阅读说明：本技术 用于毫米波应用的可切换反射式相移器 (Switchable reflective phase shifter for millimeter wave applications ) 是由 劳尔·伊诺森西奥·阿里迪奥 于 2020-02-26 设计创作，主要内容包括：本文公开的示例涉及一种用于毫米波应用的可切换反射式相移器。该可切换反射式相移器具有：可切换相移网络,该可切换相移网络具有用于响应于由控制模块提供的多个偏置电压而启动多个相位子范围的多个开关；以及反射式相移器,该反射式相移器用于生成在由多个开关中的给定开关启动的给定相位子范围内的相移。(Examples disclosed herein relate to a switchable reflective phase shifter for millimeter wave applications. The switchable reflective phase shifter has: a switchable phase shift network having a plurality of switches for actuating a plurality of phase sub-ranges in response to a plurality of bias voltages provided by a control module; and a reflective phase shifter for generating a phase shift within a given phase sub-range enabled by a given switch of the plurality of switches.)

1. A switchable reflective phase shifter comprising:

a switchable phase shift network comprising a plurality of switches for actuating a plurality of phase sub-ranges in response to a plurality of bias voltages provided by a control module; and

a reflective phase shifter to generate a phase shift within a given phase sub-range enabled by a given switch of the plurality of switches.

2. The switchable reflective phase shifter of claim 1, wherein the plurality of switches comprises a plurality of single pole, triple throw ("SP 3T") switches, the plurality of SP3T switches being triggered by the plurality of bias voltages provided by the control module.

3. The switchable reflective phase shifter of claim 2, wherein the plurality of SP3T switches comprises a first SP3T switch and a second SP3T switch coupled to a 120 ° delay line and a 240 ° delay line.

4. The switchable reflective phase shifter of claim 1, wherein the plurality of phase sub-ranges comprises a first phase sub-range of 0 ° to 120 °, a second phase sub-range of 120 ° to 240 °, and a third phase sub-range of 240 ° to 360 °.

5. The switchable reflective phase shifter of claim 1, wherein the reflective phase shifter comprises a distributed varactor network implemented by a lange coupler and a plurality of impedance lines.

6. The switchable reflective phase shifter of claim 5, wherein the Langer coupler is coupled to a first impedance line coupled to a first reflective load and a second impedance line coupled to a second reflective load.

7. The switchable reflective phase shifter of claim 6, wherein the first reflective load comprises a first varactor and a second varactor, the first varactor and the second varactor coupled to a third impedance line.

8. The switchable reflective phase shifter of claim 6, wherein the second reflective load comprises a third varactor and a fourth varactor, the third varactor and the fourth varactor coupled to a fourth impedance line.

9. The switchable reflective phase shifter of claim 5, wherein the reflective phase shifter reflects RF signals dispersed to the plurality of impedance lines with an increased phase range.

10. A beam steering vehicle radar for object identification, comprising:

a radar module comprising at least one beam steering antenna and at least one RFIC implementing a switchable reflective phase shifter to steer an RF beam across a field of view and receive reflections of the steered RF beam; and

a perception module to receive radar data corresponding to reflections of the steered RF beam and to generate control instructions to adjust steering of the RF beam.

11. The beam steering vehicle radar of claim 10, wherein the at least one beam steering antenna comprises a meta-structure antenna.

12. The beam steering vehicle radar of claim 10, wherein the radar module further comprises a transceiver to generate RF signals to be radiated as RF beams by the at least one beam steering antenna and to generate the radar data from received reflections of the steered RF beams.

13. The beam steering vehicle radar of claim 10, wherein the switchable reflective phase shifter comprises: a switchable phase shift network having a plurality of switches for actuating a plurality of phase sub-ranges based on a plurality of bias voltages; and a reflective phase shifter to generate a phase shift within a given phase sub-range enabled by a given switch of the plurality of switches.

14. The beam steering vehicle radar of claim 13, wherein the reflective phase shifter comprises a distributed varactor network implemented by a lange coupler and a plurality of impedance lines.

15. The beam steering vehicle radar of claim 14, wherein the reflective phase shifter reflects the RF signals dispersed to the plurality of impedance lines with an increased phase range.

