A motion detector device

[0001] The present invention relates to a motion detector device comprising a receiver adapted to receive at least one electromagnetic signal. Each received electromagnetic signal is a transmitted electromagnetic signal with the influence of a corresponding channel. Each transmitted electromagnetic signal is transmitted by a corresponding source, and this motion detector device contains predetermined information regarding each transmitted electromagnetic signal.

The present invention relates to a method of motion detection, which method comprises the step of receiving at least one electromagnetic signal. Each received electromagnetic signal constitutes a transmitted electromagnetic signal with the influence of the corresponding channel. Each transmitted electromagnetic signal is transmitted by a corresponding source.

BACKGROUND OF THE INVENTION [0003] Passive radar technology is used to detect motion and position ceilises by analyzing how transmitted signals from third party radio signal sources change over time. These sources of third party radio signals may, for example, be broadcasters of television and radio wireless communication networks, e.g. GSM.

[0004] Document W02009 / 128002 discloses a passive detector for determining the presence or movement in the environment. The detector includes a receiver with a channel estimation module adapted to determine the best channel for monitoring. The monitor is adapted to measure fluctuations in this best channel. However, there is still a need for a motion detector that increases the reliability of the detection process. [0005] Document US 2008/018521 describes how multi-threshold profiles are compared for object detection in an environment using preambles from data packets sent from a first transceiver to a second transceiver.

SUMMARY OF THE INVENTION [0006] The object of the present invention is to provide a motion detector that increases the reliability of the detection process compared to the prior art.

[0007] This object is achieved by means of a motion detector device comprising a receiver adapted to receive at least one electromagnetic signal. Each received electromagnetic signal is a transmitted electromagnetic signal with the influence of the corresponding channel. Each transmitted electromagnetic signal is transmitted by a corresponding source, and this motion detector device contains predetermined information regarding each transmitted electromagnetic signal.

[0008] This motion detector device further comprises analyzing means adapted to analyze all components of the received signal to determine how each of the corresponding electromagnetic signals affects each of its respective channel signals, by means of

- 2 of the set information. These analyzing means are also adapted to analyze the changes over time of said certain parameters over a certain time interval. This motion detector device further comprises acknowledging means adapted to determine whether said changes over time exceed a predetermined threshold value.

[0009] This cet is achieved by means of the motion detection method, which method comprises the step of receiving at least one electromagnetic signal. Each received electromagnetic signal is a transmitted electromagnetic signal with the influence of the corresponding channel. Each transmitted electromagnetic signal is transmitted by a corresponding source.

[0010] The method further comprises the steps of:

Analyzing all components of the received signal to determine how each of the corresponding electromagnetic signals affects certain parameters of each corresponding channel, by means of predetermined information relating to each of the transmitted electromagnetic signals;

analyzing changes over time of said certain parameters over a certain time interval; and determining whether said changes over time exceed a predetermined threshold value. [0011] The method is performed using a motion detector device as above.

[0012] According to one example, the motion detector device can detect the movement of surrounding objects and / or whether the motion detector device itself is moving.

[0013] According to another example, the receiver is adapted to receive at least two electromagnetic signals that have been transmitted by at least two spatially separated sources.

[0014] According to another example, the analyzing means are adapted to correlate fluctuations during the channels that result in received signals transmitted by at least two spatially separated sources. This allows the analyzing means to distinguish between surrounding objects closer to the motion detector device than any suitable source and surrounding objects closer to the respective source than the motion detector device.

[0015] According to another example, the analyzing means are adapted to produce an average channel response for a number of channel responses over a certain time interval. The analysis of changes over time of said certain parameters over a certain time interval includes an analysis of changes around this average channel response.

[0016] According to another example, changes around this average channel response include changes in amplitude of peaks and atrophies and / or the location of peaks and fades in instantaneous channel responses. These changes are included in the mentioned changes over time.

[0017] According to another example, the analysis of the time changes of said certain parameters over a certain time interval includes the analysis of Doppler shifts.

[0018] Other examples result from the dependent claims.

[0019] The present invention provides a number of advantages. Ex .:

- A complete signal is used, which makes it possible to detect fluctuations where they are most visible;

and

- All types of signal fluctuations can be taken into account.

