System, method and device for wireless device interference cancellation

Abstract

To provide systems, methods and devices for performing interference cancellation operations for wireless devices.SOLUTION: The method includes transmitting, with a transmitter of a transceiver included within the wireless device, an input signal, receiving, at a receiver of the transceiver, an interference signal that is a leakage signal, performing an interference cancellation operation on the interference signal based at least in part on one or more adjustments of the receiver determined based on the input signal and the received interference signal, and generating, with the transceiver, an output signal based at least in part on the interference cancellation operation.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] This disclosure relates to wireless devices, and more particularly to enhanced interference cancellation for such wireless devices. [Background technology]

[0002] A wireless device may include a transceiver configured to generate and receive wireless signals according to one or more wireless communication protocols. Accordingly, such a transceiver may include a transmit chain and a receive chain configured to perform transmit and receive operations, respectively. Because the transmit chain and the receive chain are not completely isolated, and leakage from the transmit chain can affect signals received at the receive chain, conventional wireless devices remain limited. [Brief explanation of the drawings]

[0003] [Figure 1] 1 illustrates an example of a wireless system configured in accordance with some embodiments. [Figure 2] 1 illustrates an example of a wireless device configured in accordance with some embodiments. [Figure 3] 1 illustrates an example of a wireless device configured to perform interference cancellation operations in accordance with some embodiments. [Figure 4] 1 illustrates another example of a wireless device configured to perform interference cancellation operations in accordance with some embodiments. [Figure 5] 10 illustrates a further example of a wireless device configured to perform interference cancellation operations in accordance with some embodiments. [Figure 6] 1 illustrates another example of a wireless device configured to perform interference cancellation operations in accordance with some embodiments. [Figure 7] 1 illustrates an example of a method for interference cancellation performed in accordance with some embodiments. [Figure 8]10 illustrates another example of a method for interference cancellation, performed in accordance with some embodiments. [Figure 9] 10 illustrates a further example of a method for interference cancellation, performed in accordance with some embodiments. [Figure 10] 10 illustrates another example of a method for interference cancellation, performed in accordance with some embodiments. [Figure 11] 10 illustrates a further example of a method for interference cancellation performed in accordance with some embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0004] In the following description, numerous specific details are set forth to provide a thorough understanding of the presented concepts. The presented concepts may be practiced without some or all of these specific details. In other instances, well-known processing operations have not been described in detail so as not to unnecessarily obscure the concepts being described. While some concepts will be described in conjunction with specific examples, it should be understood that these examples are not intended to be limiting.

[0005] A wireless device may include a transceiver including components configured to perform transmit and receive operations for wireless communication. For example, the transceiver may include a transmit chain of components that generate signals provided to an antenna for transmission and a receive chain of components that receive signals via the antenna. In some embodiments, the wireless device may switch between a wireless communication mode and a radar mode. When in the wireless communication mode, the transceiver may be configured to transmit and receive data packets according to a wireless communication protocol, e.g., a WiFi protocol. When in the radar mode, the transceiver may be reconfigured to perform radar operations based on transmitting signals and receiving reflected signals during the radar mode.

[0006] The proximity of the transmitting and receiving components and the sharing of an antenna can result in interference between the transmit and receive chains. For example, leakage currents or signals can originate from the transmit chain and be received by the receive chain as signal interference. This type of interference can be problematic and can hinder the accuracy of radar detection operations.

[0007] Accordingly, embodiments disclosed herein provide techniques for reducing and / or eliminating such interference components. As described in more detail below, several different interference cancellation operations can be sequentially and dynamically performed to reduce the amount of interference experienced by a transceiver's receive chain. For example, coarse adjustments may be performed using voltage attenuators and phase shifters. Furthermore, fine adjustments may be performed via one or more adaptive filters. Furthermore, the use of such voltage attenuators, phase shifters, and adaptive filters may be configured dynamically and in response to a determination regarding whether such interference cancellation operations should be performed. In this manner, sequential interference cancellation operations may be performed at different locations along the receive chain to improve the accuracy and effectiveness of interference mitigation, and selection of such interference cancellation operations may be dynamically performed so that interference cancellation operations are performed efficiently and as needed.

[0008] 1 illustrates an example of a wireless system configured in accordance with some embodiments. Accordingly, a system, e.g., system 100, may include a wireless device used for wireless communication and also configured as a radar device capable of detecting the presence of an object using a wireless communication channel associated with such wireless device. As described in more detail below, the wireless device included in system 100 may be configured to reduce leakage currents that may otherwise affect such presence detection operations, thereby improving the effectiveness and accuracy of such presence detection operations.