16. The beam steering vehicle radar of claim 13, wherein the control instructions comprise instructions to adjust the plurality of bias voltages.

17. The beam steering vehicle radar of claim 10, wherein the perception module includes a machine learning module to detect and identify objects from the radar data.

18. The beam steering vehicle radar of claim 17, wherein the control data is generated based on detecting and identifying objects from the radar data.

19. A method for steering an RF beam in a beam steering vehicle radar for object detection and identification, comprising:

generating an RF signal for transmission;

providing a bias voltage to a switchable reflective phase shifter in the beam steering vehicle radar;

generating a phase-shifted RF signal with a phase shift corresponding to the bias voltage, the phase shift being within a first phase sub-range;

radiating the phase-shifted RF signals through a beam steering antenna to detect an object; and

switching the switchable reflective phase shifter to a second phase sub-range based on the detected object.

20. The method of claim 19, further comprising: providing control instructions to the beam steering vehicle radar to switch the switchable reflective phase shifter based on object detection data generated by a perception module when the object is detected from a reflection of the phase shifted RF signal.

Background

Millimeter wave applications have emerged to address the need for higher bandwidths and data rates. The millimeter wave spectrum covers frequencies between 30 and 300GHz and is capable of data rates of 10Gbits/s or higher with wavelengths in the range of 1 to 10 mm. Shorter wavelengths have different advantages including better resolution, high frequency reuse and directional beamforming, which are critical in wireless communication and autonomous driving applications. However, shorter wavelengths are susceptible to attenuation by the upper atmosphere and have a limited range (slightly above kilometers).

In many such applications, phase shifters are required to achieve a full range of phase shifts to steer the beam to a desired direction. Designing millimeter wave phase shifters is challenging because in miniature circuits, losses must be minimized while providing any phase shift within 0 to 360 °.

Drawings

The present application may be more fully understood by reference to the following detailed description taken in conjunction with the accompanying drawings, which are not to scale, and in which like reference numerals refer to like parts throughout, and in which:

FIG. 1 is a schematic diagram of a switchable reflective phase shifter for millimeter wave applications in accordance with various implementations of the subject technology;

FIG. 2 is a schematic diagram of a switchable reflective phase shifter as shown in FIG. 1 and in accordance with various implementations of the subject technology;

FIG. 3 is a schematic diagram of a varactor-based reflective phase shifter as shown in FIG. 2 and in accordance with various implementations of the subject technology;

FIG. 4 is a schematic diagram of a switchable phase network as shown in FIG. 2 and in accordance with various implementations of the subject technology;

FIG. 5 is a flow diagram of generating a desired phase shift by a switchable reflective phase shifter, as shown in FIG. 2 and in accordance with various implementations of the subject technology;

fig. 6 illustrates example values of a phase shift, a bias voltage, and a varactor control voltage of a switchable reflective phase shifter, as illustrated in fig. 2 and in accordance with various implementations of the subject technology;

FIG. 7 illustrates an MMIC layout of a switchable reflective phase shifter as shown in FIG. 2 and in accordance with various implementations of the subject technology;

FIG. 8 is a graph illustrating insertion loss across phase for a switchable reflective phase shifter as shown in FIG. 2 and according to various implementations of the subject technology;

FIG. 9 is a diagram illustrating phase shifts implemented by a switchable reflective phase shifter as shown in FIG. 2 and in accordance with various implementations of the subject technology;

FIG. 10 illustrates an example environment in which an object is detected and identified using a beam steering radar system with switchable reflective phase shifters in an autonomous vehicle, in accordance with various implementations of the subject technology;

FIG. 11 is a schematic diagram of an autopilot system for an autonomous vehicle in accordance with various implementations of the subject technology;

FIG. 12 is a schematic diagram of a beam steering radar system as shown in FIG. 11 and in accordance with various implementations of the subject technology;

FIG. 13 is a flow diagram for steering RF beams in a beam steering vehicle radar for object identification, according to various implementations of the subject technology; and

fig. 14 illustrates an example 5G application using switchable reflective phase shifters according to various implementations of the subject technology.

