and direction, or it may be any combination of the time, distance, veloc- ity, acceleration and direction.

Referring to Figure 2, when a user input comprising settings for the tracking, i.e. for measuring, is received in step 201, the settings are stored in step 202 to the memory. The user settings may define different rules, or thresholds, what to track/measure, etc. For example, the user settings may define "in dis- tance x meters the running velocity should be between yl and y2", or "distance to run is z meters", or "time to run is w seconds". The user settings may also define an offset illustrating thickness of the user. The user may use this when he/she is running away from the measuring device and wants to know the accurate distance he/she has run, or how long it took from the starting point to cross over a finishing line, for example. There are no limitations for the user settings, or to the rules, and thresholds defined by the rules as long as they are somehow tight with distance and/or time.

Once the settings are provided the measuring device, or if the settings are provided to a user device, the system, is ready to be used. Naturally earlier inputted settings may be used as well, if the user input indicates "use the previous settings", or the user has selected a corresponding mode using previous settings. In the example illustrated in Figures 3 to 7, it is assumed that the measuring device is stationary positioned, for example on ground, on a bench, on a table, etc., and then the measuring may start. A further assumption made in Figures 3 to 5 is that at least the analysis functionality of the feedback unit is performed in the measuring device, without restricting the solution to such an implementation. It is a straightforward action to implement the functionality to a system disclosed in Figure IB, for example by utilizing what is disclosed below with Figure 7.

Referring to Figure 3, the measuring device starts in step 301 measuring at time tO. There are several way how to trigger starting the measurement. One possibility is that the measuring device has a starting timer, and the settings contain a value for the starting timer, and when time indicated by the value for the starting timer, expires, the measuring device generates an alarm (an alarm sound, or visual alarm, such as a light, or haptic alarm) at time tO. Upon hearing/seeing/feeling the alarm the user knows that it is time to start to run, for ex- ample. Another possibility is that the measuring device detects that the user starts to move (run), since the distance is changing, and therefore the measuring is triggered. Still further possibilities include that the user device outputs a starting signal, or detects that the user starts to run (changes the movement velocity), and sends to the measuring device a starting signal that triggers the measuring. For example, a user device comprising an accelerometer can detect changes in the movement velocity. Measurements can also be triggered by an external signal caused by another device. For example, the measuring device, or the user device may comprise a microphone and be configured to trigger the measuring in response to detecting a starting pistol sound.

A sending of a signal (wave) is caused in step 302 at a time tl, and a reflected signal (wave) is received in step 303 at a time t2. From the information at least a distance between the measuring device and the object wherefrom the signal reflected back is calculated in step 304. Depending on the user settings, as well as the radar unit used, other values may be calculated as well, so that it can be checked in step 305, whether or not a threshold (th) is met. The threshold may be a time, like 10 s, or a distance, like 50 meters, or one or more velocity limits (lower, upper). Since the radar, even the simplest one with one sending antenna and one receiving antenna, measures the object's location as a function of time, one may easily calculate in addition to the distance, a velocity and/or an acceleration. Naturally more sophisticated calculation methods to determine the velocity, or a velocity data, the acceleration, or an acceleration may be used. For example, a polynomic function, such as a least square fitting or running average, may be fitted to the distance data, velocity data, and/or acceleration data. If the signal whose sending is caused in step 302 is a so called triangular FM-CW modulation signal and the received reflected frequency is determined (calculated) separately at an ascending ramp and at a descending ramp, a Doppler frequency caused by the movement speed of the object, such as a runner's speed, can be calculated, and from the Doppler frequency one can calculate directly the velocity. (In the triangular FM-CW a radio frequency is first scanned upwards and then downwards during one pulse (signal, wave) sending phase).

If the threshold is met (step 305: yes) an alerting is caused in step 306.

At the simplest the alerting may be a noise or a light outputted by the measuring device. The alerting may be also caused by sending a signal to a user device which in turns alerts, for example by vibrating, the user. It should be appreciated that any other means to alert may be used.