[0009] In some embodiments, system 100 includes a wireless device 102 configured to transmit and receive wireless signals according to one or more communication protocols. For example, wireless device 102 may include one or more transceivers, e.g., transceiver 104, configured to transmit and receive signals according to a wireless communication protocol, e.g., a Wi-Fi protocol. In various embodiments, wireless device 102 further includes a processing device, e.g., processing device 106, configured to implement various hardware and logic associated with transceiver 104 and its associated wireless communication protocol. For example, processing device 106 may be configured to implement a medium access control (MAC) layer configured to control hardware associated with the wireless transmission medium, e.g., associated with the Wi-Fi transmission medium.

[0010] In various embodiments, the wireless device 102 is within communication range of one or more devices or entities. In one example, the wireless device 102 is within range of a device 108, which may be another wireless device. Accordingly, the device 108 may also include a transceiver and associated processing logic configured to facilitate wireless communication in accordance with a wireless communication protocol, e.g., a WiFi protocol. Thus, the wireless device 102 may be configured to establish a wireless connection with the device 108 and to transmit and receive data packets to and from the device 108. In one example, the wireless device 102 may be configured as a central device, e.g., an access point (AP), and the device 108 may be configured as a peripheral device, e.g., a station (STA).

[0011] Additionally, wireless device 102 is also within range of entity 110. In various embodiments, entity 110 may be an object or person within range of wireless device 102 and may be the target of a radar ranging operation when wireless device 102 is in radar mode. As described in more detail below, wireless device 102 is configured to identify the presence of entity 110 based on radar operations performed using a wireless communication channel that may be used to communicate with devices, e.g., device 108. In this manner, system 100 may support wireless communication and presence detection associated with entities, e.g., objects and people, within range of wireless device 102.

[0012] Additionally, as described in more detail below, components of the wireless device 102 may be configured to reduce interference experienced during such presence detection operations. For example, calibration operations may be performed to identify and selectively remove leakage signal components, thus removing such leakage signal components from signals received by the transceiver 104. Additional details regarding such leakage signals and calibration operations are described in more detail below.

[0013] Figure 2 illustrates an example of a wireless device configured in accordance with some embodiments. More particularly, Figure 2 illustrates an example of a system, e.g., system 200, that may include wireless device 201. It should be appreciated that wireless device 201 may be any one of the wireless devices described above with reference to Figure 1, e.g., wireless device 102 and device 108.

[0014] In various embodiments, wireless device 201 includes one or more transceivers, e.g., transceiver 204. In one example, system 200 includes transceiver 204 configured to transmit and receive signals using an antenna, e.g., antenna 221. As described above, transceiver 204 may be a Wi-Fi transceiver. Thus, transceiver 204 may be compatible with a wireless communication protocol, e.g., a WiFi protocol. In various embodiments, transceiver 204 includes a modulator and demodulator configured to generate and receive signals via antenna 221, as well as one or more buffers and filters. Thus, as described in more detail below, transceiver 204 may include chains of components, e.g., a transmit chain and a receive chain, configured to perform such operations. Each of the transmit chain and receive chain may be included within a transmitter and receiver, e.g., transmitter 230 and receiver 232, respectively. Additionally, as described in more detail below, the transceiver 204 and switch 202 may be configured to perform interference cancellation operations to remove components of the leakage signal that may otherwise occur within the transceiver 204 .

[0015] In various embodiments, system 200 further includes one or more processing devices, e.g., processing device 224, which may include logic implemented using one or more processor cores. Accordingly, processing device 224 is configured to implement logic for presence detection operations. For example, processing device 224 may be configured to estimate the presence of one or more entities within wireless communication range of wireless device 201 using wireless connection metrics and other channel information. Accordingly, processing device 224 may be configured to perform radar operations and presence determination operations when configured in radar mode. In one example, switching between communication mode and radar mode may be implemented via logic implemented in firmware. Accordingly, processing device 224 includes processing elements, which may be implemented in firmware, configured to perform wireless communication operations in which data packets are transmitted and received, perform presence detection operations, and perform operations to switch between the two. It should be appreciated that radar operations and calculations may be any suitable radar calculation techniques using frequency and phase measurements and data and other available signal metrics.

[0016] The processing device 224 includes one or more components configured to implement a medium access control (MAC) layer configured to control hardware associated with a wireless transmission medium, e.g., a Wi-Fi transmission medium. In one example, the processing device 224 may be configured to implement a driver, e.g., a Wi-Fi driver. Thus, the processing device 224 may include components associated with the transceiver 204, e.g., a MAC layer, a packet traffic arbiter, and a scheduler. In various embodiments, the processing device 224 includes processing blocks, e.g., the processor core block 210 and the DSP core block 212, to implement these features. In various embodiments, the scheduler may also be configured to switch between a data communication mode and a radar mode, thus enabling different configurations of the various cancellation blocks.

