Interference suppression engine

Abstract

An integrated circuit is described. The integrated circuit may include a plurality of stages. At a given time, the integrated circuit may be configured to use one or more of the stages in processing received signals associated with measurements in the environment. For example, a control circuit or control logic in the integrated circuit may configure use of one or more of the stages in the integrated circuit. A first of the stages may perform coherent interference suppression by correcting the received signal for a predicted complex signal associated with a spurious source. Further, a second one of the stages may perform equalization of the received signal based at least in part on a target criterion. Further, a third of the stages may combine different received signals, such as received signals associated with different measurements, and may detect one or more peaks in the received signals.

Description

Technical Field

[0001] This disclosure relates to techniques for suppressing interference associated with wireless and / or optical measurements. For example, these techniques can suppress interference associated with radar or lidar. Background Technology

[0002] Wireless and optical measurements in the environment are often distorted by interference sources. However, compensating for or correcting different interference sources can be complex and expensive.

[0003] For example, radio detection and ranging (radar) uses electromagnetic waves or beams to measure the relative position and / or velocity of one or more objects in the environment, such as around a vehicle. Due to the width of the electromagnetic waves or beams in radar, radar measurements often contain a lot of clutter or unwanted echoes.

[0004] Similarly, optical detection and ranging (LiDAR) uses light pulses or continuous waves to measure the relative position and velocity of one or more objects in the environment. The narrow beam width in LiDAR measurements reduces clutter or transient signal amounts in the measurement. However, using higher carrier frequencies in LiDAR measurements typically increases the Doppler effect and results in a mixture of signals associated with relative position and velocity. Summary of the Invention

[0005] An embodiment of an integrated circuit is described. The integrated circuit includes multiple stages. At a given time, the integrated circuit is configured to use one or more of the stages when processing a received signal associated with a measurement in the environment. For example, control circuitry or control logic in the integrated circuit configures the use of one or more of the stages in the integrated circuit. A first stage performs coherent interference suppression by correcting the received signal for a predicted complex signal (such as amplitude and phase) associated with a spurious source. Furthermore, a second stage performs equalization of the received signal, at least in part, based on a target criterion. Additionally, a third stage combines different received signals (such as received signals associated with different measurements) and detects one or more peaks in the received signal.

[0006] For example, the predicted complex signal can include predicted values ​​and predicted phases associated with spurious sources within multiple frames of the measurement.

[0007] In addition, measurements may include lidar measurements and / or radar measurements.

[0008] Furthermore, the received signal can be corrected in the frequency domain for the predicted complex signal.

[0009] Furthermore, stray signals can be associated with reflections from windows or enclosures. Therefore, stray signals can be located at short distances from integrated circuits or measurement devices associated with integrated circuits (such as lidar measurement devices).

[0010] In some embodiments, equalization can be performed in the frequency domain.

[0011] Note that target criteria may include: constant average energy in the frequency domain; constant moments of the distribution of magnitude squares in the frequency domain (such as the median); or an increase in magnitude squares at frequencies greater than a predefined value (such as the frequency corresponding to the maximum range of the integrated circuit).

[0012] Furthermore, the target criteria can be based at least in part on performance metrics associated with peak detection. Alternatively or additionally, the target criteria can ensure that the noise distribution associated with the received signal has a desired (e.g., predefined or predetermined) shape when the received signal corresponds to no return signal during the measurement.

[0013] Furthermore, the received signal can correspond to an optical signal with a carrier frequency that varies over time using a predefined function (such as a sawtooth function, trigonometric function, etc.). Therefore, the received signal can correspond to a chirped optical signal.

[0014] In some embodiments, the order of the stages in the integrated circuit can be rearranged or can be different.

[0015] Note that the integrated circuit may include a transformation circuit that performs a Fourier transform (such as a Fast Fourier Transform or FFT) of the received signal before multiple stages.

[0016] Furthermore, the operations performed by this integrated circuit can be executed in hardware and / or software. It is important to note that the stages within this integrated circuit can operate independently of each other.

[0017] Furthermore, the third level can combine the squares or logarithms of different measurements in the frequency domain. Note that different measurements can use different electromagnetic emission signals: in different channels or frequency bands and / or with different polarizations (e.g., for different measurements, to eliminate speckle).