Detailed Description

A Switchable Reflective Phase Shifter ("SRPS") for millimeter wave applications is disclosed. By using varactor-based reflective phase shifters capable of operating at millimeter wave frequencies, SRPS is capable of generating any continuous phase shift within 0 ° to 360 °. SRPS employs a robust topology design with low amplitude variation across phases, minimized ESD effects, and small MMIC layout size, making it an ideal choice for many millimeter wave applications such as wireless communications, ADAS, and autopilot.

In particular, the SRPS described herein enables rapid scanning of the entire environment up to 360 ° in a fraction of the time of current autopilot systems, with improved performance, full-weather/full-condition detection, advanced decision making and interaction with multiple vehicle sensors through sensor fusion. The examples described herein provide enhanced phase shifting of transmitted RF signals to enable automatic vehicle-wide transmission, which is about 77GHz in the united states and has a 5GHz range, specifically 76GHz to 81 GHz. The examples described herein also reduce the computational complexity of the radar system and increase its transmission speed.

It should be understood that in the following description, numerous specific details are set forth in order to provide a thorough understanding of the examples. It should be understood, however, that the examples may be practiced without limitation to these specific details. In other instances, well-known methods and structures may not have been described in detail so as not to unnecessarily obscure the description of the examples. Further, these examples may be used in combination with each other.

Fig. 1 is a schematic diagram of a SRPS for millimeter wave applications, according to various examples. SRPS 100 has two main circuits: a switchable phase network 102 and a reflective phase shifter 104. The switchable phase network 102 includes delay lines and switches to enable phase shifting in the reflective phase shifter 104 in a set of phase sub-ranges (e.g., 90 ° phase sub-range, 120 ° phase sub-range, etc.). A set of bias voltages 106 is used to activate the switches in the switchable phase network 102. Each bias voltage activates a given switch and enables a phase shift in a given phase sub-range. The reflective phase shifter 104 is designed to generate a phase shift in each sub-range. In various examples, reflective phase shifter 104 is implemented with a set of varactors to achieve a continuous phase shift for a set of varactor control voltages.

A varactor is a variable capacitance diode whose capacitance changes with the applied varactor control voltage or reverse bias voltage. By varying the value of the control voltage, the capacitance of the varactor is varied within a given range of values. The design of varactors for millimeter wave applications is limited by the quality factor and tuning range, and the quality factor is well below desired levels. Varactors with wide tuning ranges in the millimeter wave spectrum are therefore difficult to implement, limiting their use in millimeter wave applications that may require a 360 ° phase shift to achieve their full potential. An ideal varactor (i.e., lossless nonlinear reactance) has a given capacitance range of about 20 to 80fF and no loss (Rs ═ 0 Ω). An ideal varactor can provide a phase shift in the range of about 52 ° to 126 °. In various applications where a 360 ° full phase shift is desired, such a phase shift is not sufficient.

SRPS 100 provides a solution to this limited phase shift range problem by introducing a distributed varactor network to generate any desired phase shift between 0 ° and 360 °. Each desired phase shift is generated in response to a bias voltage provided by the control module 106. In beam steering vehicle radar applications, the control module 106 is a perception module that instructs the beam steering antenna to steer the RF beam based on the detection and identification of the object. In wireless communication applications, the control module 106 is used to steer the RF beam as needed to improve wireless coverage to users (such as users in non-line-of-sight regions).

Referring now to fig. 2, fig. 2 shows a schematic diagram of a switchable reflective phase shifter as shown in fig. 1 and implemented according to various examples. SRPS 200 is shown with a switchable phase network 202 and a reflective phase shifter 204. The switchable phase network 202 has two single pole, three throw ("SP 3T") switches 206 and 208 to enable three phase sub-ranges in which the reflective phase shifter 204 can produce fine phase control. Phase sub-range 210 is enabled to generate a phase shift of 0 to 120 in reflective phase shifter 104, phase sub-range 212 is enabled to generate a phase shift of 120 to 240 in reflective phase shifter 204, and phase sub-range 214 is enabled to generate a phase shift of 240 to 360 in reflective phase shifter 204. When a corresponding bias voltage is input to the switchable phase network 202, the phase sub-range is enabled to cause the reflective phase shifter 204 to generate a phase shift within the phase sub-range. For example, when a bias voltage corresponding to the phase sub-range 210 is input to the switchable phase network 202, the reflective phase shifter 204 can generate a continuous phase shift within this sub-range of 0 ° to 120 °.

