A signal processing method, a UWB chip and an electronic device

Abstract

Embodiments of the present application relate to the technical field of UWB radar, and disclose a signal processing method, a UWB chip and electronic equipment. The signal processing method comprises: determining a first gain according to a UWB digital echo signal corresponding to a UWB analog echo signal received by a UWB radar in a time period other than a signal leakage time period; and performing gain adjustment on the received UWB analog echo signal according to the first gain and performing analog-digital conversion. The target detection effect of the UWB chip in the radar mode is improved.

Description

Technical Field

[0001] This application relates to the field of UWB technology, and in particular to a signal processing method, a UWB chip, and an electronic device. Background Technology

[0002] Ultra-wideband (UWB) chips are increasingly being used in smart homes, automobiles, and other fields because they can perform both data transmission and radar applications. One way UWB chips operate in radar mode is to first transmit a UWB detection signal, then receive the UWB echo signal reflected from the target, and use the transmission and reception times to achieve target detection.

[0003] However, the target detection performance of current UWB chips in radar mode needs improvement. Summary of the Invention

[0004] This application provides a signal processing method, a UWB chip, and an electronic device, which at least helps to improve the target detection performance of the UWB chip in radar mode.

[0005] According to some embodiments of this application, one aspect of this application provides a signal processing method, including: determining a first gain by detecting a portion of digital signals in a first UWB digital echo signal; wherein the first UWB digital echo signal is obtained by analog-to-digital conversion of a first UWB analog echo signal received by a UWB radar; the portion of digital signals is a portion of the first UWB digital echo signal within the corresponding echo period excluding the signal leakage period; and adjusting the gain of a subsequently received second UWB analog echo signal according to the first gain, and performing analog-to-digital conversion to output a second UWB digital echo signal.

[0006] According to some embodiments of this application, another aspect of this application provides a UWB chip, including: a transceiver circuit and a digital signal processing module connected in sequence; the transceiver circuit is used to transmit a UWB detection signal, and to receive a UWB analog echo signal and convert the received UWB analog echo signal into a UWB digital echo signal, and transmit it to the digital signal processing module; the digital signal processing module is used to determine a first gain by detecting a portion of the digital signal in the first UWB digital echo signal, and to adjust the receiving circuit in the transceiver circuit according to the first gain; wherein, the first UWB digital echo signal is obtained by analog-to-digital conversion of the first UWB analog echo signal received by the receiving circuit; the portion of the digital signal is the time period portion of the first UWB digital echo signal within the corresponding echo period excluding the signal leakage period; the transceiver circuit is further used to adjust the gain of a subsequently received second UWB analog echo signal according to the first gain, and to perform analog-to-digital conversion to output the second UWB digital echo signal.

[0007] According to some embodiments of this application, another aspect of this application provides an electronic device, including: a carrier; an integrated circuit as described in any embodiment of this application, disposed on the carrier; an antenna, disposed on the carrier, or the antenna and the integrated circuit are integrated into a single device disposed on the carrier; wherein the integrated circuit is connected to the antenna and is used for target detection and / or communication to provide reference information to the operation of the device body.

[0008] The technical solution provided in this application has at least the following advantages:

[0009] The first gain is determined by analyzing the UWB digital echo signals corresponding to the UWB analog echo signals received by the UWB radar outside the signal leakage period, rather than by determining the gain based on the UWB digital echo signals corresponding to all UWB analog echo signals received by the UWB radar. This eliminates the influence of the leakage signal during the determination of the first gain, avoiding the adverse effects of signal leakage in the UWB chip on the first gain and improving its accuracy. Therefore, adjusting the gain of the received UWB analog echo signals based on the first gain is more in line with the dynamic range of the analog-to-digital converter (ADC). This allows the gain-adjusted signal to obtain more sampling points through the ADC's analog-to-digital conversion function, enabling more comprehensive and accurate target detection and improving the target detection performance of the UWB chip in radar mode. Attached Figure Description

[0010] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0011] Figure 1 This is a schematic diagram of the structure of a UWB radar;

[0012] Figure 2 This is a flowchart of the signal processing method provided in the embodiments of this application. Figure 1 ;

[0013] Figure 3 This is a flowchart of the signal processing method provided in the embodiments of this application. Figure 2 ;

[0014] Figure 4 This is a flowchart of the signal processing method provided in the embodiments of this application. Figure 3 ;

[0015] Figure 5 This is a schematic diagram showing the correspondence between the pulse signal involved in the signal processing method provided in the embodiments of this application and the gain used when adjusting the gain;

[0016] Figure 6 This is a flowchart of the signal processing method provided in the embodiments of this application. Figure 4 ;

[0017] Figure 7 This is a flowchart of the signal processing method provided in the embodiments of this application. Figure 5 ;

[0018] Figure 8 This is a flowchart of the signal processing method provided in the embodiments of this application. Figure 6 ;

[0019] Figure 9 This is a schematic diagram of the structure of the preamble symbol involved in the signal processing method provided in the embodiments of this application;

[0020] Figure 10 This is a schematic diagram of the structure of the UWB chip provided in the embodiments of this application. Detailed Implementation

[0021] As can be seen from the background technology, the target detection performance of current UWB chips in radar mode needs to be improved.

