Transmitter and radar chip

Abstract

The invention discloses a transmitter and a radar. The transmitter comprises a signal transmitting link and a compensation unit. Wherein the signal transmitting link comprises a first signal generator used for generating a baseband signal; the second signal generator is used for generating a local oscillator signal; the radio frequency transmitting circuit is connected with the first signal generator and the second signal generator and is used for outputting a radio frequency signal for radar detection by utilizing the baseband signal and the local oscillator signal; and the compensation unit is used for inputting the generated offset signal to a signal transmitting link so as to offset the harmonic signal in the radio frequency signal.

Description

[0001] This application is an application filed with priority to the invention patent application with application number 202310702586.5, application date June 14, 2023, and invention name "Signal transmission, calibration, compensation and transceiver link, IQ mixer, integrated circuit, sensor and equipment". Technical Field

[0002] This article relates to radar technology, particularly a transmitter and a radar chip. Background Art

[0003] Radar is a circuit that uses self-transmitted and self-received signals to detect the environment. With the application of radar in more application scenarios, higher requirements are put forward for the coverage rate and signal-to-noise ratio of the radar's scanning area. Therefore, in actual engineering, it is necessary to improve the characteristics of the RF circuit in the radar to meet the needs of radar downstream products. Summary of the invention

[0004] Embodiments of the present application provide a transmitter and a radar chip.

[0005] A transmitter comprises a signal transmission link and a compensation unit; wherein:

[0006] The signal transmission link comprises:

[0007] A first signal generator, used to generate a baseband signal;

[0008] A second signal generator, used for generating a local oscillator signal;

[0009] A radio frequency transmitting circuit, connected to the first signal generator and the second signal generator, and configured to output a radio frequency signal for radar detection using the baseband signal and the local oscillator signal;

[0010] The compensation unit is used to generate a cancellation signal and output it to a signal transmission link to cancel the harmonic signal in the radio frequency signal.

[0011] Exemplarily, the phase of the baseband signal is adjustable.

[0012] Exemplarily, the first signal generator includes:

[0013] A digital baseband signal source for generating a baseband signal sequence with controlled phase shift in a digital domain;

[0014] The digital-to-analog converter is connected to the digital baseband signal source, converts the baseband signal sequence into an analog baseband signal and outputs the analog baseband signal.

[0015] Exemplarily, the compensation unit includes:

[0016] An acquisition circuit, coupled to the radio frequency transmitting circuit, for acquiring a signal in the radio frequency transmitting circuit to obtain a sampling signal;

[0017] The cancellation signal generator is used to generate the cancellation signal according to the harmonic information carried in the sampling signal.

[0018] Exemplarily, the transmitter further includes an adder, coupled to the compensation unit and the first signal generator, for combining the cancellation signal and the baseband signal.

[0019] Exemplarily, the compensation unit includes at least one of the following:

[0020] A third harmonic generator, used for generating a third harmonic signal in the cancellation signal;

[0021] The fifth harmonic generator is used to generate the fifth harmonic signal in the cancellation signal.

[0022] Exemplarily, the compensation unit and the first signal generator are independent of each other.

[0023] Exemplarily, the radio frequency transmission circuit includes a mixer;

[0024] The input end of the acquisition circuit is connected to the output end or the signal detection end of the mixer; or,

[0025] The input end of the acquisition circuit is connected to the RF output end or the RF detection end of the RF transmitting circuit.

[0026] Exemplarily, the acquisition circuit includes: a power detection circuit, or a down-mixer.

[0027] An embodiment of the present application provides a radar chip, comprising the transmitter described above.

[0028] Exemplarily, the compensation unit obtains a sampling signal through a BIST module in the radar chip; the compensation unit detects harmonic information in the signal provided by the BIST module and generates a cancellation signal.

[0029] The embodiment of the present application performs a collection operation on the signal in the signal transmission link to obtain a sampling signal, and uses the sampling signal to generate a cancellation signal, and outputs it to the signal transmission link, so as to use the cancellation signal to suppress the harmonic signal in the radio frequency signal and reduce the harmonic component in the radio frequency signal, thereby improving the signal quality of the radio frequency signal output by the transmitter, and further improving the receiving performance of the receiver for the radio frequency signal.

[0030] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by implementing the present application. Other advantages of the present application can be realized and obtained by the schemes described in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are used to provide an understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0032] Figure 1A A simplified schematic diagram of the signal transmission link for simulating a phase shifter architecture;

[0033] Figure 1B for Figure 1A A simplified schematic diagram of an analog phase shifter in a signal transmission link is shown;

[0034] Figure 2A A schematic diagram of the structure of a signal transmission link provided in an embodiment of the present application;

[0035] Figure 2B for Figure 2A Another structural schematic diagram of the signal transmission link shown;

[0036] Figure 2C A simplified schematic diagram of a signal transmission link of a digital phase shifter architecture in an embodiment of the present application;

[0037] Figure 2D This is a schematic diagram of the structure of the first mixer 221 in the embodiment of the present application;

[0038] Figure 3 A schematic diagram of the structure of a transmitter provided in an embodiment of the present application;

[0039] Figure 4 A schematic diagram of a digital phase shifter architecture in a signal transmission link according to an embodiment of the present application;

[0040] Figure 5 A schematic diagram of a transmission link including a specific compensation module in an embodiment of the present application;

[0041] Figure 6 It is a schematic diagram of a transceiver link including TX IQ Mod, BIST IQ Mod and RX Real Mixer in an embodiment of the present application;

[0042] Fig. 7A A schematic diagram of a transceiver link including TX IQ Mod, RX IQ De-Mod and LO Freq Diff in an embodiment of the present application;

[0043] Figure 7B Another schematic diagram of a transceiver link including TX IQ Mod, RX IQ De-Mod and LO Freq Diff in an embodiment of the present application;

[0044] Figure 8 A schematic diagram of a transceiver link based on the structure shown in FIG7 in combination with BIST in an embodiment of the present application;

[0045] Fig. 9 It is a schematic diagram of a transceiver link including TX IQ Mod, BIST IQ Mod and RX IQ De-Mod in an embodiment of the present application;

[0046] Fig.10 A schematic diagram of a transceiver link including an auxiliary circuit and a BIST IQ Mod in an embodiment of the present application;

[0047] Fig.11 It is a schematic diagram of another transceiver link including an auxiliary circuit and a BIST IQ Mod in an embodiment of the present application;

[0048] Fig.12 A schematic diagram of a digital pre-compensation HD3 architecture based on a cubic module in an embodiment of the present application;

[0049] Fig.13 A schematic diagram of a digital pre-compensation HD3 architecture based on a frequency doubling waveform generator module in an embodiment of the present application;

[0050] Fig.14 A schematic diagram of calibration compensation of a transmission link based on a digital phase shifter architecture in an embodiment of the present application;

[0051] Fig.15 for Figure 3 A schematic diagram of the structure of a compensation unit in the transmitter shown;

[0052] Fig.16 A connection diagram of a cancellation signal generator provided in an embodiment of the present application;

[0053] Fig.17 for Fig.16 Another structural schematic diagram of the transmitter shown;

[0054] Fig.18 for Fig.17 Another structural schematic diagram of the transmitter shown;

[0055] Fig.19 for Fig.16 A first connection diagram of an acquisition circuit in the transmitter shown;

[0056] Fig. 20for Fig.16 A second connection diagram of the acquisition circuit in the transmitter shown;

[0057] Fig.21 for Fig.16 A third connection diagram of the acquisition circuit in the transmitter shown;

[0058] Fig. 22 A schematic flow chart of a signal cancellation method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0059] The present application describes multiple embodiments, but the description is exemplary rather than restrictive, and it is obvious to those skilled in the art that there may be more embodiments and implementations within the scope of the embodiments described in the present application. Although many possible feature combinations are shown in the drawings and discussed in the specific embodiments, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with any other feature or element in any other embodiment, or may replace any other feature or element in any other embodiment.

[0060] The present application includes and contemplates combinations of features and elements known to those of ordinary skill in the art. The embodiments, features and elements disclosed in the present application may also be combined with any conventional features or elements to form a unique invention scheme. Any features or elements of any embodiment may also be combined with features or elements from other invention schemes to form another unique invention scheme. Therefore, it should be understood that any feature shown and / or discussed in the present application may be implemented individually or in any appropriate combination. Therefore, except for the limitations made according to the attached claims and their equivalents, the embodiments are not subject to other restrictions. In addition, various modifications and changes may be made within the scope of protection of the attached claims.

[0061] In addition, when describing representative embodiments, the specification may have presented the method and / or process as a specific sequence of steps. However, to the extent that the method or process does not rely on the specific order of the steps described herein, the method or process should not be limited to the steps of the specific order described. As will be understood by those of ordinary skill in the art, other sequences of steps are also possible. Therefore, the specific sequence of the steps set forth in the specification should not be interpreted as a limitation to the claims. In addition, the claims for the method and / or process should not be limited to the steps of performing them in the order written, and those skilled in the art can easily understand that these sequences can be changed and still remain within the spirit and scope of the embodiments of the present application.