[0017] System 200 further includes a switch 202 coupled to antenna 221. In various embodiments, switch 202 may include various components, such as a radio frequency (RF) switch, a diplexer, and a filter. Thus, switch 202 may be configured to select which transmit chain or receive chain is coupled to antenna 221 for transmission / reception. As described in more detail below, switch 202 may also be configured to couple to electrical termination during some interference cancellation operations. In this manner, termination switch 202 can improve the accuracy of such interference cancellation operations. In some embodiments, electrical termination may include coupling the switch to electrical ground or simply leaving the switch open or floating.

[0018] System 200 includes a memory system 208 configured to store one or more data values ​​associated with interference removal operations, which are described in more detail below. Accordingly, memory system 208 includes a storage device, which may be a non-volatile random access memory (NVRAM), configured to store such data values ​​and may further include a cache configured to provide a local cache. In various embodiments, system 200 further includes a host processor 214 configured to perform processing operations performed by system 200.

[0019] It should be appreciated that one or more of the above-described components may be implemented on a single integrated circuit or on different integrated circuits. For example, the transceiver 204 and the processing device 224 may be implemented on the same integrated circuit, e.g., the integrated circuit 220. In other examples, the transceiver 204 and the processing device 224 may each be implemented on their own integrated circuit and thus may be separately located as a multi-chip module or on a common substrate, such as a printed circuit board (PCB). It should be appreciated that the components of the system 200 may be implemented in a variety of contexts, for example, in the context of a smart home environment, an automotive environment, or a wireless environment including Internet of Things (IoT) devices.

[0020] 3 illustrates an example of a wireless device configured to perform interference cancellation operations, according to some embodiments. Similar to those described above, various calibration operations may be performed to cancel interference that might otherwise occur between the transmitting and receiving components of a transceiver. For example, a wireless device, e.g., wireless device 300, may include various components configured to transmit and receive signals via an antenna. As described in more detail below, one or more components of wireless device 300 may be configured to cancel voltage and phase components of leakage signals that might otherwise be received by the receiving component of the transceiver.

[0021] 3, the transceiver of the wireless device 300 may include transmit chain components, such as a digital-to-analog converter (DAC) 302, a low-pass filter (LPF) 304, a mixer 306, and a power amplifier (PA) 308. In various embodiments, a digital input is provided to the DAC 302 from one or more other components of the wireless device 300, such as a processing device configured to generate a digital signal for transmission. In various embodiments, the input signal may be an arbitrary waveform generated for a calibration operation. For example, the input signal may include a test pattern defined by an entity, such as a manufacturer.

[0022] The wireless device 300 may also include receive chain components, such as a low-noise amplifier (LNA) 316, a mixer 320, an LPF 322, and an analog-to-digital converter (ADC) 324. Accordingly, a signal may be received from an antenna coupled to the switch 310, and the received signal may be provided as an output via the ADC 324. As described above, during operation, a leakage signal may be received in the receive chain based on activity of the transmit chain. Accordingly, as described in more detail below, the wireless device 300 may include a voltage attenuator 312 and a phase shifter 314 configured to mitigate components of the leakage signal.

[0023] In various embodiments, the wireless device 300 further includes a received signal strength indicator (RSSI) detector 318 configured to detect an analog signal output by the LNA 316 and convert the detected analog signal to discrete levels. Accordingly, the RSSI detector 318 may include a small-resolution DAC configured to generate an output signal having discrete levels corresponding to the received input. In various embodiments, the output of the RSSI detector 318 is provided to the voltage attenuator 312 and configured to control the operation of the voltage attenuator 312. More specifically, a lookup table may be used to map the discrete levels to voltage adjustments. As described in more detail below, the voltage attenuator 312 may be adjusted until the detected signal from the LNA 316 falls below a specified threshold, which may be determined by an entity, e.g., a manufacturer. The specified threshold may represent an acceptable amplitude of the leakage signal.

[0024] In various embodiments, the output of the ADC 324 may be provided to the phase shifter 314, and the output of the ADC may be mapped to a phase adjustment applied to the phase shifter 314. In various embodiments, the adjustments for the voltage attenuator 312 and the phase shifter 314 may be determined based on an exhaustive search or steepest descent algorithm to identify the configuration and adjustments that achieve the best cancellation. Thus, during the calibration process, the voltage attenuator 312 and the phase shifter 314 may be configured to cancel and mitigate components of the leakage signal. As described in more detail below, additional interference cancellation operations may be performed further downstream in the receive chain to further refine the interference cancellation of the leakage signal.