[0020] The present invention will now be described in more detail with reference to the figures of the appended drawing, of which:

Fig. 1 shows a schematic view of the motion source and detector;

Fig. 2 shows a schematic view of three sources and a motion detector in which the object is close to the motion detector;

Fig. 3 shows a schematic view of a motion detector;

Fig. 4 shows a schematic view of a first type of fluctuation;

Fig. 5 shows a schematic view of a second type of fluctuation;

Fig. 6 shows a schematic view of three sources and a motion detector in which the object is close to the source; and

Fig. 7 shows a flow diagram of a method according to the invention.

DETAILED DESCRIPTION [0021] With reference to Fig. 1, the source of the wireless communication signal 6 sends the signal 3 to the radio wave propagation environment 9, so-called kanaiu. Referring also to Fig. 3, the motion detector 1 comprises a receiving antenna 23 and a receiver 2, wherein the receiver 2 receives the received signal 11, This received signal 11 is a transmitted signal 3 and the influence of channel 9, this influence may e.g. be due to reflections in various objects contained in channel 9.

[0022] If the position of the receiver 2 relative to the communication signal source 6 is constant, the more-influenced channel 9 components usually change relatively slowly over time, and the objects near the signal source 6 and / or the receiver 2 introduce detectable changes of the received signal 11 due to fluctuations in channel. If the motion detector 1 itself moves, new channels are present for each new position, which also results in detectable changes in the received signal 11.

In the first example, the channel 9 comprises an object 13, which object 13 affects the propagation properties of the channel 9, since the transmitted signal 3 will be reflected by this object 13, and thus this object 13 causes a difference between the transmitted signal 3 and the received signal 11 which difference varies if object 13 changes its location. It should be noted that there are probably many more objects and features of the channel 9 that cause differences between the transmitted signal 3 and the received signal 11, and, as mentioned above, the difference in cause of the object 13 varies as the position of the object 13 changes.

[0024] In the second example, the motion detector 1 itself moves, which means that there are more drastic changes in the received signal 11, because the initial channel changes into new channels for different positions of the motion detector 1 as it moves, while continuously appearing new transmission paths along with motion detector motion 1.

[0025] For these two examples, the source of the wireless communication signal 6 is in the form of a base station, and the receiver 2 is adapted to detect predetermined information contained in the received signal 11, which information is in the form of predetermined reference signals. These reference signals are known to the motion detector 1, and the data about them are stored in the memory of this motion detector 1, which allows this motion detector 1 to analyze the effect of the channel of the transmitted signal using the analysis means included in this motion detector 1.

[0026] According to the present invention, the analyzing means 10 are adapted to analyze all components of the received signal 11 to determine by means of predetermined information on how some parameters of the transmitted electromagnetic signal are influenced by the channel 9. These analysis means 10 are also adapted to analyzing changes over time of said certain parameters over a certain time interval, a number of examples of this will be discussed below.

[0027] With reference to Fig. 4 and Fig. 5, at the first selection of which certain parameters are to be analyzed, the analyzing means 10 are adapted to produce an average complex frequency response of channel 21a, 21b for a number of complex channel responses in a certain manner. time range. In this case, the analysis of changes over time of said certain parameters over a certain time interval includes analyzing the changes 14a, 14b, 14c, 14d; 15a, 15b, 15c, 15d around this median complex channel response 21a, 21b.

With reference to Fig. 4, in detecting the movement of the object 13 near the motion detector, changes around the complex mean of the channel response 21 include changes 14a, 14b, 14c, 14d of the amplitude and phase (not shown) peaks and decays in the instantaneous channel 22a responses. . This change 14a, 14b, 14c, 14d is included in a more general expression of changes over time. It should be noted that the peaks and decays 14a, 14b, 14c, 14d indicated in Fig. 4 are merely examples thereof, this figure itself contains more peaks and atrophies which have not been indicated for clarity.

[0029] With reference to Fig. 5, in motion detection, changes around the mean aggregate channel response 21 b comprise a change in the localization of peaks and decays 15a, 15b, 15c, 15d as well as the respective phases in the instantaneous responses of channel 22b. This change 16a, 15b, 15c, 15d is contained in a more general expression of changes over time.

[0030] Thus, in general, by comparing the long-term average and the instantaneous received power, potentially as a function of frequency, it is possible to detect whether the motion detector is moving. If the motion detector itself moves, the long-term medium channel changes. On the contrary, when the motion detector is stationary, only small changes of this long-term mean channel take place. This is illustrated in Fig. 4, in which the shape of the long-term medium channel is fixed, because the motion detector is stationary, and in Fig. 5 the locations of the long-term average decay and peaks are shifted because the motion detector is moving. It is therefore possible to distinguish between the motion detector movement 1 and the physical activity e.g. a person near the motion detector 1. It should be noted that the peaks and dropouts 15a, 15b, 15c, 15 indicated in Fig.

