Adaptive radar for detecting near and far objects

Abstract

A device (201) in a mobile communication system performs radar sensing of an environment by operating in at least one of at least two radar modes, including a monostatic full-duplex long-pulse based radar mode and a monostatic short-pulse based radar mode, wherein a radar pulse (205) transmitted by the device when operating in the monostatic full- duplex long-pulse based radar mode is longer than the radar pulse transmitted by the device when operating in the monostatic short-pulse based radar mode. Mode selection includes operating (903) in the monostatic full-duplex long-pulse based mode when sensing is to be confined to distances smaller than a first distance from the device (901, Yes); and operating (907) in the monostatic short- pulse based radar mode when sensing is to be no closer than a second distance from the device (905, Yes), wherein the second distance is greater than or equal to the first distance.

Description

[0001] ADAPTIVE RADAR FOR DETECTING NEAR AND FAR OBJECTS

[0002] BACKGROUND

[0003] The present invention relates to radar sensing / measurement of objects in an environment, and more particularly to radar sensing / measurement using radio equipment that is capable of sensing / measuring both near and distant objects.

[0004] Some or all of the following abbreviations are used in this specification:

[0005] Abbreviation Explanation

[0006] 3 GPP Third Generation Partnership Project

[0007] FD Full Duplex

[0008] FMCW Frequency Modulated Continuous Wave

[0009] ISAC Integrated Sensing and Communication

[0010] JCAS Joint Communication and Sensing

[0011] LTE Long Term Evolution

[0012] NR New Radio

[0013] OFDM Orthogonal Frequency-Division Multiplexing

[0014] RCS Radar Cross Section

[0015] TDD Time Division Duplex

[0016] In Joint Communication and Sensing (JCAS) or Integrated Sensing and Communication (ISAC), the sensing functionality is integrated into a communication system. Examples of such communication systems include, but are not limited to, LTE, NR, Wi-Fi, and communication systems conforming to any future standard, such as 6G.

[0017] As an example, NR applies an OFDM modulation scheme, so the smallest schedulable time unit is then an OFDM symbol. NR supports different numerologies (subcarrier spacing of OFDM), including among others 15, 30, 60, and 120 kHz. The symbol duration (including a cyclic prefix length) for these numerologies is given in Table 1.

[0018] Table 1 : NR numerologies and associated OFDM symbol duration (incl. cyclic prefix)

[0019] In a monostatic radar device or system, transmitter and receiver nodes are collocated (often in the same node). The transmitter sends a waveform that is reflected by the environment and objects. These reflections are received by the receiver and processed by, for example, the receiver or another connected entity, to obtain information about the environment and / or objects.

[0020] A radar pulse spanning one or multiple OFDM symbols would allow radar functionality to be easily integrated into a communication system. For example, for 30 kHz numerology, the OFDM symbol duration is approximately 36 [is (see Table 1). A radar pulse spanning a single OFDM symbol duration would have the same length. A round trip time of 36 [is corresponds to single-way distance of 5.4 km. For objects closer than 5.4 km, the echo would arrive while the transmitter is still transmitting the radar pulse. This point is illustrated in Figures 1A and IB, with Figure 1A showing the roundtrip path 101 of a transmitted radar pulse, and Figure IB showing the transmitted radar pulse 103 and the relative timing of the pulse's reflection 105. The time difference between the moment of transmission and the moment ofreception is the signal's roundtrip time 107.

[0021] Objects can be located at a variety of distances from the transmitting device, and for some of these the reflection will reach the device while the device is still transmitting. Figure IB illustrates the range 109 of roundtrip times associated with near-distance objects.

[0022] It can be seen that, for near-range objects, the signal's reflection 105 must be received in presence of strong self-interference (i.e., the transmitted signal 103 that leaks into the receiver). Receivers having this capability are often called "full-duplex capable receivers". Full-duplex operation puts high requirements on the receiver and potentially also on the transmitter (e.g., in terms of linearity), especially for high levels of transmit powers, where a high degree of self-interference cancellation is required. One way of avoiding the need for full-duplex capability is by using short radar pulses, configured to have a pulse length shorter than the roundtrip time of the closest object that the equipment is designed to detect. This allows transmission of the pulse to have ended by the time the earliest echo of that pulse arrives back at the device. This is illustrated by Figures 2A and 2B. Figure 2A illustrates a device 201 that transmits a pulse that is reflected back to the device by an object 203. Figure 2B shows relative timings between the transmitted pulse 205 and the received reflection 207. In practical embodiments, the transmission of the pulse 205 is preceded and followed by transients 209 that should also be considered. The pulse duration TPuise together with the transient time Ttrans determines a blind zone or exclusion zone (of size Rmm) around the transmitter inside which echoes are received while the transmitter is still transmitting (or during which transients are not yet sufficiently decayed), making reception difficult if not impossible. Ideally the transmitted pulse would stop abruptly, but in reality, a sufficiently low power level is achieved only after a certain amount of time (the transient time). Reasons for this transient time include, without limitation, hardware-related effects in the power amplifier (both signal path and power supply), switches, or delays due to control signaling.

[0023] The decay time is also influenced by the acceptable level of interference, which depends on the required level of performance. The required decay time is also impacted negatively by the transmitted power level, and positively by the extent of isolation between transmitter and receiver.

[0024] Figure 3 is a collection of graphs showing, for various configurations, the maximum sensing distance (i.e., Rmax) of a monostatic short -pulse based radar as a function of the exclusion zone (i.e., Rmm)- The larger the exclusion zone, the longer the radar pulse can be, which leads to more transmitted energy and thus longer radar ranges. The different curves show the performance for different numbers of pulses transmitted. Related simulation parameters are listed in Table 2.

[0025]

[0026] Table 2: Simulation parameters

[0027] To avoid self-interference, radar operation occupies a "radar gap" between other signaling that the device may perform. The radar gap comprises the pulse transmission followed by a silent interval as illustrated in Figure 4. Other signaling (e.g., transmissions of communication signals, or even other radar signals) takes place outside of the radar gap. Without the silent interval, transmissions within this time duration would overlap with reception of echoes leading to self-interference. The duration of this silent interval, Tint, is, to the largest extent, determined by the maximum radar range Rmaxand the transient time duration, according to: where Co is the speed of light. The total duration of pulse and silent interval (assuming same transient times for on-off and off-on signal transitions) then becomes: = 4 [is. If late reflections from very distant objects arriving after transmission of a later (e.g., next) radar pulse are a problem, the silent interval could be extended, and different radar pulse sequences can be used for the different pulses, so reflections from one can be distinguished from reflections of the other.

[0028] The inventors have ascertained that conventional technology brings with it a number of problems. For example, full-duplex capability complicates a transceiver, especially for high-power nodes (e.g., base station equipment used in cellular communications).

[0029] A monostatic short-pulse based radar deployment as discussed above avoids the need for full-duplex capability, but has an exclusion zone, so only objects situated outside this exclusion zone can be detected (i.e., this type of radar is blind to close objects). The exclusion zone can be reduced, but this conies at the expense of hardware capable of supporting fast transient times.