[0025] 4 illustrates another example of a wireless device configured to perform interference cancellation operations in accordance with some embodiments. Similar to that described above, the wireless device, e.g., wireless device 400, may include transmit chain components, e.g., a DAC 402, an LPF 404, a mixer 406, and a power amplifier (PA) 408. The wireless device 400 may also include receive chain components, e.g., an LNA 416, a mixer 420, an LPF 422, and an ADC 424. The wireless device 400 may further include a switch 410 configured to manage coupling to an antenna.

[0026] In various embodiments, the wireless device 400 further includes an adaptive filter 428 and a DAC 426 configured to perform additional interference cancellation operations. More specifically, the adaptive filter 428 is configured to receive the output of the ADC 424, which may also provide an error signal for interference cancellation in response to a training signal being input to the DAC 402 during a calibration phase. Additionally, the adaptive filter 428 may also receive the input training signal provided to the DAC 402. The adaptive filter 428 may be configured to apply one or more parameter estimation techniques, for example, a least mean squares equation with several weights within the least mean squares equation. In various embodiments, the weights may be iteratively varied until the weights converge. Furthermore, the weights may be determined based on a least mean squares (LMS) or recursive least squares (RLS) algorithm with a step size configured to implement gear shifting to facilitate fast convergence and a small mean square error. An example of the relationship between the parameters and adjustments of the weights is described with reference to equations (1) through (4) shown below. Y=L+N (1) E=L2-Y (2) W=W+k×E×Y (3) L2=W T ×L1 (4)

[0027] In various embodiments, L is the leakage signal, N is the noise figure, and Y is the received signal including both. Furthermore, E is the error signal, L1 is the input training signal, and L2 is the output of the adaptive filter 428 and the DAC 426. Furthermore, W represents a weight, and k is a scaling factor. As described above, W may be iteratively adjusted until the amplitude of E drops below a specified threshold. In this manner, the adaptive filter 428 and the DAC 426 may be configured during the calibration process, and their outputs may be available for normal operation of the wireless device 400. As shown in FIG. 4, the output of the DAC 426 may be provided to a point upstream of the LPF 422. Thus, the wireless device 400 may be configured so that the calibration operation is performed before the LPF 422 and does not incur the band limitation of the LPF 422. When performed in this manner, this type of calibration operation can be performed while avoiding saturation of the LPF 422. As will be described in more detail below, switch 410 may be configured to be coupled to circuit ground during a calibration operation.

[0028] 5 illustrates a further example of a wireless device configured to perform interference cancellation operations in accordance with some embodiments. Similar to that described above, a wireless device, e.g., wireless device 500, may include transmit chain components, e.g., a DAC 502, an LPF 504, a mixer 506, and a power amplifier (PA) 508. Wireless device 500 may also include receive chain components, e.g., an LNA 516, a mixer 520, an LPF 522, and an ADC 524. Wireless device 500 may further include a switch 510 configured to manage coupling with an antenna.

[0029] In various embodiments, the wireless device 500 further includes an adaptive filter 528 and a DAC 526 configured to perform additional interference cancellation operations. Similar to the above, the adaptive filter 528 is configured to receive the output of the ADC 524, which may also provide an error signal for interference cancellation in response to a training signal being input to the DAC 502 during a calibration phase. Additionally, the adaptive filter 528 may also receive the input training signal provided to the DAC 502. As described above, the adaptive filter 528 may be configured to apply one or more parameter estimation techniques, e.g., a least mean squares equation with several weights within the least mean squares equation. In various embodiments, the weights may be iteratively varied until the weights converge. As described above, the weights may be iteratively adjusted until the amplitude of the error signal, which may be the output of the ADC 524, drops below a specified threshold.

[0030] 5, the output of the DAC 526 may be provided to a point downstream of the LPF 522. Thus, the wireless device 500 can be configured such that a calibration operation is performed after the LPF 522, providing additional fine tuning of the calibration operation. In various embodiments, removal in the analog domain before the ADC 524 improves the dynamic range and signal-to-noise ratio (SNR) of the output signal. In one example, when the adaptive filter 528 targets a smaller mean-squared error, removal in the digital domain can improve accuracy. As described in more detail below, the switch 510 may be configured to couple to an appropriate termination during the calibration operation.

[0031] FIG. 6 illustrates another example of a wireless device configured to perform interference cancellation operations in accordance with some embodiments. Additionally, FIG. 6 illustrates multiple interference cancellation operations performed in a combined manner. Similar to the above, a wireless device, e.g., wireless device 600, may include transmit chain components, e.g., a DAC 602, an LPF 604, a mixer 606, and a power amplifier (PA) 608. Wireless device 600 may also include receive chain components, e.g., an LNA 616, a mixer 620, an LPF 622, and an ADC 624. Wireless device 600 may further include a switch 610 configured to manage coupling with an antenna.