[0018] Additionally, the third stage can, for example, use a constant false alarm rate (CFAR) estimation technique (such as cell-averaged CFAR) to detect one or more peaks in the received signal. Note that CFAR is one type of detection technique that can be used in this disclosure. Alternatively, or possibly in combination with CFAR, peak detection can be performed using a fixed comparison threshold.

[0019] In some embodiments, the CFAR estimation technique may include determining a threshold corresponding to a noise level in the frequency domain. Furthermore, the third stage may: detect one or more peaks in the received signal based at least in part on the detection probability and the false alarm rate; and / or estimate false alarms in one or more peaks in the received signal. Note that a local maximum detector may be used to detect the one or more peaks, at least in part on the number of one or more peaks, and / or at least in part on a comparison with a threshold.

[0020] In addition, the third level can block the detection of a set of blocked peaks in the received signal.

[0021] Furthermore, for different received signals, at least some of the operations in multiple stages can be repeated.

[0022] In addition, the third stage can reverse the equalization correction performed by the second stage in order to obtain the true energy of the received signal.

[0023] Another embodiment provides an electronic device including the integrated circuit.

[0024] Another embodiment provides a system including the integrated circuit.

[0025] Another embodiment provides a method for selectively performing processing of received signals. The method includes at least some of the operations performed by the integrated circuit.

[0026] This invention is provided for the purpose of illustrating some exemplary embodiments to provide a basic understanding of some aspects of the subject matter described herein. Therefore, it will be understood that the above features are illustrative and should not be construed as narrowing the scope or spirit of the subject matter described herein in any way. Other features, aspects, and advantages of the subject matter described herein will become clear from the following detailed description, drawings, and claims. Attached Figure Description

[0027] Figure 1 This is a block diagram illustrating a processing circuit for receiving signals according to some embodiments of the present disclosure.

[0028] Figure 2 This is a flowchart illustrating an example of a method for selectively performing processing of received signals according to some embodiments of the present disclosure.

[0029] Note that in the accompanying drawings, similar reference numerals always refer to the corresponding parts. Furthermore, multiple instances of the same part are designated by a common prefix separated from the instance number by a dash. Detailed Implementation

[0030] An integrated circuit is described. This integrated circuit may include multiple stages. At a given time, the integrated circuit can be configured to use one or more of the stages when processing received signals associated with measurements in the environment. For example, control circuitry or control logic in the integrated circuit can configure the use of one or more of the stages in the integrated circuit. A first stage in the stages can perform coherent interference suppression by correcting the received signal for a predicted complex signal associated with a spurious source. Furthermore, a second stage in the stages can perform equalization of the received signal, at least in part, based on a target criterion. Additionally, a third stage in the stages can combine different received signals (such as received signals associated with different measurements) and can detect one or more peaks in the received signal.

[0031] By selectively performing processing, these circuit techniques enable integrated circuits to have improved performance. For example, the integrated circuit can be able to detect peaks in a received signal more accurately (e.g., with a reduced false detection rate) and thus determine the relative position and velocity of one or more objects in the surrounding environment. Therefore, these circuit techniques can facilitate the increased use of the integrated circuit in a wide variety of systems, electronic devices, and applications. For example, the integrated circuit can be used in semi-autonomous and / or autonomous or fully autonomous vehicles.

[0032] Embodiments of the circuit techniques will now be described. These circuit techniques can be implemented using one or more integrated circuits. The one or more integrated circuits may include some or all of the described components and their associated functions.

[0033] Figure 1 A block diagram illustrating a processing circuit 100 for receiving signals, such as reflected signals in a measurement system using lidar and / or radar, is presented. During operation, a control circuit 110 in the processing circuit configures the use of one or more stages in the processing circuit 100. The processing circuit 100 may provide an interference suppression engine for the received signal corresponding to or associated with lidar and / or radar measurements. For example, the received signal may include a frequency-modulated continuous wave (FMCW) signal. However, in other embodiments, the received signal may include a pulse signal. In the discussion below, the FMCW signal is used as an illustrative example.