[0030] Existing radar systems are purpose-built and can thus be designed to use a single radar technology to cover the desired range of distances to objects. This is enabled by, for example, dedicated hardware, antenna setups optimized for radar, and the like. But when radar functionality is to be integrated into a mobile communication network, the hardware requirements are to the largest extent set by considerations related to communication, not radar, and this makes it difficult if not impossible to cover the desired range based on a single radar technology. A dedicated radar solution also has an advantage in being able to use a waveform optimized for radar operation (e.g., frequency-modulated continuous-wave (FMCW)), whereas a radar system integrated into a mobile communication system needs to use a waveform that can be generated within the framework of the communication system.

[0031] There is therefore a need for a technology that solves the above and / or related problems associated with the use of radio communication equipment for monostatic radar sensing.

[0032] SUMMARY

[0033] It should be emphasized that the terms "comprises" and "comprising", when used in this specification, are taken to specify the presence of stated features, integers, steps or components; but the use of these terms does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0034] Moreover, reference letters may be provided in some instances (e.g., in the claims and summary) to facilitate identification of various steps and / or elements. However, the use of reference letters is not intended to impute or suggest that the so-referenced steps and / or elements are to be performed or operated in any particular order.

[0035] In accordance with one aspect of the present invention, the foregoing and other objects are achieved in technology (e.g., methods, apparatuses, nontransitory computer readable storage media, program means) that enables a device in a mobile communication system to perform radar sensing of an environment. In an aspect of some but not necessarily all embodiments consistent with the invention, this comprises selectively operating the device in at least one of at least two radar modes, wherein the at least two radar modes comprise a monostatic full-duplex long -pulse based radar mode and a monostatic short-pulse based radar mode, wherein a radar pulse transmitted by the device when operating in the monostatic full- duplex long-pulse based radar mode is longer than the radar pulse transmitted by the device when operating in the monostatic short-pulse based radar mode. Selectively operating the device in said at least one of the at least two radar modes comprises operating the device in the monostatic full-duplex long-pulse based mode when sensing is to be confined to distances smaller than a first distance from the device; and operating the device in the monostatic shortpulse based radar mode when sensing is to be no closer than a second distance from the device, wherein the second distance is greater than or equal to the first distance.

[0036] In another aspect of some but not necessarily all embodiments consistent with the invention, the device decides which of the at least two radar modes is to be used by assessing one or more criteria.

[0037] In yet another aspect of some but not necessarily all embodiments consistent with the invention, the second distance is equal to the first distance. In some alternative embodiments, the second distance is greater than the first distance.

[0038] In still another aspect of some but not necessarily all embodiments consistent with the invention, the first distance is a minimum sensing distance of the monostatic short-pulse based radar mode.

[0039] In another aspect of some but not necessarily all embodiments consistent with the invention, the second distance is a maximum sensing distance of the monostatic full-duplex long-pulse based mode.

[0040] In yet another aspect of some but not necessarily all embodiments consistent with the invention, when the second distance is greater than the first distance, and when the first distance is a minimum sensing distance of the monostatic short-pulse based radar mode and the second distance is a maximum sensing distance of the monostatic full-duplex long-pulse based radar mode, the technology scans a region that spans distances between the first distance and the second distance by operating the device in the monostatic full-duplex long- pulse based mode and also operating the device in the monostatic short-pulse based radar mode. The technology further uses, as sensing data of the region, sensing data collected by operating the device in the monostatic full-duplex long-pulse based mode in combination with sensing data collected by operating the device in the monostatic short-pulse based radar mode.

[0041] In still another aspect of some but not necessarily all embodiments consistent with the invention, the monostatic full-duplex long-pulse based mode comprises using a first transmission power level when transmitting the radar pulse; the monostatic short-pulse based radar mode comprises using a second transmission power level when transmitting the radar pulse; and the second transmission power level is greater than the first transmission power level.

[0042] In another aspect of some but not necessarily all embodiments consistent with the invention, the technology obtains, from an application running on the device, range information pertaining to an area to be sensed.

[0043] In yet another aspect of some but not necessarily all embodiments consistent with the invention, range information pertaining to an area to be sensed is obtained from another device.

[0044] In some but not necessarily all alternative embodiments, range information pertaining to an area to be sensed is obtained from another device.

[0045] In still another aspect of some but not necessarily all embodiments consistent with the invention, an object to be found has a radar cross section, RCS; and the technology uses the RCS while scanning for the object. In some alternatives, a maximum sensing distance of the monostatic full-duplex long-pulse based mode is determined based at least in part on the RCS of the object to be found while scanning. And in some further alternatives, a minimum sensing distance of the monostatic short -pulse based radar mode is determined based at least in part on the RCS of the object to be found while scanning.

[0046] In another aspect of some but not necessarily all embodiments consistent with the invention, a maximum sensing distance of the monostatic full-duplex long -pulse based mode is determined based at least in part on a speed of a target to be sensed. And in some further alternatives, a minimum sensing distance of the monostatic short-pulse based radar mode is determined based at least in part on a speed of an object to be sensed.

[0047] In yet another aspect of some but not necessarily all embodiments consistent with the invention, the device comprises a first transceiver and a second transceiver; and the first transceiver is operated in the monostatic full-duplex long -pulse based mode to sense the distances smaller than the first distance while the second transceiver is operated in the monostatic short-pulse based radar mode to sense distances no closer than the second distance.

[0048] In still another aspect of some but not necessarily all embodiments consistent with the invention, operating the device in the monostatic full-duplex long-pulse based mode comprises tilting a transmission of a radar pulse downward towards an area to be sensed.

[0049] In another aspect of some but not necessarily all embodiments consistent with the invention, the technology coordinates with a second device such that a radar pulse transmission from the device will not occur concurrently with a radar pulse transmission from the second device.

[0050] In yet another aspect of some but not necessarily all embodiments consistent with the invention, the technology coordinates with a second device such that, when the device is operated in the monostatic full -duplex long -pulse based mode, the second device is operated in the monostatic short-pulse based radar mode.

[0051] In still another aspect of some but not necessarily all embodiments consistent with the invention, the device comprises an antenna panel that comprises a plurality of antenna elements.

[0052] In another aspect of some but not necessarily all embodiments consistent with the invention, the monostatic full-duplex long -pulse based mode comprises using a first grouping of one or more of the antenna elements for transmission and a second grouping of one or more of the antenna elements for reception.

[0053] In yet another aspect of some but not necessarily all embodiments consistent with the invention, the monostatic short-pulse based mode comprises using a third grouping of the antenna elements for transmission when scanning a first span of distances, and using a fourth grouping of the antenna elements for transmission when scanning a second span of distances. In such embodiments, the first span of distances is closer to the device than the second span of distances, and the fourth grouping of antenna elements comprises more antenna elements than the third grouping of antenna elements.

[0054] In still another aspect of some but not necessarily all embodiments consistent with the invention, the device is a node in a telecommunications system.