Fig. 3 shows a schematic diagram of a varactor-based reflective phase shifter 204. The reflective phase shifter 300 is a distributed varactor network implemented with a Lange coupler (Lange coupler)302, an impedance line 304 and 310, and a varactor 312 and 318. The lange coupler 302 divides the RF input signal into two signals that are 90 ° out of phase. The signals are reflected from matched reflective loads 320 and 322 and the phases of the RF outputs are combined. Impedance lines 304-310 may be, for example, quarter wavelength (λ/4) or other such values of transmit lines. Each of the lines 304-310 may have a different or the same length. The addition of the impedance lines 304-310 coupled to the varactors 312-318 creates a pure capacitance or pure inductance circuit depending on the varactors used. When an RF signal is input to the reflective phase shifter 300, the signal is distributed to the different lines 304 and 310 and reflected back with an increased phase range. The phase range of each varactor 312-318 is controlled by a varactor control voltage (not shown).

It should be noted that the reflective phase shifter 300 achieves a 360 ° full phase shift only if an ideal varactor is used. Practical varactors designed for millimeter wave applications are limited by the quality factor and tuning range. In fact, the tuning range of the millimeter wave varactor is much smaller than that of an ideal varactor. In the case of millimeter wave varactors, the reflective phase shifter 300 is capable of generating a phase shift within a given phase sub-range, for example, a phase shift within a 120 ° phase sub-range. Thus, by adding a switchable phase network to the SRPS design of fig. 1 and 2 to initiate different phase sub-ranges for the reflective phase shifter, a 360 ° full phase shift can be achieved.

Referring now to fig. 4, a schematic diagram of a switchable phase network as in fig. 2 is depicted, in accordance with various examples. The switchable phase network 400 is an S3PT switch having three circuit blocks 402-406 coupled to impedance lines 408-412. Each circuit block is enabled by a respective bias voltage, e.g., circuit block 402 is enabled by bias voltage S1, circuit block 404 is enabled by bias voltage S2, and circuit block 406 is enabled by bias voltage S3. Impedance lines 408 and 412 may be quarter-wave lines or other such values such that the output of each circuit block is within a given phase sub-range. Circuit block 402 may generate RF signals within a phase of 0 ° to 120 °, circuit block 404 may generate RF signals within a phase of 120 ° to 240 °, and circuit block 406 may generate RF signals within a phase of 240 ° to 360 °.

Fig. 5 illustrates a flow diagram for generating a desired phase shift by SRPS, as shown in fig. 2 and in accordance with various implementations of the subject technology. First, a bias voltage is input into the SRPS (500). The bias voltage activates a given throw switch (e.g., circuit block 402-406 in fig. 4) to generate a phase shift within a given phase sub-range (502). The throw switch then activates a fine-tuned phase shift control (504) triggered within the desired phase sub-range by a reflective phase shifter in the SRPS circuit.

Fig. 6 illustrates example values of the phase shift, bias voltage, and varactor control voltage of the SRPS as shown in fig. 2 and in accordance with various implementations of the subject technology. Table 600 shows delta and angular phase values within 0 ° to 120 ° and different varactor control voltages achieved for bias voltage S1, table 602 lists phase sub-range parameter values within 120 ° to 240 °, and table 604 lists phase sub-range parameter values within 240 ° to 360 °. The illustrated results demonstrate that the SRPS described herein has the capability of truly generating continuous phase shifts over the full phase range up to 360 °. This enables beam steering in the millimeter wave frequency range in 5G and automotive applications, thereby meeting the requirements of many applications.

Fig. 7 illustrates an example MMIC layout for SRPS in accordance with various implementations of the subject technology. The MMIC 700 is implemented in GaAs technology with circuit dimensions of about 1.65mm X2.9 mm, suitable for many millimeter wave applications. Fig. 8 is a graph 800 illustrating insertion loss across phases for the SRPS 200. The insertion loss across frequency and phase of the SRPS 200 is controlled and maintained at about 6.5 dB. In fig. 9, a graph 900 illustrating the phase shift achieved by the SRPS 200 illustrates its full phase capability up to 360 °.