[0034] Lidar and / or radar measurements can utilize chirped signals in which the carrier frequency of the transmitted signal varies over time (and therefore the carrier frequency of the received signal as well). For example, during a chirped frame, the carrier frequency can vary linearly between a start carrier frequency and an end carrier frequency. This predefined chirped pattern can be repeated once or multiple times within a chirped frame. Furthermore, the predefined chirped pattern can be repeated in subsequent chirped frames. In some embodiments, the predefined chirped pattern may include a sawtooth pattern, a triangular wave pattern, or a trapezoidal pattern. The triangular wave pattern allows the contributions in the received signal associated with relative position and velocity to be separated or deblurred. Note that the relative position and velocity in the received signal can be measured by the following steps: causing the received signal to beat with the transmitted (or chirped) signal, thereby obtaining a beat frequency that is proportional to the time delay of the received signal and the slope of the carrier frequency over time; and the Doppler effect caused by the relative velocity difference between the sensor and the target for the wavelength used in the measurement.

[0035] Using the processing circuit 100, the received signal (such as reflected signal) in the lidar measurement and / or radar measurement can be adjusted before peak detection to suppress interference sources (such as FM radio, electromagnetic interference from a circuit board including the integrated circuit with the processing circuit 100, intentional jammers, bumper or housing reflections, etc.) and / or to homogenize background noise. This processing can improve or optimize peak detection, thereby resulting in increased detection probability, reduced false alarm probability, and / or accuracy.

[0036] like Figure 1 As shown, the processing circuit 100 may include several stages that can be used, bypassed, and / or reordered.

[0037] The first stage in processing circuitry 100 may include a traceable interference estimator. This stage or block may be useful for traceable or predictable interference sources. For example, the magnitude and phase of the interference source can be estimated with reasonable accuracy. In some embodiments, the interference source may include: bumper or housing reflections, other parasitic reflections in the optical domain, and / or radio frequency interference (RFI) associated with a synchronization clock, which is in an integrated circuit including processing circuitry 100 and / or in a circuit board including the integrated circuit and one or more interleaved analog-to-digital converter (ADC) spurious signals.

[0038] The trackable interference estimator can receive the complex output of an FFT. Then, based at least in part on monitoring statistics for each FFT bin, the trackable interference estimator can determine which bins to track. In some embodiments, the trackable interference estimator can automatically select the bins to track, or the user can directly indicate the bins to track. For example, the trackable interference estimator can determine which bins to track itself based at least in part on pre-programmed logic or using one or more other techniques, or it can determine the bins based at least in part on user input, such as user input providing bin information to the trackable interference estimator. For each of these bins, the trackable interference estimator can track the complex value and can estimate the complex value for the next FFT (such as the FFT of the received signal associated with the next predefined chirp pattern or the next chirp frame). This estimate can be subtracted from the FFT of the received signal on a bin-by-bin basis. Note that the suppression level may be limited by the estimation quality.

[0039] The second stage in processing circuitry 100 may include an equalization vector estimator. This stage or block may be useful for interference sources whose magnitude and / or phase are untraceable. However, the magnitude may be fairly stable over frequency. Examples include: FM radio stations, interference associated with IEEE 802.11 (sometimes referred to as Wi-Fi), radar, and / or other electromagnetic interference sources that are stable within a given frequency band or multiple frequency bands.

[0040] An equalization vector estimator can receive the magnitude square, magnitude logarithm, or magnitude of an FFT of the received signal. Then, based at least in part on this FFT and monitoring of statistics for each frequency point, the equalization vector estimator can compute an equalization array that flattens the noise distribution (such as cross-frequency points). For example, the average energy across frequency points or individual frequency points can be constant. Alternatively or additionally, when the measuring device outputting the transmitted signal is pointed towards the sky (and therefore, when there is no return or received signal), the noise distribution can be flat (or can have a level or zero slope as a function of frequency or across frequency points). Note that when a "sky measurement" is unavailable, the equalization vector estimator can use statistics from the received signal to compute the equalization vector. In some embodiments, the output of the equalization vector estimator can be an equalization vector that can be multiplied point-by-point (or frequency-by-frequency) with the input received signal. Complex vector multiplication by real vector operations and the calculation of magnitude squares, magnitude logarithms, or magnitudes can be interchanged to balance computational complexity with performance.