[0055] In another aspect of some but not necessarily all embodiments consistent with the invention, the device is a User Equipment for use in a telecommunications system.

[0056] BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The objects and advantages of the invention will be understood by reading the following detailed description in conjunction with the drawings in which:

[0058] Figure 1A shows a roundtrip path of a transmitted radar pulse.

[0059] Figure IB shows a transmitted radar pulse and the relative timing of the pulse's reflection.

[0060] Figure 2A illustrates a device that transmits a pulse that is reflected back to the device by an object. Figure 2B shows relative timings between a transmitted pulse and its received reflection.

[0061] Figure 3 is a collection of graphs showing, for various configurations, the maximum sensing distance of a monostatic short-pulse based radar as a function of the exclusion zone.

[0062] Figure 4 illustrates a pulse transmission followed by a silent interval, together forming a radar gap.

[0063] Figure 5 A schematically illustrates effective values of Rmi„ and Rmaxfor sensing high speed objects and / or objects having a small RCS.

[0064] Figure 5B schematically illustrates effective values of Rmi„ and Rmaxfor sensing low speed objects and / or objects having a large RCS.

[0065] Figure 6 shows placements of a device (Rang ), placement of Rmi„ for the monostatic short-pulse based radar mode, and a placement for the monostatic full-duplex based radar mode's Rmax.

[0066] Figures 7A is, in one respect, a flowchart of actions performed by a device as part of a monostatic radar operation in accordance with some but not necessarily all inventive embodiments.

[0067] Figures 7B is, in one respect, a flowchart of actions performed by a device as part of a monostatic radar operation in accordance with some but not necessarily all alternative inventive embodiments.

[0068] Figures 7C is, in one respect, a flowchart of actions performed by a device as part of a monostatic radar operation in accordance with some but not necessarily all additional alternative inventive embodiments.

[0069] Figures 8A, 8B, and 8C each show a different use configmation of an antenna panel comprising a plurality of antenna elements serving the frequency assigned for radar sensing.

[0070] Figure 9 is, in one respect, a flowchart of actions performed by a device as part of a monostatic radar operation in accordance with some but not necessarily all inventive embodiments.

[0071] Figure 10 shows an exemplary controller that may be included in a device having radar signal transmitting and receiving capabilities to cause any and / or all of the herein- described and illustrated actions associated with that device to be performed. DETAILED DESCRIPTION

[0072] The various features of the invention will now be described with reference to the figures, in which like parts are identified with the same reference characters.

[0073] The various aspects of the invention will now be described in greater detail in connection with a number of exemplary embodiments. To facilitate an understanding of the invention, many aspects of the invention are described in terms of sequences of actions to be performed by elements of a computer system or other hardware capable of executing programmed instructions. It will be recognized that in each of the embodiments, the various actions could be performed by specialized circuits (e.g., analog and / or discrete logic gates interconnected to perform a specialized function), by one or more processors programmed with a suitable set of instructions, or by a combination of both. The term "circuitry configured to" perform one or more described actions is used herein to refer to any such embodiment (i.e., one or more specialized circuits alone, one or more programmed processors, or any combination of these). Moreover, the invention can additionally be considered to be embodied entirely within any form of non-transitory computer readable carrier, such as solid-state memory, magnetic disk, or optical disk containing an appropriate set of computer instructions that would cause a processor to carry out the techniques described herein. Thus, the various aspects of the invention may be embodied in many different forms, and all such forms are contemplated to be within the scope of the invention. For each of the various aspects of the invention, any such form of embodiments as described above may be referred to herein as "logic configured to" perform a described action, or alternatively as "logic that" performs a described action.

[0074] As mentioned earlier, the inventors have recognized that integrating radar functionality into a communications device (e.g., network node such as a base station or equivalent; or user equipment in a mobile communication system) presents challenges because the hardware considerations are mostly decided based on communication rather than radar applications, and incorporating any one solution (e.g., full-duplex radar operation or short-pulse based radar) is not adequate for sensing a range of distances spanning from near to far.

[0075] The inventors have, after consideration of problems presented and using inventive skill, recognized that full-duplex capability is easier to realize for low- and medium transmit power because the power that leaks into the received signal is lower and thus less selfinterference cancellation is needed. Accordingly, in an aspect of embodiments consistent with the invention, a radar functionality deployed in a communication device applies a monostatic radar requiring full -duplex capability for small distances. This is in recognition that for short- range radar, the path loss is lower, hence lower transmission power is needed to reach an object, and lower receiver sensitivity is needed to receive a reflected signal. Thus, simpler self-interference cancellation is sufficient.

[0076] In another aspect of embodiments consistent with the invention, the radar functionality when applied for larger distances is realized using a monostatic short-pulse based radar system. Such a system is blind / low-performing for short range within its exclusion zone but can detect objects outside the exclusion zone. Outside the exclusion zone no self-interference from the device's own transmitted signal occurs (since the transmission already stopped when receiving starts). Therefore, higher transmission power levels required to sense larger distances can be used, and the receiver sensitivity can be high.

[0077] In another aspect of some but not necessarily all embodiments, the use of one technology or the other is decided based on a sensing distance or range of distances to be explored. If this is unknown initially, then in another aspect of some but not necessarily all embodiments, an initial detection phase can be invoked in which both radar systems are used in succession and - if an object is detected - a second phase of sensing is then used that utilizes that radar system deemed appropriate for the detected object. Radar cross section and velocities of objects of interest may change the threshold that decides when to switch between radar modes.

[0078] If the radar range is dynamically configmed, that range will determine which radar system to use.

[0079] These and further aspects of embodiments consistent with the invention are now described in further detail.

[0080] As mentioned above, inventive embodiments selectively utilize, based at least on distance to be sensed, one of several different types of radar technologies. When the system is to sense within regions having a range of distances considered by the designers to be short- range, it applies a monostatic full-duplex based radar approach. One reason for this is that less transmit power is needed for short radar ranges, and this simplifies full-duplex operation (e.g., self-interference cancellation is less complex). For the limited RF isolation needed, different parts of a multi-antenna array antenna panel can be used for both transmission of radar pulses and reception of their reflections (echoes).

[0081] But when larger distances are to be sensed, higher transmission powers are required and the device therefore selects operation in a monostatic short-pulse based radar mode. In this case, the higher transmission power is not a problem because no self-interference (i.e., from the device's own transmitted radar signal) occurs because the transmission will already be completed when even the earliest possible echo signal from outside the exclusion zone arrives. The receiver can then operate with high sensitivity.

[0082] It is noted that relative terms "short" and "long" have been used to describe different radar ranges. It is noted that what constitutes "short" or "long" can differ from one embodiment to the next, and is up to the designers of the system. However, in all instances, "short" distances are closer to the device than "long" distances.