[0032] Similar to the above, in various embodiments, the wireless device 600 further includes a voltage attenuator 612, a phase shifter 614, and an RSSI detector 618 that may be configured to perform a first interference cancellation operation. Thus, the voltage attenuator 612, the phase shifter 614, and the RSSI detector 618 may be configured to adjust the phase and voltage to reduce the leakage signal component during the first interference cancellation operation.

[0033] The wireless device 600 may further include an adaptive filter 628 and a DAC 626 configured to implement a parameter estimation technique and perform a second interference cancellation operation. Similar to the above, iterative adjustments may be made to weights in the least mean squares equation of the adaptive filter 628 to further reduce the leakage signal component during the second interference cancellation operation. Furthermore, as described above, this type of second interference cancellation operation may be performed by combining provided upstream of the LPF 622.

[0034] The wireless device 600 may further include an adaptive filter 632 and a DAC 630 configured to implement a parameter estimation technique and perform a third interference cancellation operation. Similar to the above, iterative adjustments may be made to weights in the least mean squares equation of the adaptive filter 632 to further reduce leakage signal components during the third interference cancellation operation. Furthermore, as described above, this type of third interference cancellation operation may be performed by combining provided downstream of the LPF 622. In this manner, multiple stages of interference cancellation operations may be performed and combined as part of an overall calibration process.

[0035] 7 illustrates an example of a method for interference cancellation performed in accordance with some embodiments. Similar to that described above, various interference cancellation operations can be performed to mitigate interference that may result from, for example, leakage between the transmit and receive chains. Thus, a method, such as method 700, can be performed to perform an interference cancellation operation to mitigate and reduce this type of interference.

[0036] Method 700 may perform operation 702, in which an input signal may be transmitted. Similar to above, the input signal may be a designated signal, e.g., a training signal, generated and transmitted through the transmit chain of the transceiver during a calibration phase. Thus, the training signal may have a known data pattern as well as one or more transmit parameters configured to mimic a signal used during radar detection operations.

[0037] Method 700 may perform operation 704, in which an interfering signal may be identified. As described above, a component coupled to a receive chain of a transceiver may detect a signal received at the receive chain as a result of a transmission. For example, interference may occur at the receive chain as a result of transmit activity on the transmit chain. In one example, the interference may be leakage between a transmit chain and a receive chain, where a leakage signal may be received at the receive chain while the transmit chain transmits an input signal. In various embodiments, the interfering signal may be identified by a component, such as an RSSI detector.

[0038] Method 700 may perform operation 706, in which one or more interference cancellation operations may be performed. Similar to what was described above and as described in more detail below, one or more interference cancellation operations may be performed during a calibration phase. As described above and as described in more detail below, the interference cancellation operations may be performed at various different stages of the receive chain and may include adjusting components, such as voltage attenuators, phase shifters, and adaptive filters, to mitigate interfering signals.

[0039] Method 700 may perform operation 708, in which an output may be generated based on one or more interference cancellation operations. Thus, once the calibration phase is complete, the transceiver may return to radar operation. Based on the calibration described above, the receive chain may receive the radar signal, mitigate interference that may occur due to leakage, and generate an output representative of the received signal.

[0040] 8 illustrates another example method for interference cancellation performed in accordance with some embodiments. Similar to that described above, an interference cancellation operation can be performed to mitigate interference that may result from leakage between the transmit and receive chains. As described in more detail below, a method, e.g., method 800, can be performed to perform multiple stages of interference cancellation operations to calibrate the transceiver and improve the effectiveness of interference mitigation and cancellation during radar operation of the transceiver.

[0041] Method 800 may perform operation 802, in which an input signal may be transmitted. In various embodiments, the input signal is a designated signal, e.g., a training signal, generated and transmitted through the transmit chain of the transceiver during a calibration phase. Thus, the training signal may have a known data pattern as well as one or more transmit parameters configured to mimic a signal used during radar detection operations.

[0042] As discussed above, the transceiver may be a wireless communication transceiver. Accordingly, the transceiver and associated processing logic may switch from a communication mode to a radar mode and initiate a calibration phase to calibrate the transceiver. For example, once switched to radar mode, transmission of training or test signals may begin. In various embodiments, as discussed above, this type of mode switching may be managed by firmware contained within the processing device.

[0043] Method 800 may perform operation 804, in which an interfering signal may be identified. As described above, a component coupled to a receive chain of a transceiver may detect a signal received at the receive chain, which may be interference resulting from transmit activity on the transmit chain. In one example, the interference may be leakage between the transmit chain and the receive chain, where a leakage signal may be received at the receive chain while the transmit chain transmits an input signal.