If the threshold is also an end event (step 307: yes), one or more results are determined and outputted in step 308. Examples of the result include a distance run (reached) in a certain time, a time it has taken to run (reach) a certain distance and a graph illustrating dependencies obtainable by the measured time and distance and direction, if the direction is measured. Examples of such graphs include a distance versus time, velocity versus distance, velocity versus time, acceleration versus distance, acceleration versus time and acceleration versus velocity, just to mention few. The feedback unit may be configured to provide a user a possibility to further analyse the outputted result. For example, a distance versus time graph may include a possibility to obtain velocity and/or accel- eration information at a specific spot on the graph. Naturally an event that is considered to be an end event depends on the settings. Examples of an end event in- elude expiry (lapse) of a time indicated in the settings, a specific distance has been reached, a specific user input indicating end of the measurement, detecting that the object has not moved within a certain time period and/or detecting that no reflections are received.

It should be appreciated that instead of, or in addition to, determining and outputting the one or more results by the measuring device, sending measurement results to the user device and/or to a data storage in a cloud or Internet, for example, may be caused in step 308. In such a case the user device may be configured to determine and output one or more results.

Depending on an implementation, measurement results, or results determined in step 308, or in a user device, may be stored for later evaluations.

If the threshold is not also an end event (step 307:no), the process returns to step 302 to cause sending of a further signal. For example, if the runner is running too slow or too fast, an alert is caused in step 306 to guide the runner to run at a proper velocity, while continuing the measuring. Examples of a threshold being an end event include that the pre-set distance has been reached (moved) and that the pre-set time from the start has lapsed.

If the threshold is not met (step 305: no), the process returns to step 302 to cause sending of a further signal.

Figure 4 is illustrating an example in which the radar unit comprises at least two receiving antennas so that it is capable of 3 dimensional measuring, i.e. measuring in addition to a distance also a direction in three dimensions (in 3 D space), the direction being measured against center line of the radar signals (pulses), for example.

Referring to Figure 4, the measuring device starts in step 401 measuring at time tO. As described above, there are several ways which may trigger the starting. However in the example illustrated it is assumed that the measuring starts after a certain time has lapsed from the user inputting user settings. Therefore an alerting is caused in step 402 at time tO, as well as a sending of a signal (wave) is caused in step 403 at a time tO. By doing so it is possible to measure reaction time, for example. As said above, the alert may be a noise, resembling a gunshot or whistle, for example, or a vibration caused to a user device.

Then a reflected signal (wave) is received in step 404 at a time tl. From the information a 3 dimensional distance between the measuring device and the object wherefrom the signal reflected back is calculated in step 405, and as said above with Figure 3, also other values can be calculated as well. The 3 di- mensional distance is actually a set of distance values wherefrom contours of objects reflecting the waves back may be determined. That means that a step height and/or movement position (running position, standing position, etc.), for example, may be determined. In the illustrated example, once the one or more values are calculated, it is checked in step 406, whether or not an alert threshold (th) is met. As said above, the threshold may be a time, like 10 s, or a distance, like 50 meters, or one or more velocity limits (lower, upper).

If the alarm threshold is met (step 406: yes) an alerting is caused in step 407. Since the time interval between tO and tl is very short the alerting may in the beginning appear to a user as a continuous alert, if he/she has not started to move, for example. That may happen, for example, if the thresholds define upper and lower limits for the velocity.

If the alert threshold is also an end event (step 408: yes), such as the lapse of running time or detecting that the distance indicated by the user settings, for example inputted as a specific distance from the measuring device or as a difference between ending distance or starting distance, one or more results are determined, as indicated by the user settings, for example, and outputted in step 409. Different examples of results are given above. The 3-dimensional distances allow more versatile results to be outputted. Examples of such include a running pattern illustrating running by twists and turns and mediate step height. Further, if the measuring is started a little bit earlier than the first alarm is caused, one may output how stabile the runner was while waiting for the start alarm (first alarm), and how fast he/she reacted to the start alarm. Still another example is outputting the amount of steps taken.