[0083] Selection of which radar mode to use at any given time is based on criteria, including the range to be sensed, and this is discussed in further detail in the following. Generally, for small (short) distances, full-duplex based monostatic radar is used and for larger distances, short-pulse based monostatic radar. When implemented in a communication system such as one employing OFDM technology, allocation of spectral resources includes a time component defined as slots. It is therefore convenient to transmit a radar pulse in one or more time slots of such a system. However many such slots are allocated for use as pulses, for any one embodiment the length of a radar pulse in the monostatic full-duplex based radar mode is longer than the length of a radar pulse in the monostatic short-pulse based radar mode.

[0084] In some but not necessarily all embodiments, a device may perform a detection phase of operation followed by a second, more detailed scan or tracking phase. These different phases may use different radar modes: In the detection phase, the radar needs to scan the complete range. Nearer distances, including areas within the exclusion zone of the short -pulse based monostatic radar are sensed using the full-duplex based monostatic radar, whereas areas outside the exclusion zone are sensed using the short-pulse based monostatic radar. The order in which these separate sensing operations is performed is not an essential aspect of the invention, and any order or even in some embodiments concurrent sensing of both ranges are contemplated. In some but not necessarily all embodiments when concurrent sensing of both ranges is performed, different center frequencies can be used for the respective radar pulses to allow them to operate at the same time.

[0085] If an object is detected in the first phase, a second phase is activated. The second phase can be, for example, a tracking phase (i.e., to follow the detected object) or just a more capable radar signal with, for example, better range or angular resolution. Depending at which range the object has been detected, this second phase should use that radar mode best suited for this distance. In some but not necessarily all embodiments, a device is configmed to sense a particular area, and in such cases the distance from the device to this area determines the radar mode. If the area is large so as to span both "short" and "long" distances, the device may need to use both radar modes to acquire information about objects in the near and far areas. The configuration of what area to sense can, for example, come from an application running directly on the device or it may be received from a second / other node or device.

[0086] In another aspect of some but not necessarily all embodiments, the amount of time spent in each radar mode may be equal or different. For example, a radar application may require that more frequent radar updates be performed in a particular region, while the radar operation in another region may have less stringent updating requirements. For certain applications, targets in the near region (i.e., closer to the radar-capable device) with higher velocity might have a need to be monitored more frequently if the purpose is to avoid collisions; in other applications, it could be a defined specific area where monitoring of objects is more critical (e.g., dependent on a relation and relative velocity between nearby objects in such region).

[0087] For small exclusion zones, the target area outside the exclusion zone might be larger than the area of the exclusion zone which could require more time spent in sensing the radar area outside the exclusion zone.

[0088] In another aspect of some but not necessarily all embodiments, RCS and target velocity can impact the distance at which the switch between the two radar modes occurs. The distance at which switching from one mode to another is made can be further optimized by further including an object's properties (e.g., RCS, velocity) as one or more of the criteria (in addition to distance) that are assessed to decide in which radar mode to operate. If, in addition to the target area, properties of the targeted object (e.g., its RCS, velocity) are also configmed, this information can be used to optimize the switching distance.

[0089] The monostatic full-duplex based radar has an upper range limit, Rmax, that depends on the transmit power and receive sensitivity when the device's transceiver is operated in full duplex mode. Depending on the RCS of the targeted object, given a constant transmit power and receive sensitivity, Rmaxvaries in relation to RCS, with larger values of RCS leading to larger Rmaxvalues, and lower RCS leading to a smaller RmaxSo, for example, when the radar application requires scanning only for objects with large RCS, a given transmit power and receive sensitivity gives a larger Rmax(i.e. monostatic full-duplex based radar can be used for a longer range). An effect of a larger Rmaxis that Rmi„ of the monostatic short-pulse based radar is can then also be increased, if desired, since the operating region of the monostatic full-duplex radar is increased. Increasing Rmi„ enables longer pulses to be configured, thereby increasing radar range of the monostatic short -pulse based radar mode. Depending on the RCS of the targeted object(s), the border between monostatic full-duplex based radar and monostatic short-pulse based radar changes; this feature can be used to dynamically increase coverage for radar applications that assume a large RCS for the objects of interest.

[0090] Similarly in another aspect of some but not necessarily all embodiments, the border for Rmaxcould depend on the maximum speed of the object(s) to be detected. Stationary or slow-moving objects can benefit from longer receiver integration times and achieve higher processing gain compared to fast-moving objects and hence allow for larger Rmaxwhich in turn allows for an increased RmlnThis enables the use of longer pulses for the short-pulse radar and thereby larger total radar range.

[0091] The above discussion demonstrates that embodiments can optimize radar system operation by tuning the effective Rmaxand Rmi„ values in dependence on the intended radar use case. This tuning can be done dynamically over time within a system and / or between systems operating in different environments with different use case requirements. Figures 5A and 5B illustrates this point, with Figure 5 A schematically illustrating effective values of Rmi„ and Rmaxfor sensing high speed objects and / or objects having a small RCS, and Figure 5B schematically illustrating effective values of Rmi„ and Rmaxfor sensing low speed objects and / or objects having a large RCS. Tuning the threshold distance is especially important if only one or relatively few velocity hypotheses are checked in the correlation. If multiple hypotheses are checked, this is less important, since then longer integration times are also possible for fast moving objects.

[0092] To avoid having a range that can neither be sensed by the monostatic full-duplex based radar mode nor the monostatic short-pulse based radar mode, the maximum range of the monostatic full-duplex based radar (Rmax) should not be smaller than the size of the exclusion zone of the monostatic short-pulse based radar mode (Rm,„). An acceptable arrangement is illustrated in Figure 6, which shows placements of the device (Rongm), placement of Rmi„ for the monostatic short-pulse based radar mode (in the figure, labeled as Rshort -pulse min )> and a placement for the monostatic full-duplex based radar mode's Rmax(in the figure, labeled as "RFDjong_pUie_max").

[0093] For sensing objects in a first region 601 lying from up to Rshort _puise_mm, the monostatic full-duplex long-pulse based mode should be used. And for sensing objects in a third region 605 no closer to the device than RFDjong_puise _max, the monostatic short-pulse based mode should be used. Also illustrated in Figure 6 is an intermediate, second region 603 lying between This second region 603 exists when , and in this case there are alternative embodiments:

[0094] - some in which the second region 603 is sensed exclusively using the monostatic full- duplex long-pulse mode;

[0095] - some in which a border is defined somewhere within the second region 603 (e.g., half-way between the limits of the second region 603), wherein one mode is used for sensing closer than the border and the other mode is used for sensing farther away;

[0096] - some in which the second region 603 is sensed exclusively using the monostatic short-pulse mode; and

[0097] - some in which the second region 603 is sensed using both the monostatic full-duplex long-pulse mode and the monostatic short-pulse mode, with data collected from both sensing modes being used in combination to produce a final radar image.

