Joint radar communication

Abstract

The present invention is related to a joint radar communication system within a wireless communication environment, comprising at least one processor, at least one transceiver configured to transmit a radar signal by which azimuth data is sent together with radar waveform, at least one receiver configured to receive echoes of the radar signal, and at least one memory communicatively coupled to the at least one processor. The transceiver is configured to transmit a joint radar communication signal (JRC), and the receiver is configured to use a joint radar communication channel to receive echoes of the radar signal, and to transmit a communication (JRC) signal.

Description

DescriptionJoint Radar CommunicationThe present invention relates to a joint radar communication system and method.Millimeter-wave based communications is key to support very high data rates (generated by massive automotive sensing) and high capacity in Vehicle-to- Vehicle (V2V) and Vehicle-to-lnfrastructure (V2I) scenarios. Beam-management, particularly beam-alignment is fundamental to enable mmW-based (mmW) V2X. The notion of Signals of Opportunity (SoO) to enable passive radar has been investigated in the context of Long-Term Evolution (LTE) technology. However, in a beamforming scenario, such as New Radio operating in Frequency Range 2 (FR2) or mmW-based V2V, the potential benefit of this concept has not been fully explored.Existing literature addresses the notion of Signals of Opportunity (SoO) and the general framework of beam management independently. Join Radar and Communication (JRC) is another emerging paradigm which has, to the best of the knowledge of the inventors, recently been proposed to make a better and more efficient use of the radio resources statically allocated to radar systems.Relevant publications are listed below:

[0001] R. S. Thoma, C. Andrich, G. D. Galdo, M. Dobereiner, M. A. Hein, M. Kaske, G. Schafer, S. Schieler, C. Schneider, A. Schwind, and P. Wendland, "CooperativeInternalPassive Coherent Location: A Promising 5G Service to Support Road Safety," IEEE Communications Magazine, vol. 57, no. 9, pp. 86-92, 2019.[2] D. Pastina, F. Santi, F. Pieralice, M. Antoniou, and M. Cherniakov, "Passive Radar Imaging of Ship Targets with GNSS Signals of Opportunity," IEEE Transactions on Geoscience and Remote Sensing, pp. 1-16, 2020.[3] S. Bartoletti, A. Conti, and M. Z. Win, "Passive radar via LTE signals of opportunity, “ in 2014 IEEE International Conference on Communications Workshops (ICC), pp. 181 -185, 2014.[4] A. Ali, N. Gonzalez-Prelcic, and A. Ghosh, 'Automotive radar radiations as signals of opportunity for millimeter wave V2I links," in 2019 53rd Asilomar Conference on Signals, Systems, and Computers, pp. 554-558, 2019.[5] S. Lagen, L. Giupponi, B. Bojovic, A. Demir, and M. Beluri, "Paired Listen before Talk for Multi-RAT Coexistence in Unlicensed mmWave Bands," in 2018 IEEE International Conference on Communications Workshops (ICC Workshops), pp. 1-6, 2018.Patent literature also addresses beam management. US 2022094511 A1 discloses an electronic device and methods for performing beam management (BM) in systems with antenna arrays capable of operating in combined radar and communication modes are disclosed herein. The electronic device comprises a processor and a plurality of antenna elements configured to operate in a first mode, in which the antenna elements are used for communications with beamforming, and a second mode, in which at least two of the antenna elements are used for radar and the remainder are used for the communications. The processor is configured to perform a mode switch on the antenna elements to switch between the first mode and the second mode, determine, after the mode switch, a new beam to use during a first beam management cycle, perform, using the new beam, the first beam management cycle to obtain signal quality measurements, and perform a second beam management cycle using an updated beam based on the signal quality measurements. KR100813909 B1 describes an automotive radar dual mode system with a wireless communication function is provided to improve sensitivity as using a low-cost antenna by simplifying a frequency conversion system. The automotive radar dual mode system includes a signal processor, that has a radar mode and a communication mode. In the radar mode, distance, speed and azimuth angle are measured by using Digital Beam Forming to a converted radar signal among digital signals outputted from a radar receiver. In the communication mode, compensation of location of a vehicle or information exchange between vehicles is performed by analyzing a converted communication signal among the digital signals. CN104881995 A discloses a road-side dual beam microwave radar traffic flow detection device and a road-side dual beam microwave radar traffic flow detection method. The road-side dualbeam microwave radar traffic flow detection device comprises a first antenna, a second antenna, a first microwave transceiving module, a second microwave transceiving module, a waveform generating module, an intermediate frequency filtering module, an acquisition module, a digital co-processor, a digital main processor and a communication interface. The first antenna and the second antenna are placed on the road-side and vertical to the lane direction for transmitting and receiving microwaves, a digital signal processor acquires echoes, and the digital main processor and the digital co-processor conduct statistical calculation on traffic flow, occupation ratio and average vehicle speed.As reflected by patent literature, pure radar-based beam alignment is mainly based on signal processing (e.g., Angle-of-Arrival (AoA), road-side unit (RSU) processing of automotive radars, etc.). Inventions based on out-of-band signaling (Signal-of-Opportunity SoO) are focused mainly on inter-communication bands, e.g., communication systems operating in different bands (sub-6 and mmW).When addressing beam alignment using radio resources of the communication network (e.g., 5G), and in the case of analog beamforming, the process takes some time, besides to the fact that those resources are statically allocated for this purpose. The concept of signal of opportunity is strongly connected with the principle of passive radar, and for that reason has found certain applications in beam management. However, in this case, both functionalities belong to different systems, which has implications from implementation point of view., i.e., both systems need to be connected and fast and reliable connectivity must be guaranteed. The principle behind the proposed solution is to have both functionalities tightly integrated within the same system by means of joint radar communication techniques.Therefore, the technical problem to be solved, in this context, is how to pair transmission and reception for mmW-based systems using radar signals.It is an object of the present invention to provide a system of joint radar communication, and a correspondent method of joint radar communication according to independent claims.According to a first aspect of the invention, there is provided a joint radar communication system within a wireless communication environment, comprising at least one processor, at least one transceiver configured to transmit a radar signal by which azimuth data is sent together with radar waveform, at least one receiver configured to receive echoes of the radar signal, and at least one