[0062] Figure 1AThis is a simplified schematic diagram of the signal transmission link that simulates the phase shifter architecture. Figure 1B for Figure 1A A simplified schematic diagram of an analog phase shifter in the signal transmission chain is shown.

[0063] like Figure 1A As shown, when the sensor transmits a signal, for a transmission link, a signal generator 11 such as a phase-locked loop (PLL) generates an LO signal (such as a swept frequency signal in the 77 GHz band), which may be an FMCW signal; an analog phase shifter (Analog PS) 12 performs a phase shift operation on the received LO signal, and then radiates the received LO signal to a predetermined spatial region through a transmitting antenna 13 to perform operations such as target detection and measurement. Optionally, Figure 1A In the transmission link structure shown, the corresponding analog phase shifter architecture can be shown in FIG. 2 , and its specific phase shift principle can be shown in the following formula:

[0064]

[0065] in

[0066] That is, by receiving the LO signal (ie, LO IN ) are phase shifted by 0° and 90° respectively to obtain two signals (i.e., LO I and LO Q ), and after being amplified by a power amplifier (PA), it is fitted into an output signal LO OUT , that is, the output signal LO OUT Compared with LO IN The input signal is phase-shifted by θ, where the value of the phase shift θ is determined by the two signals LO I The amplitude of A and LO Q is determined by the amplitude B.

[0067] In addition, the above analog phase shifter architecture can also be implemented by means of a delay line unit, that is, by using the narrow-band assumption of the signal to perform phase shifting by means of time delay. The principle is shown in the following formula:

[0068]

[0069] Where τ is the delay time of the delay line.

[0070] Since the above-mentioned analog phase shifters have low phase modulation precision (Resolution) and phase modulation accuracy (Accuracy), they cannot meet the current sensor requirements. At the same time, although the phase modulation precision and phase modulation accuracy can be improved through calibration, the analog architecture phase shifter needs to be calibrated off-line, which will greatly increase the difficulty and complexity of engineering implementation and product mass production. At the same time, analog phase shifters also have serious problems such as large area, high loss, stability and channel coupling.

[0071] In view of the above technical problems, the embodiments of the present application provide the following solutions, including:

[0072] Figure 2A This is a schematic diagram of the structure of the signal transmission link provided in the embodiment of the present application. Figure 2A As shown, the signal transmission link is deployed in a transmitter, which has a function of transmitting radio frequency signals. Alternatively, the signal transmission link can also be deployed in a transceiver that has a function of transmitting and receiving radio frequency signals.

[0073] exist Figure 2A In the transmitter shown, the signal transmission link includes: a first signal generator, a second signal generator, and a radio frequency transmission circuit. The first signal generator and the second signal generator generate different signals respectively, and the signals are mixed by the radio frequency transmission circuit to form a radio frequency signal for radar chip detection.

[0074] The first signal generator is used to generate a baseband signal. The baseband signal can be characterized by phase, frequency and / or amplitude, etc., and is not limited to digital signals or analog signals. For example, the first signal generator is a signal source of a digital baseband signal, and the digital baseband signal generated by the first signal generator is a digital baseband signal.

[0075] For example, Figure 2B As shown, the first signal generator includes: a digital baseband signal source and a digital-to-analog converter. The digital baseband signal source is used to generate a baseband signal sequence with controlled phase shift in the digital domain. The digital-to-analog converter is connected to the digital baseband signal source to convert the baseband signal sequence into an analog baseband signal and output it. The digital baseband signal source can be controlled by a bit to change the phase of the baseband signal sequence, so that the electromagnetic waves radiated by the radar chip have better anti-interference performance and can flexibly adjust the radiation angle.

[0076] For example, Figure 2CAs shown, the first signal generator includes a DDFS and a DAC, wherein the DDFS is a phase-adjustable digital baseband signal source that generates a digital baseband signal, and the digital baseband signal is converted by the DAC to obtain an analog baseband signal. Alternatively, the first signal generator is a signal source of an analog baseband signal, which directly generates an analog baseband signal.

[0077] It should be understood that Figure 2C Examples and other adjustable signal generators, the first signal generator can adjust at least one of the phase, frequency and amplitude of the baseband signal to adapt to the detection needs of the radar chip. For example, adjusting the phase of the baseband signal can help the phase of the RF signal output by the RF transmitting circuit to be different from other RF signals in the air. This improves the anti-interference ability of the radar signal (i.e., the RF signal).

[0078] Take the example that the first signal generator can realize phase adjustment of the baseband signal. For example, the first signal generator uses its built-in phase shifter to realize phase adjustment. Figure 2C As shown, a digital phase shifter (DDFS) is used. Not only is the processing complexity of the baseband signal phase adjustment significantly lower than that of the RF signal phase adjustment, but the accuracy of adjusting the baseband signal phase is also higher than that of adjusting the RF signal phase.

[0079] The second signal generator is used to generate a local oscillator signal. The local oscillator signal is a radio frequency signal, for example a frequency modulated continuous wave signal (FMCW signal). The local oscillator signal can be characterized by phase, frequency and / or amplitude, and is not limited to a digital signal or an analog signal.

[0080] Take the second signal generator as an analog circuit as an example. Figure 2C The analog signal source 21 shown in FIG. 2 is, for example, a structure including a phase-locked loop (PLL).

[0081] The radio frequency transmitting circuit is connected to the first signal generator and the second signal generator, and is used to output a radio frequency signal for radar detection using the baseband signal and the local oscillator signal. The radio frequency transmitting circuit synthesizes the baseband signal and the local oscillator signal into the radio frequency signal using mixing, amplification and other circuit technologies. The radio frequency circuit can be a digital circuit or an analog circuit according to the digital signal characteristics or analog signal characteristics of the baseband signal and the local oscillator signal. Figure 3 As shown, the RF transmitting circuit is an analog circuit, which at least includes a mixer 221 .

[0082] exist Figure 2BIn the example shown, the first signal generator in the signal transmission link includes a digital circuit and an analog circuit; wherein the first signal generator uses a digital circuit to realize the baseband signal generation function; the second signal generator and the RF transmission circuit are both analog circuits. Digital-to-analog conversion is performed through a digital-to-analog converter to obtain an analog signal corresponding to the baseband signal, so that the RF transmission circuit can normally process the baseband signal output by the first signal generator. The deployment method of the circuit in the above manner can simplify the occupation of the circuit space by the signal transmission link and optimize the layout of the circuit structure.

[0083] exist Figure 2C In the example shown, a simplified schematic diagram of a signal transmission link of a digital phase shifter architecture in an embodiment of the present application is provided. The signal transmission link can be applied to an electromagnetic wave sensor, and the transmission link may include an analog signal source and a digital phase shifter, wherein the analog signal source may be configured to provide an initial analog signal (such as an LO signal, also called a local oscillator signal), and the digital phase shifter may be configured to provide a phase-shifted signal generated in a digital domain, and the digital phase shifter may also perform a phase shift on the initial analog signal based on the generated phase-shifted signal to perform a preset phase shift operation on the initial analog signal.

[0084] The signal transmission link of the digital phase shifter architecture proposed in this application can effectively improve the phase modulation precision and accuracy of the radar chip, and at the same time avoid nonlinear calibration operations on RF band circuits, such as phase shifters, thereby reducing the complexity and difficulty of engineering implementation. In addition, it can also effectively reduce the transmission link area and loss of the phase shift architecture, improve the stability of the system, and reduce the channel coupling.

[0085] In some optional embodiments, a signal transmission link of a digital phase shifter architecture, Figure 2C It can also be described as a circuit structure including an analog signal source 21, a digital phase shifter (Digital PS) 22 and a transmitting antenna 23. The analog signal source 21 can be configured to provide an LO signal, and the digital phase shifter 22 can be configured to perform a preset phase shift operation on the received LO signal, so that the phase-shifted LO signal is radiated to a preset spatial area through the transmitting antenna 23. The analog signal source 21 can also be a structure including a phase-locked loop PLL, which can provide electromagnetic wave (such as laser, microwave, etc.) signals. The analog signal source 21, the digital phase shifter 22 and the transmitting antenna 23 can be integrated into an integrated device, or can be separate components; for example, the analog signal source 21 and the digital phase shifter 22 can be integrated into a package to form a SoC chip, and the transmitting antenna 23 can be connected through the peripheral port of the chip and formed on a carrier such as a PCB board. At the same time, in some optional embodiments, the transmitting antenna 23 can also be integrated on the chip package to form AiP or AoP, with a chip structure of a packaged antenna.