[0098] In the case in which both modes of radar operation are used to sense the second region 603, both radar modes work on their respective range limits with potentially worse performance. Full-duplex based monostatic radar needs to transmit with high power which is at the limit of what the transceiver can sufficiently cancel. The signal to noise ratio of the received signal is then on the limit for object detectability. Short-pulse based monostatic radar, on the other hand, needs to receive echoes just after the end of the exclusion zone, so likely transients from the transmitted pulse and transmitter noise are not yet fully decayed and stronger self-interference occurs. However, combining the sensing results from the two modes can compensate for the reduced performance.

[0099] It will be recognized that in some embodiments, , and in this case there are essentially only two regions, that is, the first region 601 and the third region 603. Sensing of these regions is performed as described above.

[0100] Further aspects of embodiments consistent with the invention are now discussed with reference to Figures 7A, 7B, and 7C, each of which is, in one respect, a flowchart of actions performed by a device (e.g., base station, network node, user equipment, etc.) as part of a monostatic radar operation in accordance with some but not necessarily all inventive embodiments. In other respects, the blocks depicted in each of Figures 7A, 7B, and 7C can also be considered to represent means 700, 710, 720 (e.g., hardwired or programmable circuitry or other processing means) for carrying out the described actions. One class of exemplary embodiments is illustrated in Figure 7A. Here, the range of an area to be scanned is compared with a maximum range, Rmax, that can be scanned using the monostatic full-duplex long-pulse mode of radar operation (decision block 701). If the range of the area to be scanned is less than Rmax("Yes" path out of decision block 701), then the monostatic full-duplex long-pulse mode of radar operation is selected for use during the scanning (step 703). It will be observed that, in this case, the second range 603 as shown in Figure 6 (the "intermediate" range) will be scanned using the monostatic full-duplex long- pulse mode of radar operation. But for other ranges to be scanned ("No" path out of decision block 701), the monostatic short-pulse mode of radar operation is selected for use during the scanning (step 705).

[0101] In another class of alternative embodiments, as shown in Figure 7B, the range of an area to be scanned is compared with a minimum range,m,„, that can be scanned using the monostatic short-pulse mode of radar operation (decision block 711). If the range of the area to be scanned is greater than Rmi„ ("Yes" path out of decision block 711), then the monostatic short-pulse mode of radar operation is selected for use during the scanning (step 713). It will be observed that, in this case, the second range 603 as shown in Figure 6 (the "intermediate" range) will be scanned using the monostatic short-pulse mode of radar operation. But for other ranges to be scanned ("No" path out of decision block 711), the monostatic full-duplex long -pulse mode of radar operation is selected for use during the scanning (step 715). in yet another class of alternative embodiments, as shown in Figure 7C, the range of an area to be scanned is compared first with a minimum range, Rmi„, that can be scanned using the monostatic short-pulse mode of radar operation (decision block 721). If the range of the area to be scanned is less than Rmi„ (" Y es" path out of decision block 721), then the range corresponds to the first range 601 illustrated in Figure 6, and the monostatic full-duplex long- pulse mode of radar operation is selected for use during the scanning (step 723).

[0102] If the range of the area to be scanned is not less than Rmi„ ("No" path out of decision block 721), then another comparison is made (decision block 725) to detect whether the range of the area to be scanned is less than Rmax. If it is not ("No" path out of decision block 725), then the range corresponds to the third range 605 illustrated in Figure 6, and the monostatic short-pulse mode of radar operation is selected for use during the scanning (step 727).

[0103] But if the range of the area to be scanned is less than Rmax, ("Yes" path out of decision block 725), this corresponds to the second range 603 shown in Figure 6 (the "intermediate" range), both the monostatic full-duplex long-pulse mode of radar operation and the monostatic short -pulse modes of radar operation are selected for performance (step 729). Scanning information obtained from these two different types of scans can then be combined to produce an improved image of anything detected in the second range 603.

[0104] It can be seen from a comparison of the embodiments illustrated in Figures 7 A, 7B, and 7C that all three embodiments lead to the same operation for instances in which Rmax= Rmin However, different behavior is obtained when Rmin< Rmax(i.e., when there is a second region 603 as illustrated in Figure 6).

[0105] In further aspects, it is noted that embodiments consistent with the invention can advantageously operate both radar modes to cover the complete target area (assuming the complete target area stretches from below of monostatic short-pulse radar mode and exceeds beyond Rmaxof monostatic full -duplex long -pulse radar mode). Since a given transmitter can at any time be in only one of the radar modes, monostatic full-duplex long- pulse based radar mode and monostatic short -pulse based radar mode are multiplexed in time. However, some equipment having multiple transmitters (e.g., a base station in a telecommunications system) may simultaneously operate in monostatic full-duplex long- pulse based radar mode in one set of transmitters and on another set (of different) transmitters monostatic short-pulse based radar mode, if interference between received echo signals from different transmitters and cancellation of transmitter to receiver leakage allows for this operation.

[0106] It is also beneficial when designing a system to take into account interference between nearby radar devices. One possibility for improving the interference situation between neighboring devices (e.g., base stations) is to coordinate which radar mode is used in which device. If, for example, a first device such as a base station mounted at an elevated position uses monostatic full-duplex long-pulse based radar (i.e., for short range sensing), it can tilt its transmission beams downward to focus transmission on the near area and cause less interference in a farther away region. At the same time a second device (e.g., second base station) could do the same, also using monostatic full-duplex long-pulse based radar to scan an area close to the second device. When both devices want to scan a farther away region, they can be configured to use different time slots to avoid interfering with one another. Depending on deployment, performance requirement, and interference, it might be possible to arrange for one device to scan a far region (using monostatic short-pulse based radar mode) while the other device scans the near region (down-tilt, monostatic full-duplex long-pulse based radar). And in any embodiments, it is also possible for the devices to improve the interference situation by using different center frequencies for their radar pulses. Still further aspects of some but not necessarily all embodiments will now be discussed with reference to Figures 8A, 8B, and 8C, which each show a different use configmation of an antenna panel 801,803,805 comprising a plurality of antenna elements serving the frequency assigned for radar sensing. As illustrated in Figure 8A, an antenna panel 801 can be configmed such that some elements are chosen for reception and some for transmission during full duplex operation. The receive and transmit antenna elements can be part of the same antenna panel or different antenna panels. When using the same panel, it must therefore have the possibility to configure part of it in receive mode and part in transmit. For instance, the panel can be split into two halves, like upper half for receiving and lower half for transmission, or vice versa. In some but not necessarily all embodiments, such as is illustrated in Figure 8A, there can also be some unused rows between receive elements and transmit elements for improving isolation between them. The array can of comse also be split along columns, or in other configmations as well.

[0107] During full duplex operation, due to limited isolation, especially when using the same panel, the receiver must be set in a low gain mode, providing high linearity at the cost of degraded noise performance. It may be that settings with lower gain must be designed into the equipment, even lower than me typically used when the equipment is used for communication. This extends the input power range of the receiver. It may also be that the power control range of the transmitter must be extended to lower output power.