It should be appreciated that instead of, or in addition to, determining and outputting the one or more results by the measuring device, sending measurements and/or results to the user device and/or to a data storage in a cloud may be caused in step 409, for example for later evaluations.

If the alarm threshold is not also an end event (step 408: no), the pro- cess returns to step 403 to cause sending of a further signal.

If the alarm threshold is not met (step 406: no), the process proceeds to step 408 to check whether or not an end event is detected.

In the example illustrated in Figure 5 it is assumed that the measuring device (EQUIP) receives reflections from two different objects, targetl and tar- get2, that are apart from each other at least so that there will be a phase difference in the reflections, the minimum distance between the objects depending on the bandwidth of the radar. The minimum distance between two objects to be reliable detected as separate objects is a resolution cell (AR) of the radar, which is determined using following formula: AR = c/2BW where

c is the velocity of light, and

BW is the bandwidth

Referring to Figure 5, in the illustrated example it is assumed that the measuring device (equipment, EQUIP) comprises a user interface via which user settings are received in point 5-0, one of the user settings triggering sending from the radar unit of the measuring device EQUIP a signal 5-1, which results receiving a reflected signal 5-2 from the targetl and a reflected signal 5-2' from the target2. Corresponding information is temporarily stored in point 5-3 to the memory, and one or more values needed for the above described threshold comparison, and/or for detecting an end of measurement are calculated in point 5-3 for each target separately based on detected phase difference. Sending of a signal 5-1, receiving reflected signals 5-2, 5-2', temporarily storing and calculating are repeated until the goal (end of measurement) is reached (point 5-3'). It should be appreciated that user settings, or preset settings may define that only reflections received within a specific direction are taken into calculation process, or that only those targets that are moving are tracked, or those targets that are moving to the indi- cated direction (towards the measuring device, away from the measuring device) are tracked.

In the illustrated example, when the goal is reached information on different results from the targets are outputted on the user interface of the measuring device, and then storing the temporarily stored information, possible also calculated values, to a data storage in a cloud is caused (point 5-3'). Thereafter temporarily stored information may be, once sent, to be deleted from the memory.

Although in the example illustrated in Figure 5 two targets are tracked, the same principles can be used to track plurality of objects.

Figure 6 is a chart illustrating information exchange in an exemplified implementation in which a partly distributed functionality of the feedback unit is utilized. However, it should be appreciated that the same principles may be used with a feedback unit only either in the measuring device or in the user device, and with any other intermediate solution.

Referring to Figure 6, in the illustrated example it is assumed that the measuring device (equipment, EQUIP) comprises a user interface via which different sets of settings, stored to the memory, are outputted in point 6-0 to the user, and a user input selecting one of the settings is received in point 6-0. In other words, the user is provided with different alternative measurement schemes, one of which is selected.

A further assumption in the illustrated example is that selection of the settings to be used (point 6-0) also triggers sending from the radar unit of the measuring device EQUIP a signal 6-1, which results receiving a reflected signal 6- 2 from the target (object to be tracked). Corresponding information is temporarily stored in point 6-3 to the memory, and one or more values needed for the above described threshold comparison, and/or for detecting an end of measurement are calculated in point 6-3. Sending of a signal 6-1, receiving a reflected signal 6-2, temporarily storing and calculating are repeated until the goal (end of measurement) is reached (point 6-3'). Then the stored information, possible also calculated values are transmitted in one or more messages 6-4 to a user device UD. The temporarily stored information may be, once sent, to be deleted from the memory.

The user device UD calculates in point 6-5 one or more results, as described above, and outputs them in point 6-5. Naturally the results and/or the information received in message (s) 6-4 may be stored to a memory of the user device, or to a cloud, for later analysis.

By using two or more measuring devices it is possible to increase the accuracy of the measurements and/or the distance over which the measurements may be carried. Such a situation is illustrated in Figure 7. A further assumption made in Figure 7 is that the feedback unit functionality is implemented in the user device, the measuring devices performs mere measuring. However, the idea of having two or more measuring devices may be implemented with a distributed feedback functionality.