[0086] like Figure 2C As shown, the digital phase shifter 22 in the embodiment of the present application may include a first mixer (Mixer) 221, a digital-to-analog converter (i.e., DAC) 222 and a phase shift signal source (such as a digital baseband signal source Baseband) 223, etc., that is, the phase shift signal source 223 may be configured to provide a digital phase shift signal; the digital-to-analog converter 222 may be configured to perform analog-to-digital conversion on the received digital phase shift signal to convert the digital phase shift signal into an analog phase shift signal; the mixer 221 may be configured to perform a mixing operation on the received analog phase shift signal with the received electromagnetic wave signal from the analog signal source 21, so as to achieve a phase shift operation of setting the above-mentioned electromagnetic wave signal using the digital phase shift signal. Optionally, when the above-mentioned signal transmission link provides a swept frequency signal, such as providing an FMCW laser signal or an FMCW microwave signal, a swept frequency electromagnetic wave signal can be provided based on the analog signal source 21, and / or a swept frequency digital phase shift signal can be provided based on the phase shift signal source 223, so that after mixing by the mixer 221, a swept frequency continuous wave signal is output.

[0087] In some optional embodiments, based on Figure 2C In the structure shown, the analog signal source 21 can be configured to provide FMCW signals in the centimeter wave band or millimeter wave band (such as 3.1 GHz, 24 GHz, 60 GHz, 77 GHz, etc.) of microwaves, and the phase-shifted signal source 223 can be configured to provide a digital phase-shifted signal at the MHz level (for example, 3 MHz to 5 MHz, such as 3 MHz, 4 MHz, 5 MHz, etc.), that is, the digital-to-analog converter 222 performs digital-to-analog conversion on the digital phase-shifted signal at the MHz level to obtain an analog phase-shifted signal in the corresponding frequency range, and the mixer 221 can be configured to perform up-mixing or down-mixing operations on the received millimeter wave band FMCW signal based on the received analog phase-shifted signal of the fixed frequency band, so as to realize the operation of preset phase shifting of the FMCW signal.

[0088] In some optional embodiments, the centimeter wave signal in the 3.1 GHz frequency band may include 3.1 GHz to 10.6 GHz, such as 3.1 GHz, 5 GHz, 6 GHz, 8 GHz, 10.6 GHz, etc.; the millimeter wave signal in the 77 GHz frequency band may include 76 GHz to 81 GHz signals, such as 76 GHz to 77 GHz, 77 GHz to 79 GHz, 79 GHz to 81 GHz and other swept frequency signals, or 76 GHz, 77 GHz, 78 GHz, 79 GHz, 80 GHz, 81 GHz and other fixed frequency band signals.

[0089] based on Figure 2CIn the structure shown, since the phase-shift signal source 223 provides a digital signal, in order to further adapt the signal characteristics, the first mixer 221 can be set as an IQ Mixer, and the digital-to-analog converter 222 is an IQ DAC. At the same time, the phase-shift signal source 223 can be configured to provide a digital baseband signal source (DDFS) for phase shifting and / or provide a corresponding source signal as a waveform controller (WaveformControl).

[0090] For example, Figure 2C As shown, the signal transmission link (TX digital phase shifter architecture) of the digital phase shifter architecture may include a digital baseband signal source (Baseband), a direct digital frequency synthesizer (Direct Digital Frequency Synthesizer, DDFS for short), an IQ digital to analog converter (Digital to Analog Convertor, DAC for short), a low-pass filter (Low-Pass Filter, LPF for short), an IQ modulator (IQ modulator / IQ Mixer), a power amplifier (Power Amplifier, PA), etc., that is, the baseband signal source is configured to provide a digital phase shift source signal, and the direct digital frequency synthesizer may be configured to implement CDM (Code-Division Multiplexing), DDM (Doppler Division Multiplexing), TDM (Time-Division Multiplexing), SDM (Space Division Multiplexing), CSD (Circuit Switch Data), Digital IF (Digital Intermediate Multiplexing) based on the received source signal. Frequency, digital intermediate frequency) and other signal waveforms and wave transmission methods to achieve flexible configuration of signal transmission form and transmission waveform. Among them, the signal amplified by the power amplifier can be radiated to a preset space area through a transmitting antenna packaged as an integral unit or externally.

[0091] For the signal transmission link of the digital phase shifter architecture in the embodiment of the present application, since the digital phase shifter architecture is configured to generate a baseband signal sequence in the digital domain, and can generate an analog baseband signal through a DAC, and then modulate the transmission signal to a high frequency through an orthogonal mixer, that is, because the baseband signal of the architecture is generated in the digital domain, it has better orthogonality and lower sidelobes, so its phase shift phase can be generated very accurately, resulting in higher phase modulation accuracy.

[0092] Based on the signal transmission link described above, the radio frequency transmission circuit includes at least a first mixer and a power amplifier; wherein: the first mixer is used to use the local oscillator signal output by the second signal generator to up-convert the baseband signal output by the first signal generator; the power amplifier is used to amplify the signal output by the mixer to obtain the radio frequency signal.

[0093] In some optional embodiments, for the signal transmission link of the digital phase shifter architecture, when RF LO frequency scanning is used to implement the transmitted signal as an FMCW signal, the signal transmission link may have problems such as TXIQ imbalance (Imbalance), signal leakage (such as TXLO Leakage), harmonic distortion (HD) and so on caused by IQ mismatch (Mismatch).

[0094] To this end, the present application further provides a transmitter, wherein a compensation unit is additionally provided in the transmitter, wherein the compensation unit is also called a compensation module (or a TX compensation unit, etc.), to solve at least one of the above problems.

[0095] In view of the above technical problems, the embodiments of the present application propose the following solutions, including:

[0096] Figure 3 This is a schematic diagram of the structure of the transmitter provided in the embodiment of the present application. Figure 3 As shown, the transmitter includes a compensation unit and the signal transmission link described above. The compensation unit provides operations such as adjusting the baseband signal and / or inserting a cancellation signal into the baseband signal through calibration, detection, or real-time feedback to solve at least one of the above defects.

[0097] For example, Figure 4 FIG. 1 is a schematic diagram of a digital phase shifter architecture in a signal transmission link according to an embodiment of the present application. Figure 4 As shown, a compensation module (TX compensation) may be provided between the TX DDFS and the IQ DAC to perform operations such as calibration and compensation on the signal transmission link of the digital phase shifter architecture, so as to achieve an operation of solving at least one of the above problems.

[0098] Figure 5 Schematic diagram of a transmission link including a specific compensation module in an embodiment of the present application. In some optional embodiments, such as Figure 5As shown, the compensation module (TX compensation) may include at least one of an LO compensation unit (TXLO leakage compensation), an IQ compensation unit (TX IQ Imbalance compensation) and an HD3 compensation unit (TXHD3 compensation), that is, the LO compensation unit may be configured to perform compensation operations for signal leakage, the IQ compensation unit may be configured to perform compensation operations for IQ imbalance, and the HD3 compensation unit may be configured to perform compensation operations for the above-mentioned HD3. The LO compensation unit is configured to be used to perform compensation operations for at least one of an IQ modulator imbalance (TX IQ Modulator imbalance) and an IQ channel imbalance (IQ channel imbalance). In addition, when the compensation module includes at least two of the LO compensation unit, the IQ compensation unit and the HD3 compensation unit, compensation may be performed synchronously (such as in parallel) or sequentially (such as in series) according to actual needs and signal characteristics. Figure 5 As shown, IQ compensation may be performed first, then LO compensation, and finally HD3 compensation.

[0099] In some optional embodiments, the signal transmission link of the digital phase shifter architecture may also include an error correction module (TXDAC Board Error Correction) for DAC and an AWGN (additive white gaussian noise) module for Gaussian white noise, etc., which are not shown in the figure and can be added or deleted according to actual needs. Among them, IQ mentioned in the embodiments of the present application is represented by In-Phase, Q is represented by Quadrature, and RF is represented by Radio Frequency.

[0100] Figure 6 FIG. 7 is a schematic diagram of a transceiver link in an embodiment of the present application, and FIG. 8 is a schematic diagram of a transceiver link including TXIQ Mod, RX IQ De-Mod and LO Freq Diff in an embodiment of the present application, Figure 8 FIG. 7 is a schematic diagram of a transceiver link based on the structure shown in FIG. 7 in combination with BIST in an embodiment of the present application. Fig. 9 It is a schematic diagram of a transceiver link including TX IQ Mod, BIST IQ Mod and RX IQ De-Mod in an embodiment of the present application.