The SRPS described herein can be applied to many millimeter wave applications, including beam steering radar applications in automotive vehicles. The beam steering radar implemented by the SRPS described herein is capable of steering the RF beam anywhere within 0 ° to 360 ° by the phase shift produced by the SRPS. Referring now to FIG. 10, an example environment for detecting and identifying objects using a beam steering radar system in an autonomous vehicle is shown. The autonomous vehicle 1000 is an autonomous vehicle having a beam steering radar system 1006, the beam steering radar system 1006 being configured to transmit radar signals to scan for FoV or a particular area. The entire FoV or portions thereof may be scanned by such a set of transmit beams 1018, which may be scanned in consecutive adjacent scan locations or in a particular or random order. It should be noted that the term FoV is used herein to refer to radar transmissions and does not imply an optical FoV with an unobstructed view. The scan parameters may also indicate the time interval between these incremental transmit beams, as well as the start and end angular positions for a full or partial scan.

In various examples, autonomous vehicle 1000 may also have other perception sensors, such as camera 1002 and lidar 1004. These perception sensors are not required by the autonomous vehicle 1000, but may be used to enhance the object detection capabilities of the beam steering radar system 1006. The camera sensor 1002 may be used to detect visible objects and conditions and facilitate the performance of various functions. Lidar sensor 1004 may also be used to detect objects and provide this information to adjust control of the vehicle. This information may include information such as congestion on the highway, road conditions, and other conditions that would affect the sensors, actions, or operations of the vehicle. Currently, camera sensors are used in Advanced Driver Assistance Systems ("ADAS") to assist drivers in performing functions such as parking (e.g., in rear view cameras). Cameras are capable of capturing texture, color, and contrast information at high levels of detail, but, like the human eye, they are susceptible to adverse weather conditions and lighting variations. Camera 1002 may have high resolution, but cannot resolve objects other than 50 meters.

Lidar sensors typically measure distance to an object by calculating the time it takes for a light pulse to travel to the object and back to the sensor. When positioned on top of a vehicle, the lidar sensor is capable of providing a 360 ° 3D view of the surrounding environment. Other approaches may use several lidar to provide a 360 ° full view at different locations around the vehicle. However, lidar sensors (e.g., lidar 1004) are still prohibitively expensive, oversized, weather condition sensitive, and limited to short range (typically less than 150 and 200 meters). On the other hand, radar has been used for vehicles for many years and operates under all weather conditions. Radar also uses far less processing than other types of sensors and has the advantage of detecting objects behind obstacles and determining the speed of moving objects. In terms of resolution, the laser beam of the lidar is focused within a small range, has a smaller wavelength than the RF signal, and is capable of achieving a resolution of about 0.25 degrees.

In various examples and as described in more detail below, the beam steering radar system 1006 can provide 360 ° true 3D vision and human-like interpretation of the autonomous vehicle's path and surrounding environment. The radar system 1006 is capable of shaping and steering an RF beam in all directions in a 360 ° FoV through a beam steering antenna module (with at least one beam steering antenna) and identifying objects quickly and with high accuracy over a long range of about 300 meters or more. The short range capability of camera 1002 and lidar 1004, along with the long range capability of radar 1006, enables sensor fusion module 1008 in autonomous vehicle 1000 to enhance its object detection and recognition.

Fig. 11 shows a schematic diagram of an autonomous driving system for an autonomous vehicle, according to various examples. The autopilot system 1100 is a system used in an autonomous vehicle that provides some or all of the automation of driving functions. The driving functions may include, for example, steering, accelerating, braking, and monitoring the surrounding environment and driving conditions in response to events such as changing lanes or speeds when it is desired to avoid a vehicle traveling on the road, a pedestrian crossing a street, an animal, etc. The autopilot system 1100 includes a beam steering radar system 1102 and other sensor systems, such as a camera 1104, laser radar 1106, infrastructure sensors 1108, environmental sensors 1110, operational sensors 1112, user preference sensors 1114, and other sensors 1116. Autopilot system 1100 also includes a communication module 1118, a sensor fusion module 1120, a system controller 1122, a system memory 1124, and a V2V communication module 1126. It should be understood that this configuration of the autopilot system 1100 is an example configuration and is not meant to be limited to the particular configuration shown in fig. 11. Additional systems and modules not shown in fig. 11 may be included in the autopilot system 1100.