Referring to Figure 7, two measuring devices, EQUIP1 and EQUIP2 are placed and started in point 7-0. Both of them transmits at certain intervals a sig- nal (wave) 7-1, 7-1', receives its reflection 7-2, 7-2', and measurement results in messages 7-3, 7-3' to a user device UD. Each measuring device sends in messages 7-3, 7-3' at least time and distance information, possibly also direction information. The user device UD then stores in point 7-4 the received measurement results, performs in point 7-4 one or more of the above described calculations for the above described threshold comparison and/or for detecting an end of meas- urement, and naturally comparison (s) and eventually detecting the end of measurement, and ending the measurement. After the end of the measurement, or depending on an implementation/settings, also during the measurement (motion tracking) one or more of the results described above will be determined and out- putted on the user interface, the outputting including alerting.

Naturally the process described with Figure 7 may be implemented when one measuring device is used, or when a plurality, like three, four, five, etc., of measuring devices are used. Further, using a plurality of measuring devices it is easier to track (monitor) two or more objects, since it is very unlikely that two objects not being side by side have the same distance to all measuring devices.

It is also possible that instead of the measuring devices sending measurement results to the user device, the measuring devices send the measurement results to each other, and each measuring device performs the functionality described in Figure 7 with the user device, or one of the measuring devices is a so called master measuring device whereto the measurement results are sent, the master measuring device performing the functionality of the user device.

Figure 8 is a flow chart illustrating how the measured information/data can be utilized for different evaluation purposes. For example, a feedback unit in the measuring device or in a user device may be configured to perform such a process. Naturally the process may be performed by another unit in the user device, or by a separate device configured to analyze and/or evaluate measurement results.

Referring to Figure 8, when it is detected in step 801 that an analysis is started, stored data is retrieved in step 802 from the data storage where it is stored. As is evident from the above, the data may be stored to the measuring de- vice, to the user device, or to an external data storage, such as a cloud or to the Internet. Depending on an implementation the data retrieved may be all data stored, data that has not been retrieved earlier, data with certain age, etc.

In the example it is assumed that a plurality of different analyses may be performed to the data. Examples of different analyses include the above de- scribed ways to obtain wanted results, and synchronizing the data with information collected by other means, such as a pulse counter, a camera, a video cam- era, and using the data to evaluate exercise (running, walking, jumping, gymnastic, cycling, etc.) results, compare competitors results, etc., in addition to what has explained above. Therefore in step 803 it is determined which one of the plurality of different analyses is selected. Then the analysis is performed and analysis re- suits outputted in step 804.

Further, in the illustrated example, the user is provided a possibility to end the analyzing or to continue with a different analysis. The user interface may display the alternatives while outputting the results, for example. If after output- ting the result, a user input indicating end (step 805: yes) is received, the exem- plary process ends by storing the analysis results generated during the processing to history part of data. It should be appreciated that there is no need to store the results.

If after outputting the results a user input indicating selecting another analysis (step 805: no), the process continues to step 803 to determine the select- ed analysis.

As is evident from the above, the use of radar to measure movement, and alert in situ according to meeting one of one or more of user settings provides feedback in versatile situations, such as training regardless of the sport exercised. Further, in addition to sport the above may be used for other purposes that need in situ feedback at least in form of an alarm about movement, including staying stationary, of a target.

The steps, points, information exchange (messages) and related functions described above in Figures 2 to 8 are in no absolute chronological order, and some of the steps/points may be performed simultaneously or in an order differ- ing from the given one. Other functions can also be executed between the steps/points or within the steps/points, or after the steps/points, and other information may be sent. Some of the steps/points or part of the steps/points can also be left out or replaced by a corresponding step/point or part of the step/point.