[0101] The following is a description of the transmit and receive links formed by the transmit link structure described in the embodiments of the present application:

[0102] like Figure 6 As shown, a transceiver link may include a transmitting link and a receiving link, etc. The transmitting link (i.e., a transmitter) may include a digital baseband signal source (Baseband), a direct digital frequency synthesizer (TXDDFS), an IQ digital-to-analog converter (IQ DAC), a low-pass filter (LPF), an IQ modulator (IQ Modulator), a power amplifier (PA), etc., which are connected in sequence. At the same time, the signal amplified by the power amplifier is radiated to a preset spatial area through a transmitting antenna. The receiving link may include a low noise amplifier (LNA), a real mixer (Real Mixer), a trans-impedance amplifier (TIA), a low-pass filter (LPF), a high-pass filter (HPF), a real digital-to-analog converter (Real ADC), etc. connected in sequence. That is, the echo signal received by the receiving antenna is processed by the above-mentioned LNA, Real Mixer, TIA, LPF, HPF and Real ADC in sequence and converted into a real digital baseband signal. The subsequent digital signal processing module processes the real digital baseband signal to obtain parameter information of the target such as distance, speed, angle, height and micro-motion characteristics.

[0103] In the above transceiver link, the frequency of the TX-LO signal received by the IQ modulator in the transmitting link and the frequency of the RX-LO signal received by the Real Mixer in the receiving link may be the same. Figure 6 As shown, if the signal output by the Baseband is a sine wave of x MHz, then the TX-LO signal and the RX-LO signal can both be sine waves of z GHz.

[0104] exist Figure 6 In the embodiment shown, the transmitting link adopts a digital phase-shifting architecture, while the receiving link can adopt components of an analog architecture, that is, no IQ components are used, so it can effectively be compatible with sensors of the receiving link of the analog architecture, effectively reducing the development cost of the entire transceiver link system.

[0105] Optionally, in an embodiment of the present application, the receiving link may include a receiving antenna, that is, the receiving antenna may be connected through a peripheral port of the chip and formed on a carrier such as a PCB board. At the same time, in some optional embodiments, the receiving antenna may also be integrated on the chip package to form AiP or AoP, that is, a chip structure with a packaged antenna.

[0106] In some optional embodiments, in order to match the transmission link of the digital phase shifter architecture, relevant adjustments may be made to the receiving link, such as Fig. 7A The transceiver link shown may include Figure 6 The similar transmission link architecture and receiving link in the example (in order to avoid redundancy, the same parts will not be elaborated here), Figure 6 The RealMixer in the receiving link is adjusted to an IQ demodulator (IQ Demodulator), and the Real ADC is adjusted to an IQ ADC. That is, the receiving link may include a low noise amplifier (LNA), an IQ demodulator (IQ Demodulator), a transimpedance amplifier (TIA), a low pass filter (LPF), a high pass filter (HPF), an IQ digital-to-analog converter (IQADC), etc., which are connected in sequence. That is, the echo signal received by the receiving antenna is processed by the above-mentioned LNA, IQ Demodulator, TIA, LPF, HPF and IQ ADC in sequence and converted into an IQ digital baseband signal. The subsequent digital signal processing module processes the IQ digital baseband signal to obtain parameter information of the target such as distance, speed, angle, height and micro-motion characteristics (i.e., micro-Doppler).

[0107] At the same time, based on Fig. 7A When the transceiver link shown in the figure is self-calibrated, it is only necessary to directly connect the signal output port of the transmission link with the signal input port of the receiving link through a transmission line, that is, the transmission link directly sends the transmission signal to the receiving link through the transmission line, so as to realize the self-calibration operation of the receiving and / or transmission link without passing through the transmitting antenna and the receiving antenna. At this time, there is a certain frequency deviation between the TX-LO signal received by the IQ modulator in the transmission link and the RX-LO signal received by the IQ Demodulator in the receiving link. For example, Fig. 7A As shown, if the signal output by the Baseband is a sine wave of x MHz, the TX-LO signal can be a sine wave of z GHz. At this time, the RX-LO signal is converted into a digital signal after being processed by a down-mixer (i.e., an IQ Demodulator in the receiving link), a low-pass filter, and a high-pass filter, so as to perform TX IQ imbalance calibration.

[0108] In some optional embodiments, such as Fig. 7AAs shown, the transmitting link (the Transmitter, TX shown in the figure) can be calibrated by adding a receiving link (the Receiver, RX shown in the figure), and the compensation operation is performed based on the calibrated data through the TXIQ imbalance compensation module in the transmitting link. At the same time, the transmitting link (the Transmitter, TX shown in the figure) can also be calibrated by multiplexing the receiving link (the Receiver, RX shown in the figure) actually used for signal transmission and reception, and the compensation operation is performed based on the calibrated data through the TX IQ imbalance compensation module in the transmitting link and / or the receiving link. Among them, Fig. 7A This is the signal chain for TX IQ imbalance. Since the signal chain for TX harmonic signal problem is similar to the signal chain for TX IQ imbalance, Fig. 7A The TX IQ imbalance compensation unit in is replaced by the TX HD3 compensation unit to solve the TX HD3 problem. For details, see Figure 7B Similar implementations may also be performed in other embodiments, which will not be described in detail in the following for the sake of simplicity.

[0109] In some optional embodiments, based on Fig. 7A Or based on the structure shown in 7B, in order to achieve accurate calibration of the transceiver link, Fig. 7A Or the RX-LO port of the IQ Demodulator of the receiving link shown in 7B is set to an internal self-test module (Built-in Self-Test, referred to as BIST) module, that is, Figure 8 As shown in Fig. 7A On the basis of the transceiver link structure shown in FIG. 7B , an IQ BIST architecture is set at the RX-LO port of the IQ Demodulator of the receiving link to input an LO signal with a preset frequency deviation at the RX-LO port of the IQ Demodulator of the receiving link. For example, an IQ BIST composed of a phase angle converter and an IQ modulator (IQ Modulator) is used to form an IQ BIST, such as a TX-LO signal received through a phase angle converter through an IQ modulator, to form a frequency-deviation signal based on the frequency deviation signal of another input signal BIST-LO of the IQ modulator, and input it to the RX-LO port of the IQ Demodulator. For example, if the TX-LO signal is a zGHz sine wave, and the BIST-LO signal is a y MHz sine wave, the frequency-deviation signal input to the RX-LO port of the IQ Demodulator is (zGHz-yMHz). It should be noted that, between different embodiments, x, y, and z are all schematic values, and the specific values ​​may be the same or different.

[0110] In some optional embodiments, based on Figure 8 The IQ BIST architecture of the transceiver link structure shown in the figure can also calibrate the transmit link of the digital phase shifter architecture by multiplexing the receive link in the transceiver link; wherein, in other embodiments, the calibration operation of the transmit link using the receive link, and the calibration operation of the receive link using the transmit link, can be implemented by multiplexing the corresponding receive link or transmit link in the link that actually performs signal transmission and reception, and can also be implemented by adding a corresponding calibration receive link or calibration transmit link to implement the calibration operation of the corresponding transmit link or receive link in the link that actually performs signal transmission and reception.

[0111] Optionally, the IQBIST may include a phase angle converter and an IQ modulator (IQ Modulator), the phase angle converter is used to realize the calibration of the I path and Q path in the transmission link of the digital architecture respectively, and the other input signal BIST-LO of the IQ modulator may be a y MHz sine wave (sine wave), which is used to simulate the characteristics related to the echo signal formed by the reflection of the transmission signal by the target, wherein Figure 8 Where x, y, and z are all positive numbers, and x≠y≠z, and can generally be between 0 and 1000.

[0112] Optional, in Figure 8 In the transceiver link shown, a TXIQ imbalance compensation module (TX IQ Imbalance Compensation) may also be provided in the transmitting link (e.g., between the TXDDFS and the IQ DAC), and / or a TX IQ imbalance compensation module (TX IQ Imbalance Compensation) may be provided in the receiving link (e.g., after the Real ADC), so that the transmitted and / or received signals may be supplemented based on the calibration parameters (or coefficients) obtained by the above self-calibration operation to solve problems such as IQ imbalance.

[0113] In some optional embodiments, based on Figure 8 The structure shown, such as Fig. 9 As shown, the above-mentioned IQ BIST module can be set between the signal output port of the transmitting link and the signal input port of the receiving link, that is, the transmitting link directly sends the transmitting signal to the receiving link through the IQ BIST module, so as to realize the self-calibration operation of the receiving link and / or the transmitting link without passing through the transmitting antenna and the receiving antenna.

[0114] It should be noted that, in the transmission chain structure shown in FIGS. 7-9 , only the IQ compensation unit (TX IQImbalance compensation) is illustrated. In actual applications, based on actual needs, an LO compensation unit (TXLO leakage compensation) and an HD3 compensation unit (TXHD3compensation) may be added to the transmission chain to form a compensation module (TXcompensation) including the LO compensation unit (TX LO leakage compensation), the IQ compensation unit (TX IQ Imbalancecompensation) and / or the HD3 compensation unit (TX HD3 compensation).