memory communicatively coupled to the at least one processor. The transceiver is configured to transmit a joint radar communication signal, and the receiver is configured to use a joint radar communication channel to receive echoes of the radar signal, and to transmit a communication signal.The invention aims at providing faster and resource efficient mechanisms to address beam-management, particularly beam alignment. Beam alignment refers to the process by which transmission unit and reception unit determines the appropriate direction (beamforming) to communicate with each other. This is particularly necessary when operating in higher frequencies and challenging when mobility is considered. Additional data may be transmitted together with the sensing signal (i.e., radar signal), e.g., parameters are transmitted to be used for collision-free channel access.In one embodiment, the joint radar communication signal is a radar signal carrying data or a communication signal with radar capabilities.In one further embodiment, in case the transceiver and / or receiver belong to a stationary unit, such as an enhanced road-side unit, the transceiver belonging to the enhanced road-side unit is able to transmit both joint radar communication signal and communication signal, and the receiver belonging to the enhanced road-side unit is able to receive and process echoes of the transmitted joint radar communication signal and to receive communication signal.Moreover, in case the transceiver and / or the receiver belong to a mobile unit, such as an automotive radar system mounted on a vehicle, the transceiver belonging to the mobile unit is able to transmit both joint radar communication signal and communication signal, and the receiver belonging to the mobile unit is able to receive and process the data inserted in the transmitted joint radar communication signal and to receive communication signal.According to a second aspect of the invention, there is provided a method of joint radar communication within a wireless communication environment, performed by means of at least one processor, at least one transceiver, at least one receiver, and at least one memory communicatively coupled to the at least one processor. The method comprises the following steps: at transceiver, transmitting a joint radar communication signal including at least azimuth data together with radar waveform; at receiver, direction and identity of the transceiver is obtained from the azimuth data, and radar echoes are reflected; at transceiver, the reflected radar echoes are processed, and radar detection operations based on the reflected echoes are performed. At receiver, a joint radar communication signal is transmitted via a joint radar communication channel.The main idea behind the invention is using joint radar communication as a mechanism to provide a solution for fast beam management without need for dedicated resources for that (an existing radar channel is employed). From the sensing unit perspective (radar TX), the operation is conventional, except that radar radiations include, at least, directional information that can be used by the receiver unit (the target from the sensing perspective) to immediately transmit data to the TX unit in the appropriate direction. In this manner, the radar unit is “telling” possible communication peers “how to reach me”, while performing its own regular radar and sensing tasks.In some embodiments of the inventive method, the joint radar communication signal is either a radar signal carrying data or a communication signal with radar capabilities. Furthermore, the radar signal carries spatial, vectorial data transmitted out-of-band through automotive radar signals. The communicationsignal also include data about communication channel(s) to be used for, at least, beam alignment, described by, at least, time-frequency-resources or access parameters.According to another embodiment, in case the transceiver and / or receiver belong to a stationary unit, such as an enhanced road-side unit, joint radar communication signal and communication signal are both transmitted by the transceiver belonging to the enhanced road-side unit, and echoes of the transmitted joint radar communication signal and to receive communication signal are recived and processed by the receiver belonging to the enhanced road-side unit.Moreover, in case the transceiver and / or the receiver belong to a mobile unit, such as an automotive radar system mounted on a vehicle, both the joint radar communication signal and the communication signal are transmitted by the transceiver belonging to the mobile unit, and the data inserted in the transmitted joint radar communication signal and the communication signal are received and processed by the receiver belonging to the mobile unit. In some embodiments wherein the method is configured as part of data communication service, the radar data are spatial, vectorial data transmitted out-of-band through automotive radar signals.According to further embodiments, the communication signal sent by receiver are MAC-related information for vehicle-to-infrastructure (V2I), infrastructure-to-vehicle (12V) or vehicle-to-vehicle (V2V) communication in one shot. In further embodiments, the communication signal sent by receiver are assigned to a predetermined spectrum or frequencies or is based on a per-service priority token, unassigned to a spectrum or frequencies.Another aspect of invention is providing a non-transitory computer-readable storage medium storing instructions that, when executed by one or more processors, causes the one or more processors to perform operations of the method according to invention.Further special features and advantages of the present invention can be taken from the following description of advantageous embodiments by way of the accompanying drawings.FiguresFIG. 