[0041] In some embodiments, the equalization performed by the equalization vector estimator is at least partially based on a target criterion. For example, the target criterion may include: a constant average energy in the frequency domain (such as across frequency points); a constant moment of the distribution of the square of magnitudes, the logarithm of magnitudes, or the magnitude of amplitudes (such as the median) in the frequency domain (such as across frequency points); or an increase in the square of magnitudes, the logarithm of magnitudes, or the magnitude of amplitudes at frequencies greater than a predefined value (such as frequencies or frequency points corresponding to the maximum range of processing circuitry 100). Furthermore, the target criterion may be at least partially based on a performance metric associated with peak detection in the received signal. Alternatively or additionally, the target criterion may ensure that the noise distribution associated with the received signal has a desired (e.g., predefined or predetermined) shape when there is no return signal during the period corresponding to the received signal (such as a so-called "sky measurement").

[0042] The summation in processing circuit 100 can perform incoherent integration from multiple acquisitions (such as...) Figure 1 (As indicated by block 112 in "A"). This can be across a despeckle channel, from different modes, from different times, different polarizations, etc. Therefore, the summation can combine received signals associated with different measurements. For example, different measurements can use electromagnetic transmission signals in different channels or frequency bands and / or electromagnetic transmission signals with different polarizations (e.g., thus despeckle for different measurements). In some embodiments, the summation can combine the squares, values, or logarithms of the magnitudes of different measurements.

[0043] The CFAR noise estimator in the processing circuit 100 can implement CFAR estimation techniques (such as cell-averaged CFAR or CA-CFAR, ordered statistical CFAR or OS-CFAR, maximum value in CFAR or GOF-CFAR, etc.). CFAR noise estimation can estimate the noise at each FFT frequency point based at least in part on information from the neighbors (or neighboring frequencies) of each FFT frequency point.

[0044] Furthermore, the alpha array estimator in processing circuitry 100 can use CFAR estimation techniques to calculate an estimate of the noise, and then multiply that estimate by a scalar to adjust the false alarm detection probability. The alpha array estimator can calculate an array (rather than a scalar), which can be used to adjust the false alarm and detection probabilities on a frequency-by-frequency basis. Therefore, products with an alpha array can provide a threshold against which the FFT of the received signal is compared to detect one or more peaks (such as a peak at 92.7 MHz). In some embodiments, the amplitude of the received signal may need to be 3 to 15 times the estimated noise level to be considered a candidate for peak detection.

[0045] Note that the input to the alpha array estimator can be: an equalization vector to compensate for the influence of the blanking frequencies in the FFT; and / or information from the false alarm detector, such that the detection threshold of the frequencies that generate a large number of false alarms increases over time.

[0046] Furthermore, the processing circuitry 100 may include a local maximum finder to add additional constraints to the detected peak. For example, to be considered a peak, the amplitude of a frequency point may need to be a local maximum and the amplitude may exceed a CFAR threshold. More commonly, the one or more peaks may be detected by: using a local maximum detector; based at least in part on the number of one or more peaks; and / or based at least in part on a comparison with a CFAR threshold.

[0047] Additionally, the processing circuitry 100 may include a non-lookable peak block. This block can be a mask that can be used to mark one or more FFT frequency points as non-lookable. This can be a suppression strategy for frequency points with statistical characteristics that make other suppression strategies (such as trackable interference, equalization vectors, and alpha arrays) less effective or ineffective. The non-lookable peak estimator can receive input from a false alarm detector and can decide whether to make some FFT frequency points non-lookable. For example, due to the narrow width in lidar measurements, the FFT of the received signal for adjacent chirped frames or corresponding to adjacent chirped frames in a scanning system may correspond to the same or nearby points in space. When a sudden change in relative position and / or velocity is detected (relative to the results of adjacent chirped frames), these measurements can be considered as deviations from the pattern, and when their corresponding FFT frequency points are frequent false alarms, and neither the first nor the second stage can adequately suppress false alarms, the corresponding frequency points in the FFT of the received signal can be blocked.