[0022] Analysis revealed that the aforementioned problem stems from at least the following reasons: The UWB chip possesses a radar mode; in radar mode, the UWB chip is simply referred to as UWB radar. Some UWB radars have structures such as... Figure 1As shown, the system includes a radio frequency (RF) module and a digital signal processing module. Specifically, the RF module includes a transmitting circuit that sends a UWB detection signal to free space via a switching module and an antenna. The UWB detection signal is reflected by an object to form a UWB echo signal, which is received by the antenna to form a UWB analog echo signal. The UWB analog echo signal is down-mixed by the RF receiving circuit and transmitted to an automatic gain control (AGC) module and an analog-to-digital converter (ADC) to output a UWB digital echo signal. The digital signal processing module (e.g., a digital signal processing (DSP) chip or dedicated digital circuitry) performs digital signal processing to provide point cloud data for target detection.

[0023] In this example, because the UWB radar uses a shared antenna for both transmission and reception, and transmits and receives simultaneously, the transmitted UWB detection signal will directly leak to the receiver, thus interfering with the UWB analog echo signal.

[0024] This signal leakage also exists in other UWB radar examples that provide separate transmitting and receiving antennas. For example, the UWB transmitting and receiving antennas are close together. For instance, echo signals reflected from very close objects such as vehicle bumpers may also be considered signal leakage.

[0025] Based on the above analysis, because the leakage location of the UWB detection signal is very close to the UWB radar receiving circuit, it will be received earlier than the echo signal reflected back from the external target. That is, the first pulse signal in the UWB analog echo signal received by the UWB radar between the start of one UWB detection signal transmission and the start of the next UWB detection signal transmission may be formed by the leakage of the UWB detection signal. In other words, the interference caused by the leakage signal of the UWB detection signal is usually reflected within the echo period of the UWB radar. The echo period refers to the time between the start of one UWB detection signal transmission and the start of the next UWB detection signal transmission.

[0026] When setting the gain, the AGC module typically determines the gain based on the signal with the strongest signal strength. This causes the AGC gain value to be determined according to the portion of the digital signal corresponding to the leaked signal (also known as the second sub-signal). Consequently, in the UWB digital echo signals received within the same echo period, the signal strength of the second sub-signal corresponding to the signal leakage period is significantly greater than the signal strength of the first sub-signal outside the signal leakage period. In this case, the first sub-signal in the received signal adjusted using the AGC module configured with the second gain will be too small, resulting in signals that fail to reach the minimum threshold of the dynamic range supported by the ADC. These signals are easily masked by the noise floor, leading to the loss of certain targets in subsequent processing.

[0027] To address the aforementioned issues, this application provides a signal processing method, a UWB chip, and an electronic device. To avoid the adverse effects of signal leakage, when determining the usable first gain, the UWB digital echo signal portion corresponding to the signal leakage period is removed. Instead, the UWB digital echo signal corresponding to the UWB analog echo signal received by the UWB radar during periods outside the signal leakage period is used for determination. This eliminates the adverse effects of signal leakage in the UWB chip on the first gain, improving its accuracy. Therefore, the UWB analog echo signal adjusted according to the first gain will better match the dynamic range of the analog-to-digital converter (ADC). The gain-adjusted signal can then obtain more sampling points through the ADC's analog-to-digital conversion function, enabling more comprehensive and accurate target detection and improving the target detection performance of the UWB chip in radar mode.

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the various embodiments of this application will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of this application to enable readers to better understand this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0029] The division of the following embodiments is for ease of description and should not constitute any limitation on the specific implementation of this application. The various embodiments can be combined with and referenced by each other without contradiction.

[0030] This application provides a signal processing method that includes adjusting the gain of the received signal using a preset gain as an initial value and adjusting the AGC gain (also known as the gain threshold) based on digital domain analysis of the received signal in some AGC strategies for UWB radar. These methods adjust the gain of all received signals during UWB radar operation, thereby reducing interference from abnormally high-energy signals, including leakage signals, to UWB radar target identification. The AGC strategy provided in this application aims to adjust the gain in a way that is more conducive to identifying targets from UWB analog echo signals.

[0031] For ease of description, the received signal processed by the UWB radar receiver during an echo period is divided into a first sub-signal and a second sub-signal. The first sub-signal represents the portion of the received signal that is not interfered with by leaked signals during the echo period. The second sub-signal is complementary to the first sub-signal to form all the received signals received during the echo period.