1 illustrates an operating environment for a joint radar communication system,FIG. 2 is the pictorial representation of beam alignment between a transmission unit and a reception unit,Fig. 3 is a block diagram illustrating how a joint radar communication channel is used to transmit data / information, according to invention,Fig. 4 presents a first embodiment of invention, namely a V2I use case of a joint radar communication-based beam management system according to invention, Fig. 5 presents a second embodiment of invention, namely a V2V use case,Fig. 6 illustrates a flowchart of a method of joint radar communication, according to invention.Detailed descriptionFor a better understanding of the principles of the present invention, embodiments of the invention will be explained in more detail below with reference to the figures. Like reference numerals are used in the figures for the same or equivalent elements and are not necessarily described again for each figure. It is to be understood that the invention is not limited to the illustrated embodiments and that the features described may also be combined or modified without departing from the scope of the invention as defined in the appended claims.As referred to herein, an ..automotive radar" include a radar transmitter unit Tx configured to transmit radar waveforms having a radar carrier frequency towards a scene and a radar receiving unit Rx that is configured for receiving radar waveforms that have been transmitted by the radar transmitter unit Tx and have been reflected by a target in the scene. The automotive radar has also means for decoding information from the radar waveforms received by the radar receiving unit Rx. An automotive radar may be stationary (integrated in traffic infrastructure) or mobile(mounted on-board of vehicles, each vehicle being equipped with several radar sensors dedicated to specific driving assisting functions, for example).Furthermore, the term of ..enhanced road-side unit" means a DSRC (Dedicated Short Range Communications) transceiver mounted along a road or pedestrian passageway, being part of traffic infrastructure (as stationary unit), or mounted on a vehicle or hand-carried (as a mobile unit), and providing connectivity and information support to mobile units (e.g., passing vehicles), while being able to sustain outdoor edge computing applications, functions or capabilities ranging from smart city, traffic management. V2E (Vehicle-to-Everything) without the restrictions imposed to ..classic" road-side units (which are either restricted to the location where they are licensed to operate, or where do not interfere with a site- licensed operation).Various embodiments described herein are generally directed to techniques of joint radar communication within a wireless communication environment.In the following, the exemplary scenario shown in Figure 1 is used to further explain how operates the system according to invention. Fig. 1 illustrates an exemplary number of vehicles V arbitrarily deployed or navigating within a wireless communication environment, being equipped with on-board means of conventional communication (schematically illustrated, not referenced) such as 4G and / or 5G (cellular) communication capabilities, e.g., llu or sidelink, able to communicate with infrastructure units, such as road-side units integrated in traffic infrastructure, for example, as road-side units on which stationary automotive radars may be mounted in order to monitor traffic in intersections or along roads. Further on. at least some of the illustrated vehicles are assumed to be equiped with at least one automotive radar, and this at least one automotive radar comprises transmision Tx and reception Rx units - in other words, a multitude of automotive radars.Fig. 2 presents the concept of conventional radar beam alignment, as discussed in the background of this description.Fig. 3 illustrates an embodiment of a joint radar communication system, according to invention. The joint radar communication system comprises at least one processor, at least one transceiver configured to transmit a radar signal by which azimuth data is sent together with radar waveform, at least one receiver configured to receive echoes of the radar signal, and at least one memory communicatively coupled to the at least one processor. The transceiver is configured to transmit a joint radar communication signal, and the receiver is configured to use a joint radar communication channel to receive echoes of the radar signal, and to transmit a communication signal.In one embodiment, the joint radar communication JRC signal is a radar signal carrying data. For example, the data carried by the radar signal are bits with at least azimuth data (vector information) readable by “targets”, such targets using this information to transmit directional (pure communication) signals (beamformed) directly. Example of possible targets are: a receiver according to invention, or any other entity (comprising a receiver according to invention.In another embodiment, the joint radar communication JCR signal is a communication signal with radar capabilities; more precisely, a communication signal comprising data about communication channel(s) described by timefrequency resources, access parameters (e.g., preambles or sequences to be used etc.). The communication chnnel(s) described like that are to be used for beam alignment.The transceiver