[0044] In various embodiments, the interfering signal may be identified by a component, such as an RSSI detector. Further, during operation 804, the RSSI detector may convert a detected signal, which may be detected at the output of an LNA included in the receive chain, into one or more discrete voltage levels for use by one or more other components, such as a voltage attenuator.

[0045] Method 800 may perform operation 806, in which a first interference cancellation operation may be performed based on the phase shift and attenuation operation. Thus, as described above, a voltage attenuator and a phase shifter coupled between the transmit chain and the receive chain may be configured based on the output of the RSSI detector and the output of the receive chain. More specifically, adjustments to the voltage attenuator and the phase shifter may be made until the output of the receive chain falls below a first specified threshold amplitude and / or until the output of the LNA falls below a detection threshold of the RSSI detector.

[0046] The method 800 may perform operation 808, in which a second interference cancellation operation may be performed based on the first filtering operation. Similar to the above, the second interference cancellation operation may include the use of a first adaptive filter prior to the LPF included in the receive chain. Accordingly, one or more weights of the first adaptive filter may be adjusted until the output of the receive chain falls below a second specified threshold amplitude.

[0047] It should be appreciated that the second interference cancellation operation may be performed dynamically and in response to an interfering signal detection after the first cancellation operation. For example, if the output of the receive chain continues to contain interference that exceeds an acceptable threshold after the first cancellation operation, the second interference cancellation operation may be performed. In this example, the acceptable threshold may be determined by an entity, such as a manufacturer or user, and may represent an overall tolerance limit for signal interference.

[0048] The method 800 may perform an operation 810 in which a third interference cancellation operation may be performed based on the second filtering operation. Similar to the above, the third interference cancellation operation may include the use of a second adaptive filter after the LPF included in the receive chain. Accordingly, one or more weights of the second adaptive filter may be adjusted until the output of the receive chain falls below a third specified threshold amplitude. It should be appreciated that the third interference cancellation operation may be performed dynamically and in response to interfering signal detection after the second cancellation operation. For example, if the output of the receive chain continues to contain interference above an acceptable threshold after the second cancellation operation, the third interference cancellation operation may be performed.

[0049] Method 800 may perform operation 812, in which an output may be generated based on the first, second, and third interference cancellation operations. Thus, once the calibration phase is complete, the transceiver may return to radar operation. The receive chain may receive the radar signal and may sequentially perform the first, second, and / or third interference cancellation operations at different stages of the receive chain. The result may be provided as an output representing the received signal.

[0050] 9 illustrates a further example of a method for interference cancellation performed in accordance with some embodiments. As described in more detail below, a method, such as method 900, may be performed to perform calibration operations for various components, such as voltage attenuators and phase shifters. In this manner, an initial stage of interference cancellation may be performed.

[0051] Method 900 may perform operation 902, in which an input signal may be transmitted using the transceiver. In various embodiments, the input signal is a designated signal, e.g., a training signal, generated and transmitted through the transmit chain of the transceiver during a calibration phase. Thus, the training signal may have a known data pattern as well as one or more transmit parameters configured to mimic a signal used during radar detection operations.

[0052] Method 900 may perform operation 904, in which the interfering signal may be detected by an RSSI detector included in a receive chain of the transceiver. Thus, the RSSI detector may detect a signal received by the receive chain, which may be interference resulting from transmit activity on the transmit chain. Furthermore, the RSSI detector may convert the detected signal, which may be detected at the output of an LNA included in the receive chain, into one or more discrete voltage levels based on the amplitude of the detected interfering signal.

[0053] Method 900 may perform operation 906, in which a first adjustment operation may be performed for a voltage attenuator based on the output of the RSSI detector. Thus, the output of the RSSI detector may be provided as an input to the voltage attenuator and may be configured to cause the voltage attenuator to implement a voltage offset based on the received input. Similar to the above, a specified mapping, which may be stored in a lookup table, may be used to map the RSSI detector output value to a voltage offset applied by the voltage attenuator. In various embodiments, a search or other suitable algorithm, e.g., a steepest descent algorithm, is used to identify the voltage and phase adjustment that results in the smallest RSSI value.

[0054] The method 900 may perform operation 908, in which a second adjustment operation may be performed for the phase shifter based on the output of an ADC included in the receive chain of the transceiver. Thus, the output of the receive chain may be sampled at the output of the ADC, and the output may be provided as an input to the phase shifter. Similar to the above, adjustment of such a phase shifter may be made at least in part based on a mapping determined based on an exhaustive search or steepest descent algorithm.

[0055] 10 illustrates another example of a method for interference cancellation performed in accordance with some embodiments. As described in more detail below, a method, e.g., method 1000, may perform additional calibration operations for various components, e.g., adaptive filters. In this manner, additional stages of interference cancellation may be performed.