[0115] Fig.10 Schematic diagram of a transceiver link including an auxiliary circuit and a BIST IQ Mod in an embodiment of the present application, Fig.11 Schematic diagram of another transceiver link including an auxiliary circuit and a BIST IQ Mod in an embodiment of the present application.

[0116] like Fig.10 As shown, a transceiver link, combined with Figure 5 and Fig. 9The structure and related description shown in the figure, the transceiver link may include a transmission link, a receiving link and a calibration link. The transmission link may include a TX digital baseband signal source (TX Baseband), a direct digital frequency synthesizer (TX DDFS), a compensation module (Compensation), an IQ digital-to-analog converter (IQDAC), a low-pass filter (LPF), an IQ modulator (IQ Modulator) and a power amplifier (PA) connected in sequence, and the signal amplified by the power amplifier is radiated to a preset spatial area through a transmitting antenna. The receiving link may include a low noise amplifier (LNA), a real mixer (RealMixer), a trans-impedance amplifier (TIA), a high-pass filter (HPF), a variable gain amplifier (VGA), a real digital-to-analog converter (RealADC) and an RX Baseband for TXRF calibration, etc., which are connected in sequence. That is, the echo signal received by the receiving antenna is processed by the above-mentioned LNA, Real Mixer, TIA, HPF, VGA and Real ADC in sequence and converted into a real digital baseband signal. The subsequent digital signal processing module processes the real digital baseband signal to obtain parameter information of the target such as distance, speed, angle, height and micro-motion characteristics.

[0117] For the transmit link, a compensation module (TXcompensation) disposed between TXDDFS and IQDAC may include an LO compensation unit (TX LO leakage compensation), an IQ compensation unit (TX IQImbalance compensation), and an HD3 compensation unit (TX HD3 compensation), so as to implement corresponding compensation operations such as LO leakage, IQ Imbalance, and HD3 in the transmit link of the digital phase shifter architecture.

[0118] In some optional embodiments, a calibration module may be provided between the transmitting link and the receiving link, and the calibration compensation module may be configured to multiplex the receiving link to perform operations such as calibration on the transmitting link of the above-mentioned digital phase shifter architecture. At the same time, the compensation module may be based on the parameters or coefficients obtained by the calibration operation of the calibration module to implement compensation operations on the transmitting signal at the transmitting link end. In other embodiments, a corresponding receiving compensation module may be provided in the receiving link simultaneously or separately, that is, at this time, the receiving compensation module may be based on the parameters or coefficients obtained by the above-mentioned calibration operation to implement compensation for the echo signal at the receiving link end.

[0119] like Fig.10 As shown, the above-mentioned calibration module may include a BIST unit and an auxiliary circuit unit, that is, the output port of the transmitting link is connected to any node between the RealMixer and the Real ADC in the receiving link through the BIST unit and the auxiliary circuit unit. For example, the IQ Modulator in the transmitting link generates a radio frequency signal of (z GHz±x MHz) based on the digital phase-shifted baseband signal of x MHz and the LO signal of zGHz, and then outputs it to the BIST unit through the output port. The BIST unit performs a frequency deviation operation of y MHz on the received radio frequency signal to obtain an analog echo signal of (z GHz±x MHz±y MHz), and then uses the IQ De-Modulator in the auxiliary unit to reduce the frequency to obtain a preset intermediate frequency signal (z GHz±x MHz±y MHz-z GHz=±x MHz±y MHz). The intermediate frequency signal is then input to a preset node in the receiving link to implement the calibration operation in the transmitting link.

[0120] Optionally, the auxiliary circuit unit may be an orthogonal demodulator circuit, and the output end of the auxiliary circuit unit may be connected to any node among the node between the TIA and the HPF, the node between the HPF and the VGA, and the node between the VGA and the Real ADC in the receiving link. In addition, in order to maximize the reuse of the receiving link structure, after the output port of a transmitting link passes through the BIST unit and the auxiliary circuit unit, the I and Q branches may be respectively connected to different transmitting links, that is, Fig.10As shown, two receiving links are multiplexed to calibrate one transmitting link. After the calibration of the transmitting link is completed, the compensation units such as the LO compensation unit (TX LO leakage compensation), the IQ compensation unit (TX IQ Imbalance compensation) and / or the HD3 compensation unit (TX HD3 compensation) in the compensation module (TX compensation) can be used to implement compensation operations corresponding to the LO leakage, IQ Imbalance and HD3 problems in the transmitting link of the digital phase shifter architecture based on the parameters obtained by the calibration.

[0121] In some optional embodiments, the BIST unit may include a phase angle converter and an IQ modulator (IQ Modulator) connected in sequence, and the auxiliary circuit unit may include an LNA, an IQ De-Modulator and a TIA connected in sequence, that is, the phase angle converter receives the RF signal output from the transmission link, and one input end of the IQ Modulator is connected to the output end of the phase angle converter, and the other input end receives the BIST-LO signal of y MHz to generate a preset echo signal. The LNA sends the received echo signal to an input end of the IQ De-Modulator after amplification, and the other input end of the IQ De-Modulator is used to receive the RX-LO signal of z GHz. The two output branches (i.e., the I branch and the Q branch) of the IQ De-Modulator are respectively connected to the corresponding nodes in the corresponding receiving links after the TIA, so as to output the generated preset intermediate frequency signal to the two receiving links, thereby realizing a more efficient multiplexing receiving link design while realizing the calibration operation.

[0122] It should be noted that, for the calibration operation in the embodiment of the present application, if the transmitting link transmits a swept frequency signal, in the actual calibration operation, the TX LO signal can be used as a single tone signal for point-by-point calibration; at the same time, the TXLO signal can also be used as a swept frequency signal for large bandwidth calibration operations, and even the swept frequency bandwidth calibration can be used once to implement the calibration operation for the swept frequency signal of the entire frequency band.

[0123] based on Fig.10 The structure shown in the figure can be realized by cascading at least two BIST units in order to further suppress the preset degree of HD3, LO Leakage, IQ Imbalance, etc. in the transmission link of the digital phase shifter architecture; Fig.11As shown, by two BIST units connected in series, the noise caused by the above defects can be suppressed to a level of -50 dB, thereby effectively reducing the difficulty of development and design of related link analog devices.

[0124] In some optional embodiments, based on the transmission link of the digital phase shifter architecture described in the embodiments of the present application, when calibrating and compensating for IQ Imbalance, the compensation coefficient of IQ Imbalance can be obtained in the time domain (Time-Domain) based on spectrum analysis, and the compensation coefficient of IQ Imbalance can also be obtained in the frequency domain (Frequency-Domain) based on the spectrum peak ratio.

[0125] In some optional embodiments, in order to further improve the accuracy of the IQ Imbalance compensation coefficient, the ideal compensation coefficient may be approached by iterative calibration and compensation, or the ideal compensation coefficient may be obtained by multi-observation calibration and compensation.

[0126] For example, for the iterative calibration and compensation method, it can be determined whether to stop the iterative operation based on the size relationship between the compensation coefficients of the two calibration compensations, or whether the difference between the compensation coefficients of the two calibration compensations meets the preset iterative conditions, and the compensation coefficient obtained when the iterative operation is stopped is used as the final compensation coefficient in the current scene for subsequent operations. For the multi-observation calibration and compensation method, after multiple (for example, three) calibration and compensation operations, the measurement data obtained from each operation can be subjected to FFT (fast Fourier transform) and the corresponding amplitude and phase information can be obtained. The measurement can be subtracted and normalized to obtain relevant data, and an observation matrix can be constructed; the corresponding compensation coefficient can be reversely solved based on the data obtained by inverting the observation matrix.

[0127] In some optional embodiments, based on the similar idea of ​​obtaining the IQ Imbalance compensation coefficient, the compensation coefficient of LO leakage and / or HD3 may be obtained by adopting a method such as iterative calibration and compensation, or a method of multiple observation calibration and compensation.

[0128] In the above examples of transmitters with compensation units, the problem of solving harmonic distortion in the transmitter is mentioned. It is found through research that some harmonic distortion may be caused by components including nonlinear characteristics such as mixers in the transmitter.

[0129] by Figure 2D For example, Figure 2D Schematic diagram of the structure of the first mixer 221 in the embodiment of the present application. Figure 2DAs shown, the first mixer 221 includes a voltage-current converter (V / I Converter), a current switch (Current Switch) and a current-voltage converter (I / V Converter). The voltage-current converter converts the received voltage signal into a current signal; the current switch is connected to the voltage-current converter and the second signal generator, and is used to process the current signal output by the voltage-current converter using the local oscillator signal; the current-voltage converter is connected to the current switch, and is used to convert the current signal output by the current switch into a voltage signal.