[0108] During pulsed operation, all antenna elements can be used in a panel, altematingly for reception and transmission. Figure 8B illustrates a configuration 803 in which all antenna elements me configmed for transmission, and Figure 8C illustrates a configuration 805 in which all antenna elements me configmed for reception. The transmit / receive switch, connecting each antenna element to either receiver or transmitter, must then be fast enough not to significantly degrade the exclusion zone by requiring a long time to make the transition or by having poor timing accmacy in the switch control signal. A design for fast and accurate switching speed can then be used, which may require a modification compmed to a radio node designed for communication purposes only. Even without such a modification, however, it is possible to improve the performance, by using two different pulsed radm modes (i.e. , two different modes each operating in monostatic short-pulse radm mode). The first of these modes would then use different antenna elements for reception and transmission, as in the full duplex long-pulse mode but without operating the receiver and transmitter simultaneously, so that a fast transmit / receive switch is not needed. The second of these short-pulse modes would then use all antenna elements, with the shortcomings of the slow switches coming into play to switch between transmission and reception. This second short-pulse mode can then be used for long distances, where the switching speed is less important, and the first short -pulse mode for intermediate distances, between the full duplex long-pulse mode and the long-distance shott-pulse mode. The antenna lobes will become narrower when using all antennas, which is most important at long distance, and using all antenna elements provides a maximum antenna gain and output power.

[0109] Still further aspects of some but not necessarily all inventive embodiments will now be described with reference to Figure 9, which in one respect is a flowchart of actions performed by a device (e.g., base station, network node, user equipment, etc.) as part of a monostatic radar operation in accordance with some but not necessarily all inventive embodiments. In other respects, the blocks depicted in Figure 9 can also be considered to represent means 900 (e.g., hardwired or programmable circuitry or other processing means) for carrying out the described actions.

[0110] As shown beginning in Figure 9, the process includes a device in a mobile communication system performing radar sensing of an environment by selectively operating in at least one of at least two radar modes, wherein the at least two radar modes comprise a monostatic full-duplex long -pulse based radar mode and a monostatic short-pulse based radar mode, wherein a radar pulse transmitted by the device when operating in the monostatie full- duplex long-pulse based radar mode is longer than the radar pulse transmitted by the device when operating in the monostatic short-pulse based radar mode. Selection of operational mode includes the device deciding whether sensing is confined within a first range (decision block 901). If so ("Yes" path out of decision block 901), then the device selects to operate in monostatic full-duplex long-pulse based mode (step 903).

[0111] But if sensing is not confined within the first range ("No" path out of decision block 901), then the device decides whether sensing is to cover an area no closer than a second range (decision block 905). The second range may be greater than or equal to the first range. If sensing is to cover an area no closer than a second range ("Yes" path out of decision block 905), then the device selects to operate in monostatic short-pulse based mode (step 907).

[0112] In remaining sensing possibilities ("No" path out of decision block 905), sensing of an intermediate region (e.g., the second region 603 of Figure 6) is to be performed, and as described earlier, different alternative embodiments can take different approaches. In one class of embodiments, the region is sensed by the device selecting to operate in monostatic full-duplex long-pulse based radar mode (step 909). In another class of alternative embodiments, the region is sensed by the device selecting to operate in monostatic short- pulse based radar mode (step 911). And in still another class of alternative embodiments, the region is sensed by the device selecting to operate in each of the monostatic full-duplex long- pulse based radar mode and in the monostatic short-pulse based radar mode (step 913). In this last embodiment, sensing results from both modes can be combined to produce an improved radar image of the sensed area.

[0113] Further aspects of embodiments consistent with the invention will now be described with reference to Figure 10, which shows an exemplary controller 1001 that may be included in a device having radar signal transmitting and receiving capabilities in order to cause any and / or all of the herein-described and illustrated actions associated with that device to be performed. In particular, the controller 1001 includes circuitry configmed to carry out any one or any combination of the various functions described herein. Such circuitry could, for example, be entirely hard-wired circuitry (e.g., one or more Application Specific Integrated Circuits -"ASICs"). Depicted in the exemplary embodiment of Figure 10, however, is programmable circuitry, comprising a processor 1003 coupled to one or more memory devices 1005 (e.g., Random Access Memory, Magnetic Disc Drives, Optical Disk Drives, Read Only Memory, etc.) and to an interface 1007 that enables bidirectional communication with other elements of a device as described above. A complete list of possible other elements is beyond the scope of this description.

[0114] The memory device(s) 1005 store program means 1009 (e.g., a set of processor instructions) configured to cause the processor 1003 to control other device elements so as to carry out any of the aspects described herein. The memory device(s) 1005 may also store data (not shown) representing various constant and variable parameters as may be needed by the processor 1003 and / or as may be generated when carrying out its functions such as those specified by the program means 1009.

[0115] The various embodiments according to the invention are characterized by a number of advantages over prior technologies. These include the ability to have a device in a mobile communications system that is able to perform monostatic radar operation in short (nearby) range and beyond but at the same time avoiding the need for full-duplex operation at high transmission power levels.

[0116] Another advantage over conventional technology is that the herein-described functionality can be obtained at the expense of very limited modifications to existing communication equipment. Such modifications include, in some but not necessarily all embodiments, the ability to control part of an antenna panel for receiving and part for transmission, to support low enough transmit power, and to have receiver gain settings for low sensitivity and high linearity.

[0117] The invention has been described with reference to particular embodiments. However, it will be readily apparent to those skilled in the art that it is possible to embody the invention in specific forms other than those of the embodiment described above.

[0118] For example, in some instances embodiments have been described with reference to the use of a base station as the radar node. However, this is not an essential aspect of inventive embodiments. To the contrary, the various principles and aspects described herein are equally applicable to other communication devices, such as but not limited to a UE. In fact, due to its small dimensions, a UE suffers even more from insufficient antenna isolation between receiver and transmitter, limiting the power (and thus range) in the full-duplex based monostatic radar mode, and this makes the possibility of switching between two radar modes as described herein very attractive.

[0119] Thus, the described embodiments are merely illustrative and should not be considered restrictive in any way. The scope of the invention is further illustrated by the appended claims, rather than only by the preceding description, and all variations and equivalents which fall within the range of the claims are intended to be embraced therein.

Claims

CLAIMS:

1. A method of performing radar sensing of an environment by a device (201, 1001) in a mobile communication system, the method comprising: selectively operating (701, 711, 721, 725, 901) the device (201, 900, 910, 920, 1001) in at least one of at least two radar modes, wherein the at least two radar modes comprise a monostatic full-duplex long-pulse based radar mode (703, 715,723,903,909,913) and a monostatic short-pulse based radar mode (705, 713, 727, 907, 911, 913), wherein a radar pulse (103,205) transmitted by the device (201,900,910,920, 1001) when operating in the monostatic full-duplex long-pulse based radar mode (703, 715,723,903,909,913) is longer than the radar pulse (103,205) transmitted by the device (201,900,910,920, 1001) when operating in the monostatic short-pulse based radar mode (705, 713,727,907, 911, 913), and wherein selectively operating (701, 711, 721, 725) the device (201,900,910,920, 1001) in said at least one of the at least two radar modes comprises: operating the device (201, 900, 910, 920, 1001) in the monostatic full-duplex long- pulse based radar mode when sensing is to be confined to distances smaller than a first distance from the device (201, 900, 910, 920, 1001); and operating the device (201,900,910,920, 1001) in the monostatic short-pulse based radar mode (705, 713, 727, 907, 911, 913) when sensing is to be no closer than a second distance from the device (201,900,910,920, 1001), wherein the second distance is greater than or equal to the first distance.