[0032] As mentioned earlier, during the period from the start of one UWB detection signal transmission to the start of the next UWB detection signal transmission—that is, within a complete echo period—some pulse signals in the UWB analog echo signals received by the UWB radar may be assumed, or, when the energy is abnormally high, identified as leaked signals from the UWB detection signal. For example, the first pulse signal may be a signal interfered with by the UWB detection signal, while the other signals may be signals not interfered with by the UWB detection signal.

[0033] To select a gain threshold that is more conducive to target detection in AGC, the UWB radar determines a first gain by analyzing a portion of the digital signal in a first UWB digital echo signal received during at least one echo period in the digital domain; and uses the first gain to adjust the subsequently received second UWB analog echo signal. The first UWB digital echo signal is obtained by analog-to-digital conversion of the first UWB analog echo signal received by the UWB radar; the portion of the digital signal is a portion of the first UWB digital echo signal within the corresponding echo period, excluding the signal leakage period.

[0034] It should be noted that when the AGC gain threshold is adjusted to the first gain within an echo period, the portion of the UWB analog echo signal received by the UWB device within the same echo period, before the gain threshold is adjusted, is referred to as the first UWB analog echo signal; the portion of the UWB analog echo signal received by the UWB device within the same echo period, after the gain threshold is adjusted, is referred to as the second UWB analog echo signal; and in subsequent echo periods, if the AGC gain threshold remains at the first gain or the set gain threshold is updated according to the examples below, the UWB analog echo signal received by the UWB device is referred to as the second UWB analog echo signal.

[0035] When the gain threshold of the AGC is adjusted to the first gain after one echo period, and in subsequent echo periods the gain threshold of the AGC remains at the first gain or the set gain threshold is updated in the manner described in the examples below, the UWB analog echo signal received by the UWB device is referred to as the second UWB analog echo signal.

[0036] One embodiment of this application provides a signal processing method, the flow of which is as follows: Figure 2 As shown, it includes the following steps:

[0037] Step 201: Determine the first gain by detecting a portion of the digital signal in the first UWB digital echo signal.

[0038] Step 202: Based on the first gain, adjust the gain of the subsequently received second UWB analog echo signal and perform analog-to-digital conversion to output the second UWB digital echo signal.

[0039] In this way, the first gain is determined based on the portion of the digital signal corresponding to the period outside the signal leakage period of the first UWB digital echo signal during the echo period. This avoids the adverse effects of signal leakage in the UWB chip on the selection of the first gain, improves the accuracy of the first gain, and enables the gain adjustment of the subsequently received second UWB analog echo signal based on the first gain to not only conform to the dynamic range of the analog-to-digital converter, but also to obtain more sampling points through the analog-to-digital conversion function of the analog-to-digital converter after gain adjustment. This further increases the signal-to-noise ratio representing the target, which is beneficial for target detection and improves the target detection effect of the UWB chip in radar mode.

[0040] To facilitate a better understanding of the above embodiments by those skilled in the art, they will be explained and described below.

[0041] Regarding step 201, as mentioned earlier, signal leakage could be due to leakage of the UWB probe signal, reflection from a nearby terminal device, or both. Regardless of the cause, the signal strength of the leaked signal is significantly greater than that of other normal UWB analog echo signals. Therefore, in some embodiments, the signal leakage period is the time period occupied by the abnormally energetic UWB analog echo signal received in each transmission cycle, or a fixed time period. Here, the transmission cycle refers to the period from the start of one UWB probe signal transmission to the start of the next UWB probe signal transmission, which is also the echo cycle.

[0042] For example, the leaked signal is the first pulse signal received by the UWB radar during the echo period. The time period occupied by the first pulse signal received by the UWB radar is considered the signal leakage period.

[0043] For example, the leakage period occupied by the leaked signal is the same period occupied by the UWB radar transmitting the UWB detection signal.

[0044] Of course, the above is only an illustrative explanation of the signal leakage period and does not mean that the signal leakage period can only be the period defined above. In some embodiments, the signal leakage period can also be the time period occupied by the UWB radar transmitting the UWB detection signal plus a certain duration after the UWB radar completes each transmission of the UWB detection signal, etc. This further extends the duration of the signal leakage period, making it possible to better eliminate interference caused by signal leakage outside of transmission, which is beneficial to further improving the target detection effect of the UWB chip.

[0045] Furthermore, the reception, gain adjustment, and analog-to-digital conversion of UWB analog echo signals occur continuously. This means that the UWB digital echo signal output by the analog-to-digital converter is not differentiated based on whether it belongs to the UWB analog echo signal received during a signal leakage period. Therefore, the signal leakage period can be determined according to its definition, thereby identifying the corresponding UWB analog echo signal portion (also known as the second sub-signal) and excluding the UWB analog echo signal portion (also known as the first sub-signal) received by the UWB radar during the period outside the signal leakage period. Alternatively, the signal leakage period can be determined according to its definition, thereby identifying the period outside the signal leakage period and thus obtaining the corresponding UWB digital echo signal portion of the UWB analog echo signal received by the UWB radar during the period outside the signal leakage period.