[0048] Note that when one or more peaks are detected, the processing circuit 100 can reverse the equalization correction performed by the equalization vector estimator (e.g., in magnitude correction) in order to obtain the true energy of the received signal.

[0049] In some embodiments, different estimator blocks can be used for blocking detection, weather detection, deliberate interference detection, etc. This is because these blocks can calculate different statistical measures of the received signal. For example, when the equalization vector estimation finds a much higher standard deviation at low frequencies than at high frequencies, this may indicate poor weather conditions. Furthermore, a standard deviation below a predefined value at all frequencies above bumper reflections may indicate that the transmitted and / or received signals are blocked.

[0050] As previously mentioned, in some examples of this system, peak detection can be performed without using CFAR to obtain a comparison threshold. However, the third level can perform peak detection by establishing a fixed comparison threshold and omitting CFAR (e.g., using LiDAR measurements). The alpha array can use a fixed comparison threshold to establish the threshold detection level. Using a fixed comparison threshold allows the system to perform better and reduces overall computational cost. The performance improvement and reduced computational cost are likely due to the use of equalization vectors and / or the omission of CFAR. This method allows for the determination of the location of noise, and therefore can be used to establish a fixed comparison threshold to achieve a certain false alarm and detection probability.

[0051] Note that the equalization vector, searchable peak, interference estimation, and / or alpha array can be tracked individually for each channel and / or each slope in the chirped frame.

[0052] In some embodiments, radar measurements may include thousands of chirped or chirped frames. However, the Doppler effect may be smaller than in lidar measurements. Lidar measurements can use a carrier frequency of approximately 200 THz. In lidar measurements, the Doppler effect may be much larger than in radar measurements and may be present in a single frame. Furthermore, lidar measurements can be performed in microseconds, rather than milliseconds, as used for radar measurements. Note that the received signal for one frame provides a beat frequency and thus the distance to the object emitting the signal from the reflective radar and / or lidar.

[0053] Because lidar scatters less, measurement points can correspond to millidegrees. Furthermore, lidar measurements exhibit less clutter compared to radar measurements. In fact, lidar measurements can be used to track clutter across multiple frames, allowing integrated circuits to dynamically adjust or adapt to the clutter. In some embodiments, short chirped frames in lidar measurements can allow tracking of real targets or objects in the environment, as well as atmospheric conditions. Note that the processing performed by the processing circuit 100 can be performed on the received signal associated with each chirped or chirped frame.

[0054] Note that, Figure 1 The values ​​listed are illustrative examples. Different values ​​may be used in other embodiments. Furthermore, Figure 1 The processing circuitry may include fewer or additional components, two or more components may be combined into a single component, a single component may be implemented using two or more separate components, and / or the positions of one or more components may be changed.

[0055] Now, embodiments of the method will be described. Figure 2 The diagram illustrates the use of, for example, integrated circuit 100 ( Figure 1This is a flowchart illustrating an example of a method 200 in which an integrated circuit, such as an ASIC, selectively performs processing of a received signal. During operation, control circuitry within the integrated circuit can configure the integrated circuit (operation 210) to use one or more stages within the integrated circuit. The integrated circuit can then use these one or more stages to process the received signal (operation 212).

[0056] In some embodiments of method 200, additional or fewer operations may be present. Furthermore, the order of operations may be changed, and / or two or more operations may be combined into a single operation.

[0057] The disclosed integrated circuits and circuit technologies can be any electronic device or system (or can be included in any electronic device or system). For example, electronic devices can include: cellular phones or smartphones, tablet computers, laptop computers, notebook computers, personal or desktop computers, netbook computers, media player devices, e-book devices, MiFi® devices, smartwatches, wearable computing devices, portable computing devices, consumer electronics devices, access points, routers, switches, communication equipment, test equipment, vehicles, ships, aircraft, automobiles, trucks, buses, motorcycles, manufacturing equipment, farm equipment, construction equipment, or another type of electronic device.