[0031] A second possibility is to perform the above analysis for a corresponding combined channel impulse response; these parameters are in fact correlated, since only Fourier transform is needed to change between the complex channel frequency response and the complex impulse response of the channel. In general, both are called a complex channel response.

[0032] A third option is to detect a Doppler shift instead. In a known manner, the frequency shift introduced into the transmitted signal 3 via the channel changes, so that doppler spreading is obtained.

[0033] In all the examples and possible solutions, the motion detector device 1 further comprises acknowledgment means 12 adapted to determine whether said changes over time exceed a predetermined threshold value. In this case, an alarm is triggered.

[0034] The motion detector can be a relatively simple device because it only has to receive signals; no adaptation to broadcasting is required. Because no access to the radio network is required, the SIM (Subscriber Identity Module) card and subscription fees do not apply.

[0035] Obviously, a conventional mobile terminal with the required functionality may be used as a motion detector. According to one example, the radio access network is adapted to communicate with the control panel for triggering alarms, but other means are also possible. For example, the motion detector can trigger surveillance measures such as cameras together with the alarm.

[0036] One example application would be to leave the motion detector 1 in the form of a user terminal, e.g. a mobile phone or a more simple device inside the car. If someone breaks into the car, an early ambulance is sent to the owner, because the movement of the object is detected nearby, in this case the thief's movement. Then, the alarm is sent when the car moves when the motion detector 1 detects that it is moving by itself. In this example, the motion detector is adapted to detect both the movement of the surrounding objects 13, and that the motion detector device 1 itself moves, but the motion detector 1 according to the present invention can be adapted to only one of these applications.

In the LTE (3GPP Long Term Evolution) LTE, each base station, an evolved Node B (eNB) node, a radio access network still transmits a cell-dependent reference, each base station being distinguishable from the other, which makes that such a network is very well suited for the present invention. The same idea applies directly to other reference signals independent of the user terminal broadcast by the eNB, such as MBSFN reference signals (MultiMedia Broadcast over a Single Freqency NetWork), positioning reference signals, synchronization signals and CSI reference signals (channe! State Information) . In one example, reference signals dependent on the user terminal for another user terminal may be used instead.

[0038] In a preferred embodiment of the present invention, with reference to Fig. 2, at least two sources of wireless communication signals transmit signals, in this case a first base station 6, a second base station 7 and a third base station 8, which base stations 6, 7, 8 are spatially separated. These base stations 6, 7, 8 belong to the radio access network R, which radio access network R eg is of the LTE type.

[0039] The first base station 6 transmits the first transmitted signal 3a, the second base station 7 transmits the second transmitted signal 4a, and the third base station 8 transmits the third transmitted signal 5a. The motion detector 2 receives the corresponding receiving signal 3b, the second reception signal 4b and the third reception signal 5b, each channel 3, 4b, 5b affected by the channel 9. In particular, a detectable object 13 is affected.

The advantage of receiving signals from a number of spatially separated sources of wireless communication signals, e.g. those of base stations 6, 7, 8, is that the detected movement, either of object 13 or of motion detector 1 itself, can be distinguished from changes channel caused by changes in the distant environment, to increase reliability. The motion can be estimated by correlating the fluctuations of different channels.

[0041] This is illustrated with reference to Fig. 6, in which the object 13 'is located near the third base station 8. Receiving signals 3b ', 4b', 5b 'from the first base station 6, the second base station 7 and the third station

Base station 8 it is possible to detect that the fluctuations that follow are caused by the object 13 'near the source of the wireless communication signal, here the third base station 8b, because in this case the object 13' will affect only channel 9 dia of the third received signal 5b, not for the other signals received 3b ', 4b'.

[0042] In other words, more generally, with reference to Fig. 2 and Fig. 6, the analyzing means 10 are adapted to correlate the received signals 3b, 4b, 5b; 3b ', 4b', 5b ', transmitted by at least two spatially separated sources of wireless communication signals 6, 7, 8, allowing analysis means to distinguish between surrounding objects 13 closer to the motion detector device 1 than any of the appropriate sources of wireless communication signal 6, 7, 8, and surrounding objects 13 'closer to any of the appropriate sources of wireless communication signal 6, 7, 8 than that of the motion detector device 1.

[0043] Another possibility with reference to Fig. 6 is that at least one of the base stations 6, 7, 8 monitors the user terminal 20 and reports changes in the radio channel of the user terminal 20. The location information is used to determine that the user terminal 20 is spatially separated from the motion detector 1.