[0046] The aforementioned signal leakage periods can be determined by detecting the leaked signal. For example, detection can reveal the time period occupied by the first pulse signal in the first UWB analog echo signal received by the UWB radar during the entire echo period. Alternatively, detection can reveal the time period occupied by the pulse signal with abnormally high signal strength in the first UWB analog echo signal received by the UWB radar during the entire echo period.

[0047] In some embodiments, such as Figure 3 As shown, the method for detecting leakage signals includes the following steps:

[0048] Step 301: During a complete echo period, detect the received first UWB digital echo signal to obtain the leakage signal and its leakage period.

[0049] In this embodiment, the gain threshold of AGC is a preset initial value or a second gain before determining the first gain. The first UWB analog echo signal is converted from analog to digital to obtain the first UWB digital echo signal. The second gain is determined based on the UWB analog echo signals received by the UWB radar during the signal leakage period or the entire echo period.

[0050] UWB devices identify leakage signals and their leakage periods by performing power spectrum analysis on a first UWB digital echo signal obtained within at least one echo period. Specifically, the location of the power peak of the leakage signal in the power-time distribution of the first digital echo signal is used to determine the leakage signal and its leakage period. The power-time distribution can be represented by a power-distance distribution. Considering the spectral extension effect of the leakage signal, in some embodiments, the leakage period may also be determined by combining the location of the power peak of the leakage signal with the signal spectral width.

[0051] For example, by analyzing the power spectrum, the main frequency, extended frequency, peak power, time (or distance) location, signal-to-noise ratio, and differences between multiple power peaks of the reflected UWB echo signal and leakage signal contained in the first UWB digital echo signal can be obtained.

[0052] By utilizing the power spectrum analysis described above to detect the signal characteristics of the leakage signal, a portion of the digital signal corresponding to the leakage period in the first digital echo signal can be deduced. Examples of such signal characteristics include: the first pulse signal, signal strength exceeding a preset abnormal threshold, a fixed signal position among multiple first UWB digital echo signals, and a frequency range that matches the transmitted UWB detection signal.

[0053] Step 302: Determine the first gain based on the portion of the digital signal in the first UWB digital echo signal excluding the leakage signal.

[0054] Here, similar to the method used to determine the first gain in step 201, the digital signal portion of the first UWB digital echo signal excluding the leakage signal, i.e., the first sub-digital signal corresponding to the first sub-signal, includes signal characteristics obtained by the UWB detection signal reflected from the target. Examples include at least one of the following: signal strength above the signal noise floor, a spectral range consistent with the UWB detection signal, and the signal power peak located within the effective detection area of ​​the UWB radar. The effective detection area is the region within the maximum detection range of the UWB radar, excluding the detection blind zone corresponding to the leakage signal period.

[0055] A first gain is determined based on the signal characteristics reflecting the target identified in the first sub-digital signal. Here, since the first gain is set based on a power peak value lower than that of the leakage signal, it is less than the aforementioned second gain.

[0056] The determined first gain can be updated to the AGC during the current echo period or after the current echo period ends, so that the second UWB analog echo signal subsequently received by the UWB radar is processed by the AGC and fed into the ADC to output the corresponding second digital echo signal. In other words, after the UWB radar determines the first gain, it feeds it back to the AGC in the UWB receiving circuit to receive subsequent UWB analog echo signals. For example, as Figure 5 As shown, the first M UWB analog echo signals (symbols) received by the UWB radar are down-mixed to intermediate frequency (IF). The AGC uses a second gain to adjust the gain of the received IF UWB analog echo signals, thereby determining the first gain through steps such as 301 described above, and adjusting the gain threshold in the AGC. Starting from the (M+1)th UWB analog echo signal, the AGC uses the first gain to adjust the gain of the received IF UWB analog echo signals.

[0057] The following example illustrates the difference in gain processing for UWB analog echo signals using the second gain and the first gain:

[0058] Taking the period between the start of one UWB detection signal transmission and the start of the next UWB detection signal transmission, the time period occupied by the first pulse signal received by the UWB radar is taken as the signal leakage period. Assume that two first UWB digital echo signals are acquired within two consecutive echo periods T1 and T2, where both first UWB digital echo signals are obtained by processing the signals received by the UWB radar through an AGC configured with a second gain and performing analog-to-digital conversion. According to any of the aforementioned examples, the signal leakage period is confirmed to be the time period occupied by signals a1 and a2. The periods outside the respective signal leakage periods of echo periods T1 and T2 respectively illustrate the characteristics of the echo signals received after the UWB detection signals are reflected from external targets, namely signals b1 and c1, and signals b2 and c2.

[0059] When the UWB device determines the first gain and updates it to the AGC based on signal b1 during the echo period T1, signal c1 is a portion of the digital signal in the second digital echo signal processed and digitized according to the AGC configured with the first gain. The portion of the digital signal in the second UWB digital echo signal corresponding to the signal leakage period during the echo period T2 is a saturated signal.