[0058] While specific components are used to describe embodiments of an integrated circuit, in alternative embodiments, different components and / or subsystems may be present in the integrated circuit. Therefore, embodiments of an integrated circuit may include fewer components, additional components, different components, two or more components may be combined into a single component, a single component may be separated into two or more components, one or more locations of one or more components may be changed, and / or different types of components may exist.

[0059] Furthermore, the circuits and components in the integrated circuit embodiments can be implemented using any combination of analog and / or digital circuit systems including bipolar, PMOS, and / or NMOS gates or transistors. Additionally, the signals in these embodiments can include digital signals with approximately discrete values ​​and / or analog signals with continuous values. Furthermore, these components and circuits can be single-ended or differential, and the power supply can be unipolar or bipolar. Note that the electrical coupling or connection in the foregoing embodiments can be direct or indirect. In the foregoing embodiments, a single line corresponding to a trace can indicate one or more single lines or traces.

[0060] As mentioned above, an integrated circuit can implement some or all of the functions of circuit technology. The integrated circuit may include hardware and / or software mechanisms for implementing the functions associated with the circuit technology.

[0061] In some embodiments, the output of a process for designing an integrated circuit or a portion thereof that includes one or more of the circuits described herein may be a computer-readable medium such as magnetic tape, optical disc, or magnetic disk. The computer-readable medium may be encoded with data structures or other information describing a circuit system that can be physically instantiated as an integrated circuit or a portion thereof. Although various formats may be used for such encoding, these data structures are generally written in the following formats: Caltech Intermediate Format (CIF), Calma GDS II Stream Format (GDSII), Electronic Design Exchange Format (EDIF), Open Access (OA), or Open Artwork System Interchange Standard (OASIS). Those skilled in the art of integrated circuit design can develop such data structures based on schematic diagrams and corresponding descriptions of the types detailed above, and encode the data structures on a computer-readable medium. Those skilled in the art of integrated circuit manufacturing can use such encoded data to manufacture integrated circuits that include one or more of the circuits described herein.

[0062] While some operations in the foregoing embodiments are implemented in hardware or software, these operations can typically be implemented in a wide variety of configurations and architectures. Therefore, some or all of the operations in the foregoing embodiments can be performed in hardware, software, or both. For example, at least some operations in circuit technology can be implemented using program instructions executed by a processor or in firmware within an integrated circuit.

[0063] Furthermore, while examples of numerical values ​​have been provided in the foregoing discussion, different numerical values ​​are used in other embodiments. Therefore, the numerical values ​​provided are not intended to be limiting.

[0064] In the foregoing description, "some embodiments" refers to a subset of all possible embodiments, but does not always specify the same subset of embodiments.

[0065] The foregoing description is intended to enable any person skilled in the art to make and use this disclosure, and is provided in the context of a particular application and its requirements. Furthermore, the foregoing description of embodiments of this disclosure has been shown for purposes of illustration and description only. They are not intended to be exhaustive or to limit this disclosure to the forms disclosed. Therefore, many modifications and variations will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments and applications without departing from the spirit and scope of this disclosure. Additionally, the discussion of the foregoing embodiments is not intended to limit this disclosure. Therefore, this disclosure is not intended to be limited to the embodiments shown, but is to be given the broadest scope consistent with the principles and features disclosed herein.

Claims

1. An integrated circuit, comprising: Multiple levels; and A control circuit configured to configure the use of one or more of the stages, wherein, at a given time, the integrated circuit is configured to use one or more of the stages when processing received signals associated with measurements in the environment, and wherein: The first stage of the stage is configured to perform coherent interference suppression by correcting the received signal for a predicted complex signal associated with a spurious source; The second stage in the series is configured to perform equalization of the received signal at least in part based on a target criterion; and The third stage in the series is configured to combine different received signals and detect one or more peaks in the received signals.

2. The integrated circuit according to claim 1, wherein, The different received signals correspond to different measurements in the measurement.

3. The integrated circuit according to claim 1, wherein, The predicted complex signal includes predicted values ​​and predicted phases associated with the spurious source within multiple frames of the measurement.

4. The integrated circuit according to claim 1, wherein, The measurements include: lidar measurements, radar measurements, or both.

5. The integrated circuit according to claim 1, wherein, The received signal is corrected in the frequency domain for the predicted complex signal.