[0056] Method 1000 may perform operation 1002, in which it may be determined that an interference cancellation operation should be performed. As described above, this type of determination may be made dynamically and in response to interference signal detection. For example, this type of interference signal detection may occur based on the output of a receive chain exceeding an acceptable threshold after an initial interference cancellation operation. In this manner, additional stages of interference cancellation may be performed dynamically.

[0057] Method 1000 may perform operation 1004, in which a transmit / receive (T / R) switch of the wireless device may be grounded. Thus, similar to what was described above with reference to FIG. 2, the T / R switch may be configured to manage coupling between the transmit chain, the receive chain, and the antenna. In various embodiments, the T / R switch may be configured to be coupled to circuit ground. When coupled to ground, the input to the receive chain may mimic no signal being received, such as when no object is present within range of radar detection operation. Thus, even if a nearby reflective object is within range, grounding the T / R switch mimics a condition in which no reflected signal is being received. Configuring the T / R switch to null signals received via the antenna in this manner facilitates accurate identification and mitigation of interference from other sources, such as leakage.

[0058] Method 1000 may perform operation 1006, in which a signal may be transmitted using a transceiver of the wireless device. Similar to above, the signal may be a designated signal, e.g., a training signal, generated and transmitted through the transmit chain of the transceiver during a calibration phase. Thus, the training signal may have a known data pattern as well as one or more transmit parameters configured to mimic a signal used during radar detection operations.

[0059] Method 1000 may perform operation 1008, in which an input signal and an error signal may be provided to the adaptive filter. In various embodiments, the input signal is the signal transmitted during operation 1006. Thus, the input to the DAC of the transmit chain may also be provided as an input to the adaptive filter. Additionally, the output of the ADC of the receive chain may also be provided as an error signal to the adaptive filter.

[0060] Method 1000 may perform operation 1010, in which a plurality of weights may be determined based on the input signal and the error signal. Thus, similar to what was described above with reference to FIG. 4, one or more weights configured to control the operation of the adaptive filter may be adjusted until the weights converge such that the amplitude of the error signal falls below an acceptable threshold.

[0061] Method 1000 may perform operation 1012, in which the output of the adaptive filter may be provided before a low-pass filter. Similar to the above, the output of the adaptive filter may be combined before a low-pass filter included in a receive chain of the transceiver. Thus, during radar operation, the adaptive filter may perform an interference cancellation operation before the low-pass filter based on a plurality of weights.

[0062] 11 illustrates a further example of a method for interference cancellation performed in accordance with some embodiments. As described in more detail below, a method, e.g., method 1100, may perform additional calibration operations for various components, e.g., additional adaptive filters. In this manner, additional stages of interference cancellation may be performed.

[0063] Method 1100 may perform operation 1102, in which it may be determined that an interference cancellation operation should be performed. Similar to the above, this type of determination may be made dynamically and in response to interference signal detection. For example, interference signal detection may occur based on the output of a receive chain exceeding an acceptable threshold after an additional interference cancellation operation. In this manner, further stages of interference cancellation may be performed dynamically and downstream of a component, e.g., an LPF.

[0064] Method 1100 may perform operation 1104, in which the T / R switch of the wireless device may be grounded. Similar to the above, the T / R switch may be grounded to mimic the absence of a signal being received, such as when no object is present within range of radar detection operation. Configuring the T / R switch to null signals received via the antenna in this manner facilitates accurate identification and mitigation of interference from other sources, such as leakage.

[0065] Method 1100 may perform operation 1106, in which a signal may be transmitted using a transceiver of the wireless device. Similar to above, the signal may be a designated signal, e.g., a training signal, generated and transmitted through the transmit chain of the transceiver during a calibration phase. Thus, the training signal may have a known data pattern as well as one or more transmit parameters configured to mimic a signal used during radar detection operations.

[0066] Method 1100 may perform operation 1108, in which an input signal and an error signal may be provided to the adaptive filter. In various embodiments, the input signal is the signal transmitted during operation 1106. Thus, the input to the DAC of the transmit chain may also be provided as an input to the adaptive filter. Additionally, the output of the ADC of the receive chain may also be provided as an error signal to the adaptive filter.

[0067] Method 1100 may perform operation 1110, in which a plurality of weights may be determined based on the input signal and the error signal. Thus, similar to what was described above with reference to FIG. 5, one or more weights configured to control the operation of the adaptive filter may be adjusted until the weights converge such that the amplitude of the error signal falls below an acceptable threshold.

[0068] Method 1100 may perform operation 1112, in which the output of the adaptive filter may be provided after a low-pass filter. Similar to the above, the output of the adaptive filter may be coupled after an LPF included in a receive chain of the transceiver. Thus, during radar operation, the adaptive filter may perform an interference cancellation operation after the LPF based on multiple weights to further mitigate signal interference after the LPF. In this manner, multiple stages of interference cancellation may be implemented to achieve accurate and effective mitigation of interference that may result from leakage.