[0060] When the UWB device determines the first gain based on signal b1 during the echo period T1 and updates it to AGC after the echo period ends, then signals b2 and c2 during the echo period T2 are partial digital signals in the second digital echo signal processed and digitized according to the AGC configured with the first gain. Therefore, the partial digital signal in the second UWB digital echo signal corresponding to the signal leakage period during the echo period T2 is a saturated signal.

[0061] Because the first gain is less than the second gain, the leaked signal will be skewed based on the first gain. This means the gain adjustment of the UWB analog echo signal received by the UWB radar during the signal leakage period is insufficient, leading to signal saturation. In other words, in some embodiments, the digital signal corresponding to the UWB analog echo signal received during the signal leakage period will appear as a saturated signal. At this time, during analog-to-digital conversion, a portion of the saturated signal will be unsampled because it exceeds the dynamic range of the analog-to-digital converter. Furthermore, this portion of the signal is interfered with by the leaked signal, resulting in low detection accuracy. Therefore, in some embodiments, this portion can be removed.

[0062] For example, in some embodiments, such as Figure 4 As shown, the signal processing method includes the following steps:

[0063] Step 401: Determine the first gain based on a portion of the digital signal in the first UWB digital echo signal, excluding the signal leakage period.

[0064] Step 402: Adjust the gain of the received second UWB analog echo signal according to the first gain, and perform analog-to-digital conversion to output the second UWB digital echo signal.

[0065] Step 403: Remove a portion of the digital signal during the signal leakage period from the second UWB digital echo signal.

[0066] There are several methods for signal removal. For example, as mentioned earlier, the signal leakage period can be determined, so all signals corresponding to the leakage period can be directly removed. Furthermore, as mentioned earlier, the digital signal corresponding to the UWB analog echo signal received during the leakage period will also exhibit saturation. Therefore, saturation signals can also be removed from the analog-to-digital conversion result, or saturation signals and their extensions can be removed. A saturation signal is the signal corresponding to the region where saturation occurs. The extension of the saturation signal, considering the signal's extension and continuity, means that a portion of the signal corresponding to the leakage period will still be sampled within the dynamic range of the analog-to-digital converter. This extension is the saturation signal's extension. Therefore, removing the non-saturated portion of the pulse signal containing the saturation signal reduces the wasted resources in subsequent target detection processing of saturation signals and their extensions, improving resource utilization and the real-time performance of target detection.

[0067] Thus, based on other embodiments, by removing a portion of the signal from the UWB analog echo signal after gain adjustment according to the first gain, subsequent target detection avoids wasting resources processing unreliable signals, thereby improving resource utilization and the real-time performance of target detection.

[0068] Considering that saturation signals may affect the normal operation of some components in the receiving circuit, this application also provides a method to avoid signal leakage periods by delaying the connection of the UWB radar receiving circuit. In this way, the AGC in the receiving circuit adjusts the gain of the second UWB analog echo signal received by the connected receiving circuit according to a first gain, and performs analog-to-digital conversion.

[0069] For example, in some embodiments, the receiving circuitry of a UWB radar includes a radio frequency receiving circuit, a gain adjustment module (AGC), and an analog-to-digital converter (ADC). Figure 6 As shown, the signal processing method includes the following steps:

[0070] Step 601: Determine the first gain based on the portion of the digital signal in the first UWB digital echo signal excluding the signal leakage period.

[0071] Step 602: During the signal leakage period, shut down devices in the receiving circuit that are prone to rapid response to prevent the leaked signal from being converted into a digital signal. Examples of devices that are prone to rapid response include: AGC, LNA in the RF receiving circuit, or devices in the receiving circuit that can respond quickly, such as switches and bias circuits.

[0072] Step 603: During the period outside the signal leakage period, the receiving circuit is operated to adjust the gain of the received second UWB analog echo signal according to the first gain and perform analog-to-digital conversion.

[0073] In this way, by turning off the gain receiving circuit during the signal leakage period, the interfered signal does not need to be processed during the digital signal processing stage, thus avoiding the tedious process of subsequent signal removal.

[0074] It should be noted that in the above embodiments, regardless of whether signal removal or partial module shutdown is used, some blind spots will occur due to the lack of sampling points for the corresponding time period. For example, if 6 sampling points in the second UWB digital echo signal are missing, then at a sampling rate of 1 GHz, the range of the blind spot generated by target detection is 0 to 0.9 meters (where 6ns * 0.3 / 2 = 0.9 meters). Therefore, a signal with a spectrum within 500MHz and a fast attenuation of time-domain energy after 2ns should be selected as the UWB detection signal transmitted by the UWB radar to reduce the number of sampling points subsequently removed, thereby reducing the blind spot.

[0075] Therefore, the effective detection range of the second UWB digital echo signal is (d, D). Here, d is the distance corresponding to the duration of leakage of the UWB detection signal to the UWB analog echo signal, and D is the maximum detection range of the UWB radar. The maximum detection range of the UWB radar can be the nominal detection range of the UWB radar, or the desired detection range when applying the UWB radar, etc. For example, the echo period is set based on the maximum detection range of the UWB radar.