In various examples, the beam steering radar system 1102 includes at least one beam steering antenna for providing dynamically steerable and steerable beams that may be focused on one or more portions of the 360 ° FoV of the vehicle. The beam radiated from the beam steering antenna reflects off of objects in the path of the vehicle and the surrounding environment and is received and processed by the radar system 1102 to detect and identify the objects. The radar system 1102 includes a perception module trained to detect and identify objects and control the radar module as needed. Camera sensor 1104 and lidar 1106 can also be used to identify objects in the path and surrounding environment of the autonomous vehicle, albeit within a very short range.

The infrastructure sensors 1108 may provide information from the infrastructure while driving, for example, from intelligent road configurations, billboard information, traffic alerts and indicators, including traffic lights, stop signs, traffic warnings, etc. This is an area of ongoing development and the uses and capabilities derived from this information are extremely large. The environmental sensors 1110 detect various external conditions such as temperature, humidity, fog, visibility, precipitation, etc. The operation sensors 1112 provide information about functional operations of the vehicle. This information may be tire pressure, oil level, brake wear, etc. The user preference sensor 1114 may be configured to detect conditions as part of a user preference. This may be temperature regulation, smart window shading, etc. Other sensors 1116 may include additional sensors for monitoring conditions within and around the vehicle.

In various examples, the sensor fusion module 1120 optimizes these various functions to provide an approximately comprehensive view of the vehicle and environment. Many types of sensors may be controlled by the sensor fusion module 1120. These sensors may coordinate with each other to share information and take into account the effect of one control action on another system. In one example, under congested driving conditions, a noise detection module (not shown) may identify the presence of multiple radar signals that may interfere with the vehicle. The perception module in the radar 1202 may use this information to adjust the scanning parameters of the radar to avoid these other signals and minimize interference.

In another example, environmental sensors 1110 may detect that the weather is changing and that visibility is decreasing. In this case, the sensor fusion module 1120 may determine to configure other sensors to improve the ability of the vehicle to navigate under these new conditions. Configuration may include turning off the camera or lidar sensor 1104 and 1106, or reducing the sampling rate of these visibility-based sensors. This effectively relies on the sensor(s) being adapted to the current situation. In response, the perception module also configures the radar 1102 for these conditions. For example, the radar 1102 may reduce the beamwidth to provide a more focused beam, and thus a finer perception capability.

In various examples, the sensor fusion module 1120 may send direct control to the antenna based on historical conditions and control. The sensor fusion module 1120 may also use some sensors within the system 1100 to act as feedback or calibration for other sensors. As such, the operational sensors 1112 may provide feedback to the perception module and/or the sensor fusion module 1120 to create templates, patterns, and control scenarios. These templates, patterns, and control situations are based on successful actions, or may be based on poor results, where the sensor fusion module 1120 learns from past actions.

Data from the sensors 1102-1116 may be combined in the sensor fusion module 1120 to improve the target detection and recognition performance of the autopilot system 1000. The sensor fusion module 1120 itself may be controlled by a system controller 1122, which system controller 1122 may also interact with and control other modules and systems in the vehicle. For example, the system controller 1122 may turn on and off the various sensors 1102-1116 as needed, or provide a stop indication to the vehicle upon identification of a driving hazard (e.g., a deer, pedestrian, cyclist, or another vehicle that is suddenly present in the vehicle path, flying debris, etc.).

All modules and systems in the autopilot system 1100 communicate with each other through a communication module 1118. The autopilot system 1100 also includes a system memory 1124 that can store information and data (e.g., static and dynamic data) for operating the system 1100 and the autonomous vehicle using the system 1100. The V2V communication module 1126 is used to communicate with other vehicles. The V2V communication module 1126 may also include information from other vehicles that is not visible to the vehicle user, driver or rider, and may assist in vehicle coordination to avoid accidents.