2. The method of claim 1, comprising: the device (201, 900, 910, 920, 1001) deciding which of the at least two radar modes is to be used by assessing one or more criteria.

3. The method of any one of the previous claims, wherein the second distance is equal to the first distance.

4. The method of any one of claims 1 through 2, wherein the second distance is greater than the first distance.

5. The method of any one of the previous claims, wherein the first distance is a minimum sensing distance of the monostatic short-pulse based radar mode (705, 713, 727, 907,911,913).

6. The method of any one of the previous claims, wherein the second distance is a maximum sensing distance of the monostatic full-duplex long -pulse based radar mode.

7. The method of claim 4, wherein: the first distance is a minimum sensing distance of the monostatic short-pulse based radar mode (705,713,727,907,911,913); the second distance is a maximum sensing distance of the monostatic full-duplex long-pulse based radar mode (703, 715,723,903,909,913); and the method comprises: scanning a region that spans distances between the first distance and the second distance by operating (729,913) the device (201,900,910,920, 1001) in the monostatic full- duplex long-pulse based rad ar mode and also operating (729,913) the device (201,900,910,920, 1001) in the monostatic short-pulse based radar mode (705, 713,727,907, 911, 913); and using, as sensing data of the region, sensing data collected by operating (729, 913) the device (201,900,910,920, 1001) in the monostatic full-duplex long-pulse based radar mode in combination with sensing data collected by operating (729,913) the device (201,900,910, 920, 1001) in the monostatic short-pulse based radar mode (705, 713,727,907,911,913).

8. The method of any one of the previous claims, wherein: the monostatic full-duplex long-pulse based radar mode comprises using a first transmission power level when transmitting the radar pulse (103, 205); the monostatic short-pulse based radar mode (705, 713, 727, 907, 911, 9 13) comprises using a second transmission power level when transmitting the radar pulse (103, 205); and the second transmission power level is greater than the first transmission power level.

9. The method of any one of the previous claims, comprising: obtaining, from an application running on the device (201,900,910,920,1001), range information pertaining to an area to be sensed.

10. The method of any one of claims 1 through 8, comprising: obtaining, from another device (201, 900, 910, 920, 1001), range information pertaining to an area to be sensed.

11. The method of any one of the previous claims, wherein: an object to be found has a radar cross section, RCS; and the method comprises using the RCS while scanning for the object.

12. The method of claim 11, comprising: determining a maximum sensing distance of the monostatic full-duplex long -pulse based radar mode based at least in part on the RCS of the object to be found while scanning.

13. The method of claim 11 or claim 12, comprising: determining a minimum sensing distance of the monostatic short-pulse based radar mode (705, 713,727,907, 911, 913) based at least in part on the RCS of the object to be found while scanning.

14. The method of any one of the previous claims, comprising: determining a maximum sensing distance of the monostatic full-duplex long -pulse based radar mode based at least in part on a speed of a target to be sensed.

15. The method of any one of the previous claims, comprising: determining a minimum sensing distance of the monostatic short-pulse based radar mode (705, 713, 727, 907, 911, 913) based at least in part on a speed of an object to be sensed.

16. The method of any one of the previous claims, wherein: the device (201,900,910,920, 1001) comprises a first transceiver and a second transceiver; and the first transceiver is operated in the monostatic full-duplex long -pulse based radar mode to sense the distances smaller than the first distance while the second transceiver is operated in the monostatic short-pulse based radar mode (705, 713,727,907, 911, 913) to sense distances no closer than the second distance.

17. The method of any one of the previous claims, wherein operating the device (20 1, 900,910,920, 1001) in the monostatic full-duplex long-pulse based radar mode comprises tilting a transmission of a radar pulse (103,205) downward towards an area to be sensed.

18. The method of any one of the previous claims, comprising: coordinating with a second device (201, 900, 910, 920, 1001) such that a radar pulse (103, 205) transmission from the device (201, 900, 910, 920, 1001) will not occur concurrently with a radar pulse (103, 205) transmission from the second device (201, 900, 910,920, 1001).

19. The method of any one of claims 1 through 17, comprising: coordinating with a second device (201,900,910,920, 1001) such that, when the device (201, 900, 910, 920, 1001) is operated in the monostatic full-duplex long-pulse based radar mode, the second device (201, 900, 910, 920, 1001) is operated in the monostatic short-pulse based radar mode (705, 713,727,907,911,913).

20. The method of any one of the previous claims, wherein: the device (201,900,910,920, 1001) comprises an antenna panel that comprises a plurality of antenna elements.

21. The method of claim 20, wherein: the monostatic full-duplex long-pulse based radar mode comprises using a first grouping of one or more of the antenna elements for transmission and a second grouping of one or more of the antenna elements for reception.

22. The method of any one of claims 20 and 21, wherein: the monostatic short-pulse based radar mode comprises using a third grouping of the antenna elements for transmission when scanning a first span of distances, and using a fourth grouping of the antenna elements for transmission when scanning a second span of distances, wherein the first span of distances is closer to the device (201, 900, 910, 920, 1001) than the second span of distances, and wherein the fourth grouping of the antenna elements comprises more antenna elements than the third grouping of the antenna elements.

23. The method of any one of the previous claims, wherein the device (201, 900, 910, 920, 1001) is a node in a telecommunications system.

24. The method of any one of claims 1 through 22, wherein the device (201, 900, 910, 920, 1001) is a User Equipment, UE, for use in a telecommunications system.

25. A computer program (1009) comprising instructions that, when executed by at least one processor (1003), causes the at least one processor (1003) to carry out the method according to any one of claims 1 through 24.

26. A carrier comprising the computer program (1009) of claim 25, wherein the carrier is one of an electronic signal, an optical signal, a radio signal, and a non-transitory computer readable storage medium (1005).

27. An apparatus (700, 710,720,900, 1001) for performing radar sensing of an environment by a device (201) in amobile communication system, the apparatus (700, 710, 720, 900, 1001) comprising circuitry configmed to cause the device (201) to: selectively operate (701, 711, 721,725,901) the device (201) in at least one of at least two radar modes, wherein the at least two radar modes comprise a monostatic full- duplex long-pulse based radar mode (703, 715, 723, 903, 909, 913) and a monostatic shortpulse based radar mode (705, 713,727,907,911,913), wherein a radar pulse (103,205) transmitted by the device (201) when operating in the monostatic full-duplex long -pulse based radar mode (703, 715, 723, 903, 909, 913) is longer than the radar pulse (103, 205) transmitted by the device (201) when operating in the monostatic short-pulse based radar mode (705, 713,727,907,911,913), and wherein selectively operating (701, 711, 721, 725) the device (201) in said at least one of the at least two radar modes comprises: operating the device (201) in the monostatic full-duplex long-pulse based radar mode when sensing is to be confined to distances smaller than a first distance from the device (201); and operating the device (201) in the monostatic short-pulse based radar mode (705, 713, 727,907,911,913) when sensing is to be no closer than a second distance from the device (201), wherein the second distance is greater than or equal to the first distance.