[0130] In the above structure, since the voltage-current converter is provided with a transistor amplifier, based on the nonlinear characteristics of the transistor amplifier and the low frequency characteristics of the baseband signal, the current signal output by the voltage-current converter contains a harmonic signal corresponding to the baseband signal. For example, the HD caused by the third-order nonlinearity of the baseband can be referred to as HD3. Similarly, the harmonic caused by the fifth-order nonlinearity is called HD5. When the current switch processes the current signal output by the voltage-current converter, the frequency of the harmonic is converted to the RF band after up-conversion. Since the operation complexity of suppressing the harmonic signal in the RF band is high, the hardware cost is high. If the harmonic signal in the RF band is not removed, it will affect the signal quality of the radar reception and transmission, and thus affect the accuracy of the radar measurement.

[0131] The compensation unit is used to input the generated cancellation signal into the signal transmission link to cancel the harmonic signal in the radio frequency signal. The compensation unit is independent of the first signal generator; or

[0132] To this end, the compensation unit may include a signal cancellation signal generator. The cancellation signal output by the compensation unit can suppress the harmonic signal in the radio frequency signal, reduce the harmonic component in the radio frequency signal, and thus improve the signal quality of the radio frequency signal output by the transmitter.

[0133] In the embodiment of the present application, for the harmonic signal in the signal transmission link, the compensation unit uses feedback or according to the characteristics of the transmission wave to input the generated cancellation signal into the signal transmission link to cancel the harmonic signal in the RF signal output by the signal transmission link. The cancellation signal has the characteristics of opposite phase and similar amplitude to the harmonic signal transmitted in the RF transmission circuit, so as to achieve the purpose of suppressing the harmonic signal.

[0134] In some examples, the compensation unit generates a compensation signal including a cancellation effect according to parameters such as the phase, frequency, or amplitude of the baseband signal generated by the first signal generator, or even the path length combined with the LO signal.

[0135] For example, Figure 4An example of a transmitter in which a compensation unit is connected to a signal transmission link is shown in FIG. Figure 4 In the structure shown, the compensation unit is a TX compensation unit. The TX compensation unit includes a cancellation signal generator (not shown) that can generate a cancellation signal according to the characteristics of the transmission wave. The cancellation signal generator can be, for example, Figure 5 The TX HD3 compensation unit shown in Figure 2.

[0136] Among them, the baseband processor ( Figure 4 The baseband frame (hereinafter referred to as the baseband frame) controls the orthogonal digital baseband signal generated by the TX DDFS. The TX compensation unit generates an orthogonal compensation signal according to the parameters of the orthogonal digital signal, combines the orthogonal compensation signal and the orthogonal digital signal, and sends them to the IQ DAC to be converted into an analog baseband signal. After LPF filtering, it is sent to the first mixer (i.e., Figure 4 The IQ modulator in the RF transmitter is mixed to obtain a radio frequency signal based on the mixing of the TX LO signal and the analog baseband signal. The PA amplifies the mixed signal and outputs it through the transmitting antenna. The compensation signal cancels at least part of the harmonic signal in the RF transmitting circuit, such as the HD3 harmonic signal. Therefore, the clutter in the transmitted RF signal will be greatly reduced. The RF signal can be an FMCW signal.

[0137] In some other examples, the compensation unit generates a compensation signal according to harmonic information obtained through feedback from the radio frequency transmission circuit. Fig.15 , Fig.15 for Figure 3 The schematic diagram of the structure of the compensation unit in the transmitter is shown in FIG. Fig.15 As shown, the compensation unit includes an acquisition circuit and a cancellation signal generator.

[0138] The acquisition circuit is coupled to the RF transmission circuit, and is used to acquire the signal in the RF transmission circuit to obtain a sampling signal. The sampling signal can reflect the waveform information (also known as harmonic parameters) in the harmonic signal, such as the phase of the main frequency signal, the phase of the harmonic signal, the frequency of the harmonic signal, the frequency of the main frequency signal, the power of the harmonic signal, the power of the main frequency signal, etc.

[0139] It should be noted that the harmonic parameters reflected by the sampling signal are related to the information carried by the signal that can be collected by the acquisition circuit. For example, if the acquisition circuit is a power acquisition circuit, the corresponding sampling signal contains the power of the main frequency. For another example, if the acquisition circuit uses at least part of the circuit of the receiver, the sampling signal reflects the phase of the main frequency signal, the phase of the harmonic signal, the frequency of the harmonic signal, the frequency of the main frequency signal, the power of the harmonic signal, the power of the main frequency signal, etc.

[0140] At least one of the above harmonic parameters can be extracted by analog circuits. For example, the power of the main frequency signal is output through a coupler and a power detector. Or the advantage of the digital circuit in the radar chip in frequency domain calculation is used to extract harmonic parameters. For example, by coupling the RF transmitting circuit, a signal identical to the signal transmitted at the coupling point is obtained as a sampling signal. The sampling signal carries the main frequency signal and the harmonic signal. The sampling signal is converted into a digital signal by an ADC and handed over to the digital circuit for calculation in the frequency domain to obtain more harmonic parameters.

[0141] As shown above, in one implementation, Fig.19 , 20 As shown, the input end of the acquisition circuit is connected to the output end or the signal detection end of the mixer. This method can detect the harmonic signal generated by the voltage-current converter and has a simplified acquisition circuit. Fig.12 , 13 In one connection mode of the structure shown, the input end of the acquisition circuit is connected to the detection end between the voltage-current converter and the current switch, and is coupled to the ADC.

[0142] In another way, Fig.21 As shown, the input end of the acquisition circuit is connected to the RF output end or the RF detection end of the RF transmitting circuit. The RF output end is exemplified as the output end of the RF transmitting circuit. The RF detection end is exemplified as the input end or output end of at least one PA in the RF transmitting circuit. This method can acquire more accurate harmonic parameters in the RF transmitting circuit, but has a more complex circuit structure.

[0143] In some chips including a BIST module, the acquisition circuit can obtain the sampled signal through part or all of the circuits in the BIST module. Fig.13 As shown, the input end of the acquisition circuit is coupled to the RF output end, which includes a down converter, a filter, etc. in sequence, and is connected to the IQ ADC to output a digital sampling signal. Among them, the down converter, the filter, etc. can reuse the BIST module or the receiver.

[0144] The collected sampling signal is input to a cancellation signal generator. The cancellation signal generator is at least one circuit in the compensation unit. The cancellation signal generator is connected to the first signal generator, so that the signal received by the radio frequency transmitting circuit includes both the baseband signal and the cancellation signal.

[0145] For example, the cancellation signal generator includes the cancellation signal generator mentioned above and a digital circuit for extracting harmonic information, wherein the digital circuit for extracting harmonic information can be configured independently, or at least partially shared with the digital circuit in the radar chip.

[0146] The digital circuit for extracting harmonic information uses, for example, a digital circuit for processing difference frequency baseband signals in a radar chip to extract harmonic information such as harmonic frequency, main frequency, and main frequency power, and provides the information to a cancellation signal generator. The cancellation signal generator generates a cancellation signal according to the received parameters.

[0147] For another example, the digital circuit for extracting harmonic information extracts the main frequency amplitude in the sampled signal, and calculates the harmonic amplitude based on the difference between the preset main frequency amplitude and the harmonic amplitude. The cancellation signal generator generates a cancellation signal for the harmonic signal based on the calculated harmonic amplitude and other pre-configured harmonic parameters. The pre-configured harmonic parameters can be calculated based on the sweep frequency range, phase, etc. of the main frequency signal to be transmitted by the radar chip.

[0148] The cancellation signal generator in the cancellation signal generator can be configured independently of the first signal generator, or at least partially shared with the first signal generator. Fig.16 As shown, the cancellation signal generated by the cancellation signal generator is input into the first signal generator, so that the baseband signal output by the first signal generator includes the cancellation signal. Fig.17 , the cancellation signal generator may include a third harmonic generator and a fifth harmonic generator.

[0149] Another example: Fig.18 As shown, the compensation unit further includes an adder coupled to the cancellation signal generator and the first signal generator to combine the baseband signal generated by the first signal generator and the cancellation signal generated by the cancellation signal generator. Fig.18 The cancellation signals exemplified in the example include a cancellation signal Signal_HD3 generated by a third harmonic generator to cancel the third harmonic, and a cancellation signal Signal_HD5 generated by a fifth harmonic generator to cancel the fifth harmonic. The cancellation signals Signal_HD3 and Signal_HD5 and the baseband signal generated by the first signal generator are combined by an adder and output to the RF transmission circuit.

[0150] In summary, the transmitter circuit examples provided in the present application that pre-input a cancellation signal into a radio frequency transmitting circuit in a feedback manner can ensure that the radio frequency signal transmitted by the chip contains sufficiently low harmonic signals under different environments.

[0151] In order to effectively suppress harmonic signals according to the actual operating environment of the chip during use, for example, considering the impact of ambient temperature on semiconductor devices, the present application also provides a method for canceling harmonic signals in the above transmitter using a feedback mechanism. Fig. 22 shown.