[0076] To prevent the echo received by the UWB radar during the i-th echo period from being reflected by a near target from being superimposed with the echo signal received during the (i-1)-th echo period from being reflected by a distant target, thus reducing the accuracy of target detection, in some embodiments, the echo period set by the UWB radar, i.e., the transmission interval of the UWB detection signal, is not less than the minimum transmission interval: T = (2*S) / 0.3; where T is the minimum transmission interval and S is the maximum detection range of the UWB radar.

[0077] Taking the configuration of the transmission interval of the aforementioned UWB probe signal through a UWB preamble symbol as an example, the structure of the preamble symbol is as follows: Figure 9 As shown, a certain number of idle times (chips) (delta length) are indicated after each UWB analog echo signal (pulse) Ci(k) (k=0,1,……,L-1), with each chip corresponding to a duration of 2ns (nanoseconds).

[0078] In other words, the delta length indicated in the preamble symbol needs to satisfy the following condition: the corresponding signal transmission interval is not less than the aforementioned minimum transmission interval. That is, a larger delta length can be selected. In this way, a relatively large gap is left between one UWB detection signal and the next UWB detection signal, which can avoid the aliasing of the echo signal received by the UWB radar with the signal it transmits.

[0079] For example, if the UWB radar is expected to detect at a distance of 9 meters, then the minimum transmission interval of the UWB detection signal is: 2*9 / 0.3=60ns, which is equivalent to 30 chips, i.e., the delta length is 30.

[0080] In some embodiments, when the UWB radar is expected to detect a distance of 9 meters, the delta length is greater than 32; similarly, to detect a distance of 18 meters, the delta length is greater than 64 chips.

[0081] The first gain mentioned in this application can also be dynamically adjusted. Based on this, such as Figure 7 As shown, in some embodiments, the signal processing method includes the following steps:

[0082] Step 701: Determine the first gain based on a portion of the digital signal in the first UWB digital echo signal, excluding the signal leakage period.

[0083] Step 702: Adjust the gain of the received second UWB analog echo signal according to the first gain, and perform analog-to-digital conversion.

[0084] Step 703: Update the first gain based on the power spectrum of the second UWB digital echo signal.

[0085] In this embodiment, the peak signal strength of the effective detection range in the second UWB digital echo signal is detected, and the first gain is adjusted based on the maximum value of the peak signal strength. The gain configuration of AGC is updated using a feedback mechanism until UWB radar detection terminates.

[0086] In this way, based on other embodiments, the second UWB digital echo signal outside the signal leakage period can be continuously updated according to the result of analog-to-digital conversion, and the first gain can be continuously updated so that the first gain can adapt to the scenario where the relative distance and angle between the target and the UWB radar are constantly changing, and better match the subsequently received second UWB analog echo signal, thereby further improving the gain adjustment effect and thus improving the effect of subsequent target detection.

[0087] During the signal leakage period, the signal processed by AGC with the first gain is prone to saturation, resulting in a detection blind zone in the corresponding detection area. Delaying the activation of the receiving circuit also creates a detection blind zone. To reduce the detection blind zone and improve the detection efficiency of UWB radar, this application can further employ a second gain and a first gain to receive different signal portions of the second UWB analog echo signal during the signal leakage and non-signal leakage periods within an echo period. For example, a fast-response circuit in the receiving circuit can be used to quickly switch between the first and second gains, reducing the impact of blind zones caused by the switching operation.

[0088] For example, such as Figure 8 As shown, the signal processing method includes the following steps:

[0089] Step 801: Determine the first gain based on a portion of the digital signal in the first UWB digital echo signal during at least one echo period, corresponding to the time period other than the signal leakage period.

[0090] Step 802: During the signal leakage period in the subsequent echo period, adjust the signal gain according to the second gain to output the first UWB analog echo signal, and perform analog-to-digital conversion. The second gain is determined based on the first UWB analog echo signal received by the UWB radar during the signal leakage period or all periods.

[0091] Step 803: Outside the signal leakage period during the subsequent echo period, adjust the signal gain according to the first gain to output the second UWB analog echo signal, and perform analog-to-digital conversion.

[0092] In other words, using the appropriate gain for signal processing at different time periods improves the accuracy of signal processing and helps to improve the target detection effect.

[0093] For example, when performing target detection using the above method, the UWB digital echo signal received during a complete echo period includes a portion of the digital signal processed by AGC configured with a second gain, which is then processed to obtain the Channel Impulse Response (CIR) CIR1, and another portion of the digital signal processed by AGC configured with a second gain, which is then processed to obtain the Channel Impulse Response (CIR2). By performing target analysis processing on CIR1+CIR2, a complete and comprehensive detection result of the UWB radar for target detection can be obtained. Here, CIR1 represents the signal characteristics formed by the reflection of the UWB detection signal from a nearby target, and CIR2 represents the signal characteristics formed by the reflection of the UWB detection signal from a distant target.