The techniques and methods described herein may be implemented by various means so that a device configured to support providing feedback on motion, based on at least partly on what is disclosed above with any of Figures 1A to 8, including implementing one or more functions of a corresponding measuring device and/or user device described above with an embodiment/example, for example by means of any of Figures 2 to 8, comprises not only prior art means, but also means for implementing the one or more functions/operations of a cor- responding functionality described with an embodiment, for example by means of any of Figures 2 to 8, and it may comprise separate means for each separate function/operation, or means may be configured to perform two or more functions/operations. For example, one or more of the means and/or the feedback unit, or its sub-units if a distributed solution is used, described above may be implemented in hardware (one or more devices), firmware (one or more devices), software (one or more modules), or combinations thereof. For a hardware implementation, the device(s) of embodiments may be implemented within one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, logic gates, other electronic units designed to perform the functions described herein by means of Figures 1A to 8, or a combination thereof. For firmware or software, the implementation can be carried out through modules of at least one chipset (e.g. procedures, functions, and so on) that perform the functions described herein. The software codes may be stored in a memory unit and executed by processors. The memory unit may be implemented within the processor or externally to the processor. In the latter case, it can be communicatively coupled to the processor via various means, as is known in the art. Additionally, the components of the systems described herein may be rearranged and/or complemented by additional components in order to facilitate the achievements of the various aspects, etc., described with regard thereto, and they are not limited to the precise configurations set forth in the given figures and description, as will be appreciated by one skilled in the art.

Figure 9 provides a measuring device (apparatus) configured to carry out the functions described above in connection with the measuring device. Each device may comprise one or more control circuitry, such as at least one processor 902, at least one memory 904, including one or more algorithms 903, such as a computer program code (software), and one or more radar circuitry 905, wherein the at least one memory and the computer program code (software) are configured, with the at least one processor and the one or more radar circuitry, to cause the apparatus to carry out any one of the exemplified functionalities of the measuring device. The measuring device may further comprise different interfaces 901, such as one or more radar antennas for sending radar pulses (signals, waves) and/or for receiving reflections, one or more user interfaces for user interaction, and one or more communication interfaces (TX/RX) comprising hard- ware and/or software for realizing communication connectivity according to one or more communication protocols.

Figure 10 provides a user device (apparatus) configured to carry out one or more of the functions described above in connection with the user device. Each user device may comprise one or more control circuitry, such as at least one processor 1002, and at least one memory 1004, including one or more algorithms 1003, such as a computer program code (software), wherein the at least one memory and the computer program code (software) are configured, with the at least one processor, to cause the apparatus to carry out any one of the exempli- fied functionalities of the user device. The user device may further comprise different interfaces 1001, such one or more user interfaces for user interaction, and one or more communication interfaces (TX/RX) comprising hardware and/or software for realizing communication connectivity according to one or more communication protocols.

Referring to Figures 9 and 10, at least one of the control circuitries in the corresponding device 900, 1000 is configured to provide the feedback unit, or its sub-unit in a distributed solution, and to carry out functionalities described above by means of any of Figures by one or more circuitries.

The memory 904, 1004 may be implemented using any suitable data storage technology, such as semiconductor based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory.

The different interfaces 901, 1001 may comprise standard well-known components such as an amplifier, filter, frequency-converter, (de) modulator, and encoder/decoder circuitries and one or more antennas. The communication interfaces may comprise radio interface components providing the network node and the terminal device with radio communication capability in the cell.

The methods described in connection with Figures 2 to 8 may be carried out by executing at least one portion of a computer program comprising cor- responding instructions. The computer program may be in source code form, object code form, or in some intermediate form, and it may be stored in some sort of carrier. For example, the computer program may be stored on a computer program distribution medium readable by a computer or a processor. The computer program medium may be, for example but not limited to, a record medium, com- puter memory, read-only memory, and software distribution package, for example. The computer program medium may be a non-transitory medium. Coding of software for carrying out the embodiments as shown and described is well within the scope of a per-son of ordinary skill in the art.

Even though the invention has been described above with reference to examples according to the accompanying drawings, it is clear that the invention is not restricted thereto but can be modified in several ways within the scope of the appended claims. Therefore, all words and expressions should be interpreted broadly and they are intended to illustrate, not to restrict, the embodiment. It will be obvious to a person skilled in the art that, as technology advances, the inventive concept can be implemented in various ways. Further, it is clear to a per- son skilled in the art that the described embodiments may, but are not required to, be combined with other embodiments in various ways.