Fig. 12 illustrates a schematic diagram of a beam steering radar system, as illustrated in fig. 2 and in accordance with various implementations of the subject technology. The beam steering radar system 1200 is a "digital eye" with true 3D vision and capable of similar interpretation of the world by humans. The "digital eye" and human-like interpretation capabilities are provided by two main modules: a radar module 1202 and a perception module 1204. The radar module 1202 includes at least one beam steering antenna 1206 for providing dynamically controllable and steerable beams that may be focused on one or more portions of the 360 ° FoV of the autonomous vehicle. It should be noted that current beam steering antenna implementations are capable of steering beams up to 120-180 FoV. Multiple beam steering antennas may be required to provide steerability up to 360 ° full FoV.

In various examples, the beam steering antenna 1206 is integrated with an RFIC 1210 that includes the SRPS described herein for providing RF signals at multiple steering angles. The antenna may be a cellular structure antenna, a phased array antenna, or any other antenna capable of radiating RF signals at millimeter-wave frequencies. A meta-structure as generally defined herein is an engineered structure capable of controlling and manipulating incident radiation in a desired direction based on geometry. The meta-structure antenna may include various structures and layers including, for example, a feedback or power division layer 1218 to divide power and provide impedance matching, an RF circuit layer with an RFIC 1210 to provide steering angle control and other functions, and a meta-structure antenna layer with multiple microstrips, gaps, patches, vias, and the like. The meta-structure layer may comprise a metamaterial layer. Various configurations, shapes, designs, and sizes of beam steering antenna 1206 may be used to implement a particular design and satisfy particular constraints.

Portions of radar control are provided by the perception module 1204, the perception module 1204 acting as the control module 106 of fig. 1. The radar data generated by the radar module 1202 is provided to the perception module 1204 for object detection and identification. The radar data is acquired by a transceiver 1208, the transceiver 1208 having a radar chipset capable of generating RF signals radiated by the beam steering antenna 1206 and receiving reflections of these RF signals. Object detection and recognition in the perception Module 1204 is performed in a Machine Learning Module ("MLM") 1212 and a classifier 1214. Once an object is identified in the vehicle's FoV, the perception module 1204 provides object data and control instructions to the antenna control 1216 in the radar module 1202 for adjusting beam steering and beam characteristics as needed. In various implementations, the control instructions include instructions to provide different phase shifts by adjusting the bias voltage of the SRPS input into the RFIC 1210.

In various examples, the MLM 1212 implements a CNN, which in various examples is a full convolutional neural network ("FCN") having three stacked convolutional layers from input to output (additional layers may also be included in the CNN). Each of these layers also performs a linear start-up function of rectification and batch normalization to replace the traditional L2 normalization, and each layer has 64 filters. Unlike many FCNs, data is not compressed as it propagates through the network because the size of the input is relatively small and the runtime requirements can be met without compression. In various examples, the CNN may be trained with raw radar data, synthetic radar data, lidar data, then retrained with radar data, and so on. Multiple training options may be implemented for training the CNN to achieve good object detection and recognition performance.

Classifier 1214 may also include a CNN or other object classifier to enhance object recognition capabilities of perception module 1204 by using velocity information and micro-doppler characteristics in radar data acquired by radar module 1202. When an object moves slowly or outside of a roadway lane, then it is likely not a motor vehicle, but a person, animal, cyclist, etc. Similarly, when an object is moving on a highway at a high speed but below the average speed of other vehicles, the classifier 1214 uses the speed information to determine whether the vehicle is a truck or another object that tends to move more slowly. The location of the object (e.g., the rightmost lane of a highway in some countries (e.g., in the united states)) may indicate a slow moving vehicle. If the movement of the object does not follow the path of the road, the object may be an animal, for example, a deer running across the road. All of this information may be determined from various sensors and information available from the vehicle, including information provided from weather and traffic services as well as from other vehicles or the environment itself (such as intelligent roads and intelligent traffic signs).