[0094] The steps of the various methods described above are only for clarity. In practice, they can be combined into one step or some steps can be split into multiple steps. As long as they include the same logical relationship, they are all within the scope of protection of this patent. Adding insignificant modifications or introducing insignificant designs to the algorithm or process, but without changing the core design of the algorithm and process, are also within the scope of protection of this patent.

[0095] Another aspect of this application embodiment also provides a UWB chip, such as... Figure 10 As shown, the transceiver circuit includes a transceiver circuit 1001 and a digital signal processing module 1002 connected in sequence. The transceiver circuit is used to transmit a UWB detection signal and receive a UWB analog echo signal, convert the received UWB analog echo signal into a UWB digital echo signal, and transmit it to the digital signal processing module. The digital signal processing module is used to determine a first gain by detecting a portion of the digital signal in the first UWB digital echo signal, and adjust the receiving circuit in the transceiver circuit according to the first gain. The first UWB digital echo signal is obtained by analog-to-digital conversion of the first UWB analog echo signal received by the receiving circuit. The portion of the digital signal is the time period in the first UWB digital echo signal excluding the signal leakage period within the corresponding echo period. The transceiver circuit is also used to adjust the gain of the subsequently received second UWB analog echo signal according to the first gain and perform analog-to-digital conversion to output the second UWB digital echo signal.

[0096] The transceiver circuit includes a transmitting circuit and a receiving circuit for transmitting and receiving UWB signals, respectively. The receiving circuit within the transceiver circuit includes a radio frequency receiving circuit, an adjustable gain controller (AGC), and an analog-to-digital converter (ADC). A digital signal processing module is connected to the AGC to change its gain threshold. In this application, the digital signal processing module can change the AGC's gain threshold to a first gain or a second gain, or update the first gain, etc.

[0097] The digital signal processing module works in coordination with the AGC in the transceiver circuit, enabling the UWB chip to improve its target detection capability when in radar mode.

[0098] Another embodiment of this application relates to an electronic device, comprising: a carrier, the aforementioned integrated circuit disposed on the carrier, and an antenna disposed on the carrier, or the antenna and integrated circuit integrated into a single device disposed on the carrier. The integrated circuit is connected to the antenna and is used to transmit UWB detection signals externally and / or receive UWB analog echo signals from external sources.

[0099] When the antenna and integrated circuit are not integrated into a single device, the integrated circuit is connected to the antenna via a first transmission line, which can be a printed circuit board (PCB) trace. The carrier can be a printed circuit board (PCB), such as a development board, data acquisition board, or the motherboard of a device, etc., which will not be elaborated on here.

[0100] Since the structure and working principle of the integrated circuits included in the electronic device have been described in detail in the above embodiments, they will not be repeated here.

[0101] The electronic device can be installed in a terminal device. The terminal device may include: a device body; and an electronic device as described above installed on the device body; wherein the electronic device is used for target detection to provide reference information to the operation of the device body.

[0102] In some embodiments, the electronic device may be disposed outside the device body; in other embodiments, the electronic device may be disposed inside the device body; and in still other embodiments, the electronic device may be partially disposed inside the device body and partially disposed outside the device body. This application does not limit the scope of the embodiments; the specific method depends on the circumstances.

[0103] It should be noted that electronic devices can achieve functions such as target detection by transmitting and receiving radio signals, providing measurement information of the detected target to the device itself, thereby assisting or even controlling the operation of the device. Examples of measurement information include at least one of relative distance, relative speed, and relative angle.

[0104] In some embodiments, the device body described above can be a component or product applied in fields such as transportation, consumer electronics, monitoring, in-cabin detection, and healthcare. For example, the device body can be intelligent transportation equipment (such as automobiles, motorcycles, ships, subways, trains, etc.), security equipment (such as cameras), liquid level / flow rate detection equipment, smart wearable devices (such as wristbands, glasses, etc.), smart home devices (such as robot vacuum cleaners, door locks, televisions, air conditioners, smart lights, etc.), various communication devices (such as mobile phones, tablets, etc.), as well as devices such as barriers, intelligent traffic lights, intelligent signs, traffic cameras, and various industrial robotic arms (or robots). It can also be various instruments used to detect vital signs parameters and various devices equipped with such instruments, such as in-cabin detection in automobiles, indoor personnel monitoring, intelligent medical devices, and consumer electronic devices.

[0105] In some embodiments, when the aforementioned device body is applied to an Advanced Driving Assistance System (ADAS), the electronic device, as an on-board sensor, can provide various functional safety guarantees for the ADAS system, such as Automatic Emergency Braking (AEB), Blind Spot Detection (BSD), Lane Changing Assist (LCA), and Rear CrossTraffic Alert (RCTA).