and / or receiver belong to a stationary unit, such as an ehnanced road-side unit eRSU, or a mobile unit, such as an automotive radar system mounted on a mobile platform, such as a vehicle. In the context of this invention, an enhanced road-side unit is a road-side unit with dual-functional radar communication capabilities, meaning a road-side unit capable to receive, ..understand" and transmit further a joint radar communication signal JRC.Fig. 4 shows a V2I embodiment of the inventive system featuring the case wherein the transceiver and / or receiver belong to a stationary unit, such as an enhanced road-side unit eRSU. The transceiver belonging to the enhanced road-side unit isable to transmit both joint radar communication signal JRC and communication signal COM, and the receiver belonging to the enhanced road-side unit is able to receive and process echoes of the transmitted joint radar communication signal JRC and to receive communication signal COM. The enhanced road-side units eRSUs are connected in a network, and the network is either a cellular network, a wireless network, a radio-based network, a telephone network, a satellite network, a wired network, a fiber optic network, or a combination thereof.Fig. 5 illustrates a V2V embodiment of the inventive system featuring the case wherein the transceiver and / or the receiver belong to a mobile unit, such as an automotive radar system mounted on a vehicle. The transceiver belonging to the mobile unit is able to transmit both joint radar communication signal JRC and communication signal COM, and the receiver belonging to the mobile unit is able to receive and process the data inserted in the transmitted joint radar communication signal JRC and to receive communication signal COM.Fig. 6 displays an embodiment of the method according to invention. The method comprises:S1 at transceiver, transmitting a joint radar communication signal including at least azimuth data together with radar waveform,52.1 at receiver, direction and identity of the transceiver is obtained from the azimuth data, and radar echoes are reflected, at transceiver, the reflected radar echoes are processed, and radar detection operations based on the reflected echoes are performed,52.2 at receiver, a joint radar communication JRC signal is transmitted via the joint radar communication channel.In case the transceiver and / or receiver belong to a stationary unit, such as an enhanced road-side unit eRSU, joint radar communication signal JRC and communication signal COM are both transmitted by the transceiver belonging to the enhanced road-side unit, and echoes of the transmitted joint radar communication signal JRC and to receive communication signal COM are recived and processed by the receiver belonging to the enhanced road-side unit eRSU.In case the transceiver and / or the receiver belong to a mobile unit, such as an automotive radar system mounted on a vehicle, the joint radar communication signal JRC and the communication signal COM are both transmitted by the transceiver belonging to the mobile unit, and the data inserted in the transmitted joint radar communication signal JRC and the communication signal COM are received and processed by the receiver belonging to the mobile unit.When the method is configured as part of data communication service, the radar data are spatial, vectorial data transmitted out-of-band through automotive radar signals.The communication signal sent by receiver are MAC-related information for vehicle- to-infrastructure V2I, infrastructure-to-vehicle I2V or vehicle-to-vehicle V2V communication in one shot, or is assigned to a predetermined spectrum of frequencies or is based on a per-service priority token, unassigned to a spectrum of frequencies.Another aspect of invention is providing a non-transitory computer-readable storage medium storing instructions that, when executed by one or more processors, causes the one or more processors to perform operations according to the inventive method.However, while certain embodiments of the present invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention as defined by the following claims.List of reference numbersJRC - Joint Radar CommunicationCom - Communication signal eRSU - Enhanced Road-side UnitV1 , V2, V3 - VehicleNc - Network connectionV2I - Vehicle-to-lnfrastructureV2X - Vehicle-to-EverythingTX - TransceiverRX - ReceiverBibliographic referencesNon-Patent Literature[1] R. S. Thoma, C. Andrich, G. D. Galdo, M. Dobereiner, M. A. Hein, M. Kaske, G. Schafer, S. Schieler, C. Schneider, A. Schwind, and P. Wendland, "Cooperative Passive Coherent Location: A Promising 5G Service to Support Road Safety," IEEE Communications Magazine, vol. 57, no. 9, pp. 86-92, 2019[2] D. Pastina, F. Santi, F. Pieralice, M. Antoniou, and M. Cherniakov, "Passive Radar Imaging of Ship Targets With GNSS Signals of Opportunity," IEEE Transactions on Geoscience and Remote Sensing, pp. 1 -16, 2020[3] S. Bartoletti, A. Conti, and M. Z. Win, "Passive radar via LTE signals of opportunity", in 2014 IEEE International Conference on Communications Workshops (ICC), pp. 181 -185, 2014[4] A. Ali, N. Gonzalez-Prelcic, and A. Ghosh, "Automotive radar radiations as signals of opportunity for millimeter wave V2I links," in 2019 53rd Asilomar Conference on Signals, Systems, and Computers, pp. 554-558, 2019[5] S. Lagen, L. Giupponi, B. Bojovic, A. Demir, and M. Beluri, "Paired Listen before Talk for Multi-RAT Coexistence in Unlicensed mmWave Bands," in 2018 IEEE International Conference on Communications Workshops (ICC Workshops), pp. 1 -6, 2018Patent LiteratureUS 2022094511 A1 KR100813909 B1CN104881995 A