[0152] Step 10: performing a sampling operation on the signal in the signal transmission link to obtain a sampled signal; wherein the signal transmission link is used to generate a radio frequency signal for radar detection, wherein the radio frequency signal includes a harmonic signal.

[0153] Step 20: Detect the sampling signal, generate a cancellation signal for canceling the harmonic signal, and output the cancellation signal to the signal transmission link.

[0154] The method provided in the embodiment of the present application performs a collection operation on the signal in the signal transmission link to obtain a sampling signal, and uses the sampling signal to generate a cancellation signal, and outputs it to the signal transmission link, so as to use the cancellation signal to suppress the harmonic signal in the radio frequency signal and reduce the harmonic component in the radio frequency signal, thereby improving the signal quality of the radio frequency signal output by the transmitter, and further improving the receiving performance of the receiver for the radio frequency signal.

[0155] Below with reference to Figures 7 to Fig.14 , an example of a transmitter including a compensation unit and its working process:

[0156] For example, Figure 7B An example of using a feedback mechanism to extract harmonic information from a transmitter so that a compensation unit generates a corresponding cancellation signal is shown in FIG. Figure 7B In the structure shown, the compensation unit includes a TX HD3 compensation unit. The TX HD3 compensation unit generates a compensation signal according to the waveform characteristics of the received signal. The feedback mechanism can be executed in the calibration mode of the radar chip to prevent the signal transmission power of the radar chip from being weakened during normal detection.

[0157] The baseband processor in the transmitter (such as Figure 7B The baseband frame in the TX DDFS controls the orthogonal digital baseband signal generated by the TX compensation unit, and then sends it to the IQ DAC to be converted into an analog baseband signal. The analog baseband signal is mixed with an analog cancellation signal for canceling the harmonic signal in the transmission link. The analog baseband signal is filtered by the LPF and then enters the first mixer (i.e., Figure 7B The first mixer uses the TX LO to mix the received filtered signal to obtain an RF signal. The RF signal is coupled through the receiver and output to the TX HD3 calibration circuit (such as Figure 7B The TX HD3 calibration box in FIG. 1 ). The TX HD3 calibration circuit can be regarded as a digital circuit for extracting harmonic information.

[0158] In the receiver, the LNA amplifies the signal output by the transmitter and outputs it to the second mixer (i.e., Figure 7BThe IQ demodulator in the transmitter is used to obtain a demodulated signal, and the demodulated signal is sent to a transimpedance amplifier for amplification. The demodulated signal is then sent to the TX HD3 calibration circuit after passing through the LPF and HPF in sequence, and then through the IQ ADC for analog-to-digital conversion. The TX HD3 calibration circuit extracts the harmonic information in the transmitter from the feedback signal, and converts it into the parameters required to generate the cancellation signal through the upper controller, and provides it to the TX HD3 compensation unit. Among them, the harmonic information obtained by the TX HD3 calibration circuit includes one or more of the following parameters: the initial phase, starting frequency, cutoff frequency, frequency change duration, center frequency, etc. of the harmonic signal (or main frequency signal). The TX HD3 calibration unit or the upper controller determines the parameters used to generate the cancellation signal in the compensation unit according to the harmonic information, such as the initial phase, the frequency of the cancellation signal, the delay, etc.

[0159] It should be noted that the cancellation operations of the third harmonic and / or the fifth harmonic in the above examples may be determined according to the requirements of the transmitter.

[0160] In some optional embodiments, based on the transmitting link of the digital phase shifter architecture described in the embodiment of the present application, when calibrating and compensating the HD3, the main source of the generation of HD3 in the active mixer is the third harmonic in the nonlinearity of V / IConverter, so the HD3 can be calibrated and compensated by the following method: Fig.12 The cubic module-based compensation architecture shown in Fig.13 The compensation structure shown is based on a triple frequency waveform generator.

[0161] Fig.14 FIG. 1 is a schematic diagram of calibration compensation of a transmission link based on a digital phase shifter architecture in an embodiment of the present application. Fig.14 As shown, based on the relevant technical contents of the calibration and compensation operation for IQ Imbalance, LO leakage and HD3 in the embodiment of the present application: the compensation operation for IQ Imbalance can be achieved by compensating the conjugate signal of the BB (baseband) signal to reversely cancel the image component, and this compensation operation mode is not affected by the calibration mode of IQ Imbalance. The compensation for LO Leakage can be achieved by adjusting the DC component (i.e., DC bias) of the IQ two-way, and the calibration mode of LO Leakage has no effect on its compensation scheme. For HD3, since the third-order harmonic distortion of the orthogonal mixer V / I Converter is the main source of HD3, and the harmonic distortion will be affected by the DC bias, when both LO Leakage and HD3 of the transmission link need to be calibrated, it is necessary to calibrate HD3 after calibrating LO Leakage to ensure the accurate performance of HD3 calibration.

[0162] In addition, the compensation methods of HD3 based on the digital pre-compensation architecture of the digital cubic module and the digital pre-compensation architecture based on the frequency doubling waveform generator module will directly affect the subsequent calibration scheme and subsequent compensation process. Specifically:

[0163] In an optional embodiment, for a digital pre-compensation architecture based on a digital cubic module, LO Leakage may be calibrated and compensated first, and then the root cause of the HD3 problem, i.e., the compensation coefficient of HD3, may be calibrated under a stable DC bias; then, IQ Imbalance may be calibrated, and after IQ Imbalance is further compensated, the third harmonic distortion may be compensated for the two IQ paths based on the results of IQ Imbalance pre-compensation.

[0164] In an optional embodiment, for a digital pre-compensation architecture based on a frequency doubling waveform generator module, after calibrating and compensating for LO Leakage, the compensation coefficient of HD3 can be calibrated, and IQImbalance can be calibrated and IQ Imbalance can be compensated under a stable DC bias; subsequently, the third harmonic distortion is compensated for the IQ paths based on the results of IQImbalance pre-compensation according to the results after compensation.

[0165] In another optional embodiment, for a digital pre-compensation architecture based on a frequency doubling waveform generator module, after calibrating and compensating for LO Leakage, the compensation coefficient of HD3 can be calibrated, and IQImbalance can be calibrated and compensated for IQ Imbalance under a stable DC bias; subsequently, the actual waveforms of the IQ and Q signals and the compensation coefficient of HD3 are calculated respectively through the compensation results, and the waveform information of 3x and 5x that need to be pre-compensated is calculated in reverse.

[0166] In another optional embodiment, for the digital pre-compensation architecture based on the frequency doubling waveform generator module, LO Leakage can be calibrated and compensated first, and then the pre-compensation coefficients of HD3 and IQ Imbalance can be calibrated simultaneously through multiple (such as three) observations, and then the pre-compensation coefficients at the HD3 mirror position can be calibrated again through observations (such as two times); finally, the 3-fold and 5-fold frequency coefficients that need to be pre-compensated are calculated back through the pre-compensation coefficients at the HD3 and HD3 mirror positions. It should be noted that the observations in the embodiments of the present application are used to represent operations such as testing and comparative analysis of different test results.

[0167] See also Fig.14It can be seen from the structure shown that the acquisition circuit has two acquisition branches, and the two acquisition branches can be switched dynamically; wherein, the input end of one acquisition branch is connected between the voltage-current converter and the current switch; the input end of the other acquisition branch is connected to the output end of the power amplifier, and the acquisition branch is provided with an IQ demodulator; in addition, Fig.14 In the structure shown, the acquisition circuit is further provided with a multiplexer, wherein the input end of the multiplexer is respectively connected to the output ends of the two acquisition branches, and the output end is used to output the sampling signal.

[0168] exist Figure 12 to Figure 14 In the structure shown, the sampling signal may be an analog signal, that is, the output end of the acquisition circuit is connected to the IQ ADC; or, the sampling signal may be a digital signal, and the acquisition circuit at least includes the IQ ADC.

[0169] It should be noted that when the RF signal sent by the signal transmission link is not an orthogonal signal, Figure 12 to Figure 14 The acquisition circuit can be completed by using non-orthogonal components. For example, a single-ended down-conversion mixer can be used to replace the IQ demodulator, and a single-ended analog-to-digital converter can be used to replace the IQ ADC.

[0170] The following is a circuit scheme provided by this application based on the above examples:

[0171] An embodiment of the present application provides a signal compensation unit, which is applied to a radar, and the compensation unit includes:

[0172] An acquisition circuit is coupled to the signal transmission link, and the acquisition circuit is used to perform an acquisition operation on the signal in the signal transmission link to obtain a sampled signal; wherein the signal transmission link is used to generate a radio frequency signal for radar detection, wherein the radio frequency signal includes a harmonic signal;

[0173] A cancellation signal generator is coupled to the acquisition circuit and the signal transmission link; the cancellation signal generation circuit detects the sampling signal, generates a cancellation signal for canceling the harmonic signal, and outputs the cancellation signal to the signal transmission link.