6. The integrated circuit according to claim 1, wherein, The stray signals are associated with reflections from windows or the enclosure.

7. The integrated circuit according to claim 1, wherein, The equalization is performed in the frequency domain.

8. The integrated circuit according to claim 1, wherein, The target criteria include: constant average energy in the frequency domain; constant moments of the distribution of the square magnitude of the magnitude in the frequency domain; or an increase in the square magnitude of the magnitude at frequencies greater than a predefined value.

9. The integrated circuit according to claim 1, wherein, The target criteria are based, at least in part, on performance metrics associated with peak detection.

10. The integrated circuit according to claim 1, wherein, The target criterion is that the noise distribution associated with the received signal has a predefined or predetermined shape when the received signal corresponds to no return signal during the measurement.

11. The integrated circuit according to claim 1, wherein, The received signal corresponds to an optical signal with a carrier frequency that varies over time using a predefined function.

12. The integrated circuit according to claim 1, wherein, The order of the stages in the integrated circuit is configurable.

13. The integrated circuit according to claim 1, wherein, The integrated circuit includes a transformation circuit configured to perform a Fourier transform on the received signal before the plurality of stages.

14. The integrated circuit according to claim 1, wherein, The integrated circuit is configured to perform operations performed by the integrated circuit in hardware, software, or both.

15. The integrated circuit according to claim 1, wherein, The stages in the integrated circuit are configured to operate independently of each other.

16. The integrated circuit according to claim 1, wherein, The third level is configured to combine the squares of the different measurements in the frequency domain; and The different measurements used are: electromagnetic emission signals in different channels or frequency bands, or electromagnetic emission signals with different polarizations, or both.

17. The integrated circuit according to claim 1, wherein, The third stage is configured to use a constant false alarm rate (CFAR) estimation technique to detect one or more peaks in the received signal; and The CFAR estimation technique includes one or more of the following: determining a threshold corresponding to the noise level in the frequency domain; detecting the one or more peaks in the received signal based at least in part on the detection probability and the false alarm rate; or estimating the false alarms of the one or more peaks in the received signal.

18. The integrated circuit according to claim 1, wherein, The third stage is configured to detect one or more peaks in the received signal based on a fixed comparison threshold.

19. The integrated circuit according to claim 1, wherein, The one or more peaks are detected by: using a local maximum detector; based at least in part on the number of the one or more peaks; or based at least in part on a comparison with a threshold determined using a constant false alarm rate (CFAR) estimation technique.

20. The integrated circuit according to claim 1, wherein, The third level is configured to block the detection of a set of blocked peaks in the received signal.

21. The integrated circuit according to claim 1, wherein, For the different received signals, at least some of the operations in the plurality of stages can be repeated; and The different received signals correspond to different electromagnetic transmission signals: electromagnetic transmission signals in different channels or frequency bands, or electromagnetic transmission signals with different polarizations, or both.

22. The integrated circuit according to claim 1, wherein, The third stage is configured to reverse the equalization correction performed by the second stage.

23. A method for selectively performing processing of a received signal, comprising: From integrated circuits: Configure the use of one or more of a plurality of stages in the integrated circuit, wherein, at a given time, the integrated circuit uses one or more of the stages when processing the received signal associated with a measurement in the environment; and Processing the received signal, wherein, during the processing: The first stage in the series performs coherent interference suppression by correcting the received signal for a predicted complex signal associated with a spurious source; The second stage in the series performs equalization of the received signal at least in part based on the target criterion; and The third stage in the series combines different received signals and detects one or more peaks in the received signals.

24. A system comprising: Integrated circuit, wherein the integrated circuit includes: Multiple levels; and A control circuit configured to configure the use of one or more of the stages, wherein, at a given time, the integrated circuit is configured to use one or more of the stages when processing received signals associated with measurements in the environment, and wherein: The first stage of the stage is configured to perform coherent interference suppression by correcting the received signal for a predicted complex signal associated with a spurious source; The second stage in the series is configured to perform equalization of the received signal at least in part based on a target criterion; and The third stage in the series is configured to combine different received signals and detect one or more peaks in the received signals.

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