[0106] Furthermore, the examples mentioned in the above embodiments can be freely combined, and any combination can be understood as an embodiment. The terms "embodiment" or "example" appearing in various locations in the specification do not necessarily refer to the same embodiment, nor are they independent or alternative embodiments mutually exclusive with other embodiments. Those skilled in the art will understand that the embodiments described herein can be combined with other embodiments.

[0107] Those skilled in the art will understand that the above embodiments are specific embodiments for implementing this application, and in practical applications, various changes can be made to them in form and detail without departing from the spirit and scope of this application.

Claims

1. A signal processing method, characterized in that, include: A first gain is determined by detecting a portion of the digital signal in the first UWB digital echo signal; wherein the first UWB digital echo signal is obtained by analog-to-digital conversion of the first UWB analog echo signal received by the UWB radar; and the portion of the digital signal is a portion of the first UWB digital echo signal within the corresponding echo period, excluding the signal leakage period. Based on the first gain, the gain of the subsequently received second UWB analog echo signal is adjusted and analog-to-digital conversion is performed to output the second UWB digital echo signal.

2. The signal processing method according to claim 1, characterized in that, The step of adjusting the gain of subsequently received UWB analog echo signals based on the first gain and performing analog-to-digital conversion includes: Based on the first gain, the gain of the second UWB analog echo signal received during the entire subsequent echo period is adjusted and analog-to-digital converted to output the second UWB digital echo signal.

3. The signal processing method according to claim 1, characterized in that, The method further includes: Target detection is performed using a portion of the digital signal from the second UWB digital echo signal, excluding the signal leakage period.

4. The signal processing method according to claim 3, characterized in that, The portion of the digital signal corresponding to the signal leakage period in the second UWB digital echo signal is a saturated signal.

5. The signal processing method according to claim 1, characterized in that, The step of adjusting the gain of the received second UWB analog echo signal according to the first gain and performing analog-to-digital conversion includes: Delaying the connection of the UWB radar's receiving circuit to avoid periods of signal leakage; or During the signal leakage period and non-signal leakage period within an echo period, different signal portions of the second UWB analog echo signal are received using the second gain and the first gain, respectively.

6. The signal processing method according to claim 1, characterized in that, The effective detection range of the second UWB digital echo signal is (d, D), where d is the signal transmission distance corresponding to 0.5 * the signal leakage time, and D is the farthest detection distance of the UWB radar.

7. The signal processing method according to claim 1, characterized in that, The first gain is less than the second gain, wherein the second gain is determined based on the UWB analog echo signal received by the UWB radar during the signal leakage period or the entire echo period.

8. The signal processing method according to claim 1, characterized in that, The signal leakage period includes: the period occupied by the first pulse signal in the first UWB analog echo signal received by the UWB radar during the entire echo period; or, the signal leakage period includes the period occupied by the UWB radar transmitting the UWB detection signal; or, the period occupied by the pulse signal with abnormally high signal strength in the first UWB analog echo signal received by the UWB radar during the entire echo period.

9. The signal processing method according to any one of claims 1 to 6, characterized in that, Also includes: The first gain is updated based on the power spectrum of the second UWB digital echo signal.

10. The signal processing method according to claim 5, characterized in that, The second gain is a preset value or is detected based on the power spectrum of a portion of the signal during the signal leakage period in any UWB analog echo signal.

11. The signal processing method according to any one of claims 1 to 6, characterized in that, The echo period is not shorter than: T = (2*S) / 0.3; Where T is the echo period and S is the maximum detection range of the UWB radar.

12. The signal processing method according to claim 1, characterized in that, Also includes: During a complete echo period, the first received UWB digital echo signal is detected to obtain the leakage signal and its leakage period. The first gain is determined based on the portion of the digital signal other than the leaked signal in the first UWB digital echo signal.

13. A UWB chip, characterized in that, include: The transceiver circuit and the digital signal processing module are connected in sequence. The transceiver circuit is used to transmit UWB detection signals, and to receive UWB analog echo signals and convert the received UWB analog echo signals into UWB digital echo signals, and transmit them to the digital signal processing module. The digital signal processing module is used to determine a first gain by detecting a portion of the digital signal in the first UWB digital echo signal, and adjust the receiving circuit in the transceiver circuit according to the first gain; wherein, the first UWB digital echo signal is obtained by analog-to-digital conversion of the first UWB analog echo signal received by the receiving circuit; the portion of the digital signal is the time period in the first UWB digital echo signal excluding the signal leakage period within the corresponding echo period; The transceiver circuit is also used to adjust the gain of the subsequently received second UWB analog echo signal according to the first gain, and to perform analog-to-digital conversion to output the second UWB digital echo signal.

14. An electronic device, characterized in that, include: Carrier; The UWB chip as described in claim 13 is disposed on the carrier. An antenna is disposed on the carrier, or the antenna and the integrated circuit are integrated into a single device and disposed on the carrier. The integrated circuit is connected to the antenna and is used for target detection and / or communication.

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