28. The apparatus (700,710,720,900, 1001) of claim 27, wherein the circuitry is further configured to cause the device (201) to decide which of the at least two radar modes is to be used by assessing one or more criteria.

29. The apparatus (700, 710, 720, 900, 1001) of any one of claims 27 through 28, wherein the second distance is equal to the first distance.

30. The apparatus (700, 710, 720, 900, 1001) of any one of claims 27 through 28, wherein the second distance is greater than the first distance.

31. The apparatus (700,710,720,900, 1001) of any one of claims 27 through 30, wherein the first distance is a minimum sensing distance of the monostatic short-pulse based radar mode (705, 713,727,907,911,913).

32. The apparatus (700,710,720,900, 1001) of any one of claims 27 through 31, wherein the second distance is a maximum sensing distance of the monostatic full-duplex long-pulse based radar mode.

33. The apparatus (700,710,720,900, 1001) of claim 30, wherein: the first distance is a minimum sensing distance of the monostatic short -pulse based radar mode (705, 713,727,907,911,913); the second distance is a maximum sensing distance of the monostatic full-duplex long-pulse based radar mode (703, 715,723,903,909,913); and the circuitry is further configured to cause the device (201) to: scan a region that spans distances between the first distance and the second distance by operating (729,913) the device (201) in the monostatic full-duplex long- pulse based radar mode and also operating (729,913) the device (201) in the monostatic shortpulse based radar mode (705, 713,727,907,911,913); and use, as sensing data of the region, sensing data collected by operating (729, 913) the device (201) in the monostatic full-duplex long-pulse based radar mode in combination with sensing data collected by operating (729, 913) the device (201) in the monostatic short- pulse based radar mode (705, 713,727,907,911,913).

34. The apparatus (700,710,720,900, 1001) of any one of claims 27 through 33, wherein: the monostatic full -duplex long-pulse based radar mode comprises using a first transmission power level when transmitting the radar pulse (103, 205);the monostatic short-pulse based radar mode (705, 713,727,907,911,913) comprises using a second transmission power level when transmitting the radar pulse (103, 205); and the second transmission power level is greater than the first transmission power level.

35. The apparatus (700, 710, 720, 900, 1001) of any one of claims 27 through 34, wherein the circuitry is further configured to cause the device (201) to obtain, from an application running on the device (201), range information pertaining to an area to be sensed.

36. The apparatus (700,710,720,900, 1001) of any one of claims 27 through 34, wherein the circuitry is further configured to cause the device (201) to obtain, from another device (201), range information pertaining to an area to be sensed.

37. The apparatus (700,710,720,900, 1001) of any one of claims 27 through 36, wherein: an object to be found has a radar cross section, RCS; and the circuitry is further configured to cause the device (201) to use the RCS while scanning for the object.

38. The apparatus (700,710,720,900, 1001) of claim 37, wherein the circuitry is further configmed to cause the device (201) to determine a maximum sensing distance of the monostatic full-duplex long-pulse based radar mode based at least in part on the RCS of the object to be found while scanning.

39. The apparatus (700, 710,720,900, 1001) of claim 37 or claim 38, wherein the circuitry is further configured to cause the device (201) to determine a minimum sensing distance of the monostatic short-pulse based radar mode (705, 713, 727, 907, 911, 913) based at least in part on the RCS of the object to be found while scanning.

40. The apparatus (700,710,720,900, 1001) of any one of claims 27 through 39, wherein the circuitry is further configmed to cause the device (201) todetermine a maximum sensing distance of the monostatic full-duplex long-pulse based radar mode based at least in part on a speed of a target to be sensed.

41. The apparatus (700, 710, 720, 900, 1001) of any one of claims 27 through 40, wherein the circuitry is configured to cause the device (201) to determine a minimum sensing distance of the monostatic short-pulse based radar mode (705, 713, 727, 907, 911, 913) based at least in part on a speed of an object to be sensed.

42. The apparatus (700, 710, 720, 900, 1001) of any one of claims 27 through 41, wherein the device (201) comprises a first transceiver and a second transceiver; and wherein the circuitry is further configured to cause the device (201) to operate the first transceiver in the monostatic full-duplex long-pulse based radar mode to sense the distances smaller than the first distance while operating the second transceiver in the monostatic short-pulse based radar mode (705, 713, 727, 907, 911, 913) to sense distances no closer than the second distance.

43. The apparatus (700, 710, 720, 900, 1001) of any one of claims 27 through 42, wherein operating the device (201) in the monostatic full-duplex long-pulse based radar mode comprises tilting a transmission of a radar pulse (103, 205) downward towards an area to be sensed.

44. The apparatus (700,710,720,900, 1001) of any one of claims 27 through 43, wherein the circuitry is further configured to cause the device (201) to coordinate with a second device (201) such that a radar pulse ( 103 , 205) transmission from the device (201) will not occur concurrently with a radar pulse (103,205) transmission from the second device (201).

45. The apparatus (700,710,720,900, 1001) of any one of claims 27 through 43, wherein the circuitry is further configured to cause the device (201) to coordinate with a second device (201) such that, when the device (201) is operated in the monostatic full-duplex long-pulse based radar mode, the second device (201) is operated in the monostatic short-pulse based radar mode (705, 713,727,907,911,913).

46. The apparatus (700, 710, 720, 900, 1001) of any one of claims 27 through45, whereinthe device (201) comprises an antenna panel that comprises a plurality of antenna elements.

47. The apparatus (700, 710,720,900, 1001) of claim 46, wherein: the monostatic full-duplex long-pulse based radar mode comprises using a first grouping of one or more of the antenna elements for transmission and a second grouping of one or more of the antenna elements for reception.48The apparatus (700,710,720,900, 1001) of any one of claims 46 and 47, wherein: the monostatic short -pulse based radar mode comprises using a third grouping of theantenna elements for transmission when scanning a first span of distances, and using a fourth grouping of the antenna elements for transmission when scanning a second span of distances, wherein the first span of distances is closer to the device (201) than the second span of distances, and wherein the fourth grouping of the antenna elements comprises more antenna elements than the third grouping of the antenna elements.

49. The apparatus (700,710,720,900, 1001) of any one of claims 27 through 48, wherein the apparatus (700,710,720,900, 1001) is a node in a telecommunications system.

50. The apparatus (700,710,720,900, 1001) of any one of claims 27 through 48, wherein the apparatus (700, 710,720,900, 1001) is a User Equipment, UE, for use in a telecommunications system.

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