Claims

Patent claims1. Joint radar communication system within a wireless communication environment, comprising at least one processor, at least one transceiver configured to transmit a radar signal by which azimuth data is sent together with radar waveform, at least one receiver configured to receive echoes of the radar signal, and at least one memory communicatively coupled to the at least one processor, characterized in that the transceiver is configured to transmit a joint radar communication signal (JRC), and the receiver is configured to use a joint radar communication channel to receive echoes of the radar signal, and to transmit a communication (JRC) signal.

2. System according to claim ^ characterized in that the joint radar communication signal (JRC) is a radar signal (RCS) carrying data or a communication signal (COM) with radar capabilities.

3. System according to claims 1 and 2, characterized in that in case the transceiver and / or receiver belong to a stationary unit, such as an enhancedroad-side unit (eRSU) with dual-functional radar communication capabilities, the transceiver belonging to the enhanced road-side unit is able to transmit both joint radar communication signal (JRC) and communication signal (COM), and the receiver belonging to the enhanced road-side unit is able to receive and process echoes of the transmitted joint radar communication signal (JRC) and to receive communication signal (COM).

4. System according to claims 1 and 2, characterized in that in case the transceiver and / or the receiver belong to a mobile unit, such as an automotive radar system mounted on a vehicle, the transceiver belonging to the mobile unit is able to transmit both joint radar communication signal (JRC) and communication signal (COM), and the receiver belonging to the mobile unit is able to receive and process the data inserted in the transmitted joint radar communication signal (JRC) and to receive communication signal (COM).

5. System according to claims 1 , 2 and 3, characterized in that the enhanced road-side units are connected in a network, and the network is either a cellular network, a wireless network, a radio-based network, a telephone network, a satellite network, a wired network, a fiber optic network, or a combination thereof.

6. A method of joint radar communication within a wireless communication environment, performed by means of at least one processor, at least one transceiver, at least one receiver, and at least one memory communicatively coupled to the at least one processor, wherein the method comprises(S1 ) at transceiver, transmitting a joint radar communication signal including at least azimuth data together with radar waveform,(52.1) at receiver, direction and identity of the transceiver is obtained from the azimuth data, and radar echoes are reflected, at transceiver, the reflected radar echoes are processed, and radar detection operations based on the reflected echoes are performed, characterized in that(52.2) at receiver, a joint radar communication (JRC) signal is transmitted via a joint radar communication channel.

7. Method of claim 6, characterized in that the joint radar communication signal is either a radar signal (RCS) carrying data or a communication signal (COM) with radar capabilities.

8. Method of claim 7, characterized in that the communication signal also include data about communication channel(s) described by, at least, time- frequency-resources or access parameters, to be used for, at least, beam alignment.

9. Method according to claim 6, characterized in that, in case the transceiver and / or receiver belong to a stationary unit, such as an enhanced roadside unit (eRSU), joint radar communication signal (JRC) and communication signal (COM) are both transmitted by the transceiver belonging to the enhanced road-side unit, and echoes of the transmitted joint radar communication signal (JRC) and toreceive communication signal (COM) are recived and processed by the receiver belonging to the enhanced road-side unit (eRSU).

10. Method of claim 6, characterized in that, in case the transceiver and / or the receiver belong to a mobile unit, such as an automotive radar system mounted on a vehicle, both the joint radar communication signal (JRC) and the communication signal (COM) are transmitted by the transceiver belonging to the mobile unit, and the data inserted in the transmitted joint radar communication signal (JRC) and the communication signal (COM) are received and processed by the receiver belonging to the mobile unit.

11. Method of claim 7, configured as part of data communication service, characterized in that the radar data are spatial, vectorial data transmitted out-of-band through automotive radar signals.

12. Method of claim 7, characterized in that the communication signal sent by receiver are MAC-related information for vehicle-to-infrastructure (V2I), infrastructure-to-vehicle (I2V) or vehicle-to-vehicle (V2V) communication in one shot.

13. Method of claim 6, c h a r a c t e r i z e d in t h a t the communication signal sent by receiver are assigned to a predetermined spectrum or frequencies.

14. Method of claim 6, characterized in that the communication signal sent by receiver is based on a per-service priority token, unassigned to a spectrum or frequencies.

15. A non-transitory computer-readable storage medium storing instructions that, when executed by one or more processors, causes the one or more processors to perform operations according to the method from claims 6 to 14.

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