[0044] If the user terminal 20 is spatially separated from the motion detector 1 and the time changes between them and the common subset of base stations 6, 7, 8 are correlated, it is likely that channel changes arise due to the movement of the 13 'objects in an environment nearby a base station, in Fig. 6 a third base station 8.

[0045] In other words, more generally, at least one of the sources of the wireless communication signal 6, 7, 8 is adapted to provide the motion detector device 1 with information regarding the characteristics of the signal received at the at least one user terminal 20, said user terminal 20 being spatially separated from of this motion detector device 1, wherein the analyzing means 10 are adapted to correlate said information with a common subset of received electromagnetic signals 3b, 4b, 5d for distinguishing between surrounding objects 13 closer to said motion detector device 1 than said wireless communication signal source 6, 7, 8, and the surrounding objects 13 'closer to said source of wireless communication signal 6,7, 8 than this motion detector device 1.

[0046] According to one example, this mode of operation may be transparent to the radio access network R. It may e.g. be implemented similarly to a third party application on a smartphone communicating with the server over the R access radio network. reports and measurements already supported by the standard, eg RSRP reference signal (Reference Signal Received Power), PMI (Precoder Matrix Indicator) indicator and CQI channel quality indicator (Channel Quality Indicator). In this case, the monitoring may be transparent to the user terminals and / or motion detectors. The radio access network R could also have the functionality of directly monitoring a number of user terminals 1,

[0047] Furthermore, when using a number of transmitter and / or receiver antennas it becomes possible to monitor parameters such as polarization and spatial direction, also increasing the level

- certainty, [0048] With reference to Fig. 7, the present invention also relates to a method comprising the steps of:

16: receiving at least one electromagnetic signal 3b, 4b, 5b, each received electromagnetic signal 3b, 4b, 5b being a transmitted electromagnetic signal with the influence of the corresponding channel 9; 9a, 9b, 9c, each transmitted electromagnetic signal being transmitted by a corresponding source 6, 7, 8;

17: analyzing all components of the received signal to determine how each corresponding channel 9 affects certain parameters of each transmitted electromagnetic signal; 9a, 9b, 9c, using predetermined information relating to each transmitted electromagnetic signal;

18: analyzing changes in time 14a, 14b, 14c, 14d; 15a, 15b, 15c, 15d of said certain parameters over a certain time interval; and

19: determining whether said changes in time 14a, 14b, 14c, 14d; 15a, 15b, 15c, 15d exceed a predetermined threshold.

[0049] The present invention is not limited to the above examples, but may vary from them within the limits of the scope of the claims.

[0050] LTE reference signals represent only one example and other solutions are possible. For example, other systems may be used, e.g. GSM (Global System for Mobile communication), multiple access in the field of WCDMA code (Wideband Cod Division Multiple Access) and WiFi (Wireless Fidelity), as well as other signals, e.g. a common pilot channel (CPICH, Common Pilot Channel).

[0051] The solution may be based on an existing macroscopic network or an internal building network. No additional design criteria are added over existing criteria. Motion detection is possible as long as the basic scope of the service is available. In one example, instead of already existing networks, a dedicated infrastructure is used, potentially using backward bands, e.g. on the 2.4 GHz frequency.

[0052] A particular advantage of the present invention is that all components of the received signal are used for the analysis. If only the strongest component of the channel should be used, this component could be a component with direct visibility or a reflection that is not sensitive to the movement of smaller objects in the environment, e.g. a human being or an animal. A component with direct visibility is suitable, for example, for indoor installations or for a private outdoor open space, e.g. stadium interior.

[0053] Using a number of sources, e.g. base stations and or UEs / devices, the risk of false alarms due to changes in the channel due to changes in the environment near the base station or dafeko from the UE / motion detection device (e.g., trees moving on wind) can be drastically reduced, [0054] By using reference signals based on LTE technology, channel analysis in the frequency domain is direct. In one example, portions of a channel representation in the frequency domain in which there are atrophies are selected for analysis. These parts are subject to much higher fluctuations due to changes in the environment, and are therefore suitable for higher detection sensitivity. [0055] Each source of wireless communication signal 6, 7, 8 may be in the form of any suitable source.

[0056] Any type of fluctuations caused in the channel, not only those mentioned, can be analyzed

-8powyżej.

[0057] In general, the channel response need not be aggregated and is therefore defined only as a channel response.