[0069] Although the above concepts have been described in some detail for clarity of understanding, it will be apparent that certain changes and modifications may be practiced within the scope of the appended claims. It should be noted that there are many alternative ways of implementing the processes, systems, and devices. Accordingly, the present examples should be considered illustrative and not limiting.

Claims

1. transmitting an input signal using a transmitter of a transceiver included in a wireless device; receiving an interference signal, the interference signal being a leakage signal, at a receiver of the transceiver; performing an interference cancellation operation on the interfering signal based at least in part on one or more adjustments of the receiver determined based on the input signal and the received interfering signal; generating, with the transceiver, an output signal based at least in part on the interference cancellation operation; A method comprising:

2. The step of performing an interference cancellation operation comprises: detecting the interfering signal using a received signal strength indicator (RSSI) detector; adjusting a voltage attenuator based at least in part on an output of the RSSI detector; adjusting a phase shifter based at least in part on an output of the receiver; further comprising: The method of claim 1.

3. the voltage attenuator and the phase shifter are coupled between the transmitter and the receiver of the transceiver; The method of claim 2.

4. The step of performing an interference cancellation operation comprises: adjusting a first adaptive filter based at least in part on the input signal and the output of the receiver; The method of claim 1.

5. the output of the first adaptive filter is provided to the receiver prior to a low pass filter included within the receiver; The method of claim 4.

6. The step of performing an interference cancellation operation comprises: adjusting a second adaptive filter based at least in part on the input signal and the output of the receiver. The method of claim 5.

7. the output of the second adaptive filter is provided to the receiver after the low pass filter included within the receiver; The method of claim 6.

8. the first adaptive filter and the second adaptive filter each comprise a least mean square filter. The method of claim 6.

9. the transceiver is compatible with a wireless communication protocol, and the transceiver is operating in a radar mode. The method of claim 1.

10. an antenna configured to transmit and receive wireless signals; a processing device comprising one or more processors configured to generate an input signal; A transceiver; a switch configured to couple the transceiver to the antenna; A system comprising: the transceiver comprises a transmitter configured to transmit the input signal received from the processing device; The transceiver further comprises a receiver, the receiver comprising: receiving an interference signal that is a leakage signal; performing an interference cancellation operation on the interfering signal based at least in part on one or more adjustments determined based on the input signal and the received interfering signal; generating an output signal based at least in part on the interference cancellation operation. system.

11. The system comprises: a received signal strength indicator (RSSI) detector configured to detect the interfering signal; a voltage attenuator configured to be adjusted based at least in part on the output of the RSSI detector; a phase shifter configured to be adjusted based at least in part on the output of the receiver; Further provided with The system of claim 10.

12. the voltage attenuator and the phase shifter are coupled between the transmitter and the receiver of the transceiver; The system of claim 11.

13. The system comprises: a first adaptive filter configured to be adjusted based at least in part on the input signal and the output signal generated by the receiver; The system of claim 10.

14. the output of the first adaptive filter is provided to the receiver prior to a low pass filter included within the receiver; The system of claim 13.

15. The system comprises: a second adaptive filter configured to be adjusted based at least in part on the input signal and the output signal generated by the receiver; the output of the second adaptive filter is provided to the receiver after the low pass filter included within the receiver; The system of claim 14.

16. one or more processors configured to generate an input signal; A transceiver; A device comprising: The transceiver includes: a transmitter configured to transmit the input signal; a receiver; Equipped with The receiver includes: receiving an interference signal that is a leakage signal; performing an interference cancellation operation on the interfering signal based at least in part on one or more adjustments determined based on the input signal and the received interfering signal; generating an output signal based at least in part on the interference cancellation operation. device.

17. The device comprises: a received signal strength indicator (RSSI) detector configured to detect the interfering signal; a voltage attenuator configured to be adjusted based at least in part on the output of the RSSI detector; a phase shifter configured to be adjusted based at least in part on the output of the receiver; Further provided with 17. The device of claim 16.

18. the voltage attenuator and the phase shifter are coupled between the transmitter and the receiver of the transceiver; 18. The device of claim 17.

19. the device further comprising a first adaptive filter configured to be adjusted based at least in part on the input signal and the output signal generated by the receiver; the output of the first adaptive filter is provided to the receiver prior to a low pass filter included within the receiver; 17. The device of claim 16.

20. the device further comprising a second adaptive filter configured to be adjusted based at least in part on the input signal and the output signal generated by the receiver; the output of the second adaptive filter is provided to the receiver after the low pass filter included within the receiver; 20. The device of claim 19.

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