It should be noted that the speed information is unique to the radar sensor. The radar data is in a multidimensional format (ri, θ i, φ φ i, Ii, vi) in the form of data tuples, where ri, θ i, φ i represent position coordinates of objects, where ri represents a range or distance between radar system 300 and objects along its line of sight, θ i is an azimuth angle, and φ i is an elevation angle, Ii is an intensity or reflectivity indicating an amount of transmit power returning to transceiver 1208, and vi is a velocity between radar system 1200 and objects along its line of sight. The position and velocity information provided by the sensing module 1204 to the radar module 1202 enables the antenna control 1210 to adjust its parameters accordingly.

Fig. 13 shows a flow diagram for steering an RF beam in a beam steering vehicle radar for object detection and identification, as in the beam steering vehicle radar 1200 of fig. 12. First, an RF signal is generated for transmission at a transceiver (1300). A bias voltage is provided to a switchable reflective phase shifter in an RFIC in a beam steering vehicle radar (1302). It should be noted that there may be multiple switchable reflective phase shifters in one RFIC and multiple RFICs in a beam steering vehicle radar, for example RFICs coupled to multiple antenna elements. Each switchable reflective phase shifter generates a phase shift within a first phase sub-range corresponding to a bias voltage of the transceiver to provide a phase shifted RF signal (1304) to a beam steering antenna (e.g., beam steering antenna 1206). The beam steering antenna then radiates the phase shifted RF signal to detect the object (1306). The switchable reflective phase shifters are then switched to a second sub-range of phases based on the detected object to steer the beam in another direction (1308). This may be in response to the object moving to another location on the road or another such example. SRPS enables autonomous vehicles to steer beams in any desired direction for object detection in both short and long ranges.

The SRPS described herein above may also be implemented in 5G applications, as shown in fig. 14. In the present application, the wireless communication module 1402 (e.g., a base station) incorporates a SRPS (e.g., SRPS 200 of fig. 2) as described herein to transmit and receive RF beams. For example, the SRPS implemented in the wireless transceiver of module 1402 is capable of steering an RF beam radiated from wireless module 1402 in any direction. During receive operations, SRPS may be used to align received RF beams that arrive at each radiating element of the receive antenna of module 1402 at different times. In another example, the SRPS implemented in the active reflectarray module 1404 reflects an RF beam transmitted from the wireless communication module 1402 to any direction to reach a user in a non-line-of-sight region. The desired direction is provided by a control module coupled to the reflect array module 1404 and in response to conditions in the environment 1400 that may affect wireless coverage to the user.

It should be appreciated that the foregoing description of the disclosed examples is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these examples will be readily apparent to those skilled in the art and to the spirit or scope of this disclosure. Thus, the present disclosure is not intended to be limited to the examples shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

As used herein, the phrase "at least one of … (with the terms" and "or" to separate any of the illustrated items) preceding a series of items modifies the list as a whole rather than each member of the list (i.e., each item). The phrase "at least one of …" does not require the selection of at least one item; rather, the phrase is allowed to include the following meanings: at least one of any one of the items, and/or at least one of any combination of the items, and/or at least one of each of the items. For example, the phrases "at least one of A, B and C" or "at least one of A, B or C" each mean a only a, only B, or only C; A. any combination of B and C; and/or A, B and C. Furthermore, to the extent that the terms "includes," "has," "having," "including," and the like are used in either the detailed description or the claims, such terms are intended to be inclusive in a manner similar to the term "comprising" as "comprising" is interpreted when employed as a transitional word in a claim.

Reference to an element in the singular is not intended to mean "one and only one" unless explicitly so stated, but rather "one or more. The term "some" refers to one or more. Underlined and/or italicized headings and subheadings are used for convenience only, should not limit the subject technology, and are not intended to imply interpretation of the description of the associated subject technology. All structural and functional equivalents to the elements of the various configurations described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the subject technology. Furthermore, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the above description.

While this specification contains many specifics, these should not be construed as limitations on the scope of what may be claimed, but rather as descriptions of particular implementations of the subject matter. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

The subject matter of this specification has been described in terms of particular aspects, but other aspects can be practiced and are within the scope of the appended claims. For example, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. The actions recited in the claims can be performed in a different order and still achieve desirable results. For example, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. Moreover, the separation of various system components in the aspects described above should not be understood as requiring such separation in all aspects, and it should be understood that the described program components and systems can generally be integrated together in a single hardware product or packaged into multiple hardware products. Other variations are within the scope of the following claims.