[0174] An embodiment of the present application provides a transmitter, including:

[0175] A signal transmission link, used to transmit a radio frequency signal for detection;

[0176] The compensation unit is coupled to the signal transmission link.

[0177] In an exemplary embodiment, the signal transmission link includes:

[0178] A first signal generator, used to generate a baseband signal;

[0179] A second signal generator, used for generating a local oscillator signal;

[0180] A mixer, coupled to the first signal generator and the second signal generator, configured to perform up-conversion processing on the baseband signal using the local oscillator signal;

[0181] The power amplifier is coupled to the mixer and is used to amplify the signal output by the mixer to obtain the radio frequency signal.

[0182] The transmitter provided in the embodiment of the present application, by adding a compensation unit in the transmitter, can suppress the harmonic signal in the radio frequency signal by utilizing the cancellation signal output by the compensation unit, reduce the harmonic component in the radio frequency signal, thereby improving the signal quality of the radio frequency signal output by the transmitter, and further improving the receiving performance of the receiver for the radio frequency signal.

[0183] The present application provides a radar chip, which is configured with a device capable of executing the method described above; or includes the transmitter described above.

[0184] The radar chip provided in the embodiment of the present application performs a collection operation on the signal in the signal transmission link to obtain a sampling signal, and uses the sampling signal to generate a cancellation signal, and outputs it to the signal transmission link, so as to use the cancellation signal to suppress the harmonic signal in the radio frequency signal and reduce the harmonic component in the radio frequency signal, thereby improving the signal quality of the radio frequency signal output by the transmitter, and further improving the receiving performance of the receiver for the radio frequency signal.

[0185] It should be noted that the electromagnetic waves in the present application include radio waves and light waves. Radio waves include short waves, medium waves, long waves and microwaves, etc. Microwaves include centimeter waves (i.e. electromagnetic waves from 3 GHz to 30 GHz, such as electromagnetic waves from 3.1 GHz to 10.6 GHz, electromagnetic waves in the 24 GHz frequency band, etc.) and millimeter waves (i.e. electromagnetic waves from 3 0 GHz to 3 00 GHz, such as electromagnetic waves in the 60 GHz frequency band, electromagnetic waves in the 77 GHz frequency band (such as 77 GHz to 81 GHz, etc.)), and light waves may include ultraviolet rays, visible light, infrared rays, and lasers, etc., among which the electromagnetic wave frequency band of lasers is (3.846 to 7.895)*10 5 GHz, that is, laser is included in the ultraviolet and visible light frequency bands.

[0186] The embodiment of the present application also provides an integrated circuit, which may include a radio frequency module, an analog signal processing module and a digital signal processing module connected in sequence; the radio frequency module is used to generate a radio frequency transmission signal and receive a radio frequency reception signal; the analog signal processing module is used to down-convert the radio frequency reception signal to obtain an intermediate frequency signal; the digital signal processing module is used to convert the intermediate frequency signal into an analog-to-digital signal to obtain a digital signal; and the radio frequency module includes any of the above signal transmission links, the above signal transceiver links, any of the above signal calibration links, any of the above signal compensation links, any of the above signal calibration systems, and / or the above IQ mixers; and / or the digital signal processing module compensates in the digital domain based on the above feeder unequal length compensation method; wherein the radio frequency reception signal is an echo signal formed by the radio frequency transmission signal being emitted and / or scattered by the target. Optionally, the integrated circuit may also include a data processing module, which is used to process the digital signal to achieve target detection and / or wireless communication, for example, the integrated circuit may be a millimeter wave radar chip (chip or die).

[0187] In some optional embodiments, the integrated circuit may be an AiP (Antenna-In-Package) chip structure, an AoP (Antenna-On-Package) chip structure, or an AoC (Antenna-On-Chip) chip structure.

[0188] According to other embodiments of the present application, an electromagnetic wave sensor is also proposed. The electromagnetic wave sensor may include an antenna, and an integrated circuit as described above. The integrated circuit is electrically connected to the antenna for receiving and transmitting electromagnetic wave signals. For example, the electromagnetic wave sensor may include: a carrier, an integrated circuit and an antenna as described in any of the above embodiments, and the integrated circuit may be arranged on the carrier; the antenna may be arranged on the carrier, or the integrated circuit may be integrated with the integrated circuit as an integrated device arranged on the carrier (that is, the antenna may be an antenna provided in an AiP, AoP or AoC structure at this time); the integrated circuit is connected to the antenna (that is, the sensor chip or integrated circuit is not integrated with an antenna at this time, such as a conventional SoC, etc.), for receiving and transmitting electromagnetic wave signals. The carrier may be a printed circuit board PCB, and the first transmission line may be a PCB trace.

[0189] An embodiment of the present application provides a device, which may include: a device body; and an electromagnetic wave sensor as described above, which is arranged on the device body; wherein the electromagnetic wave sensor is used for target detection and / or communication to provide reference information for the operation of the device body.

[0190] The embodiment of the present application also provides an electronic device, which can be expressed in the form of a general-purpose computing device. The components of the electronic device may include, but are not limited to: at least one processing unit, at least one storage unit, a bus connecting different system components (including a storage unit and a processing unit), a display unit, etc. Among them, the storage unit stores a program code, and the program code can be executed by the processing unit so that the processing unit executes the method described in this specification according to various exemplary embodiments of the present application. The storage unit may include a readable medium in the form of a volatile storage unit, such as a random access memory unit (RAM) and / or a cache memory unit, and may further include a read-only memory unit (ROM).

[0191] The storage unit may also include a program / utility having a set (at least one) of program modules, such program modules including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.

[0192] The bus may represent one or more of several types of bus structures, including a memory unit bus or memory unit controller, a peripheral bus, an accelerated graphics port, a processing unit, or a local bus using any of a variety of bus architectures.

[0193] The electronic device may also communicate with one or more external devices (e.g., keyboards, pointing devices, Bluetooth devices, etc.), may communicate with one or more devices that enable a user to interact with the electronic device, and / or may communicate with any device that enables the electronic device to communicate with one or more other computing devices (e.g., routers, modems, etc.). This communication may be performed through an input / output (I / O) interface. In addition, the electronic device may also communicate with one or more networks (e.g., local area networks (LANs), wide area networks (WANs), and / or public networks, such as the Internet) through a network adapter. The network adapter may communicate with other modules of the electronic device through a bus. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the electronic device, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems, etc.

[0194] For example, the electronic device in the embodiment of the present application may also include: a device body; and an electromagnetic wave sensor as described in any of the above embodiments arranged on the device body; wherein the electromagnetic wave sensor can be used to realize functions such as target detection and / or wireless communication.

[0195] Specifically, on the basis of the above embodiments, in an optional embodiment of the present application, the electromagnetic wave sensor can be arranged on the outside of the device body, or on the inside of the device body, and in other optional embodiments of the present application, the electromagnetic wave sensor can also be partially arranged on the inside of the device body and partially arranged on the outside of the device body. The embodiments of the present application are not limited to this, and the specific situation may vary. In an optional embodiment, the above-mentioned device body can be a component and product used in fields such as smart cities, smart homes, transportation, smart homes, consumer electronics, security monitoring, industrial automation, cabin detection (such as smart cockpits), medical equipment and health care. For example, the device body can be intelligent transportation equipment (such as cars, bicycles, motorcycles, ships, subways, trains, etc.), security equipment (such as cameras), liquid level / flow rate detection equipment, smart wearable devices (such as bracelets, glasses, etc.), smart home devices (such as sweeping robots, door locks, televisions, air conditioners, smart lights, etc.), various communication equipment (such as mobile phones, tablets, etc.), as well as gates, smart traffic lights, smart signs, traffic cameras and various industrial robotic arms (or robots), etc., and can also be various instruments for detecting life characteristic parameters and various equipment equipped with the instruments, such as life characteristic detection in car cabins, indoor personnel monitoring, smart medical equipment, consumer electronic equipment, etc.

[0196] The embodiment of the present application also provides a non-transitory computer-readable storage medium on which computer-readable instructions are stored. When the instructions are executed by a processor, the processor executes the feeder unequal length compensation method as described above.

[0197] Through the description of the above implementation methods, it is easy for those skilled in the art to understand that the example implementation methods described here can be implemented by software or by combining software with necessary hardware. The technical solution according to the implementation method of the present application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, including several instructions to enable a computing device (which can be a personal computer, a server, or a network device, etc.) to execute the above method according to the implementation method of the present application.

[0198] The software product may use any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, a system, device or device of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination thereof. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0199] Computer readable storage media may include data signals propagated in baseband or as part of a carrier wave, wherein readable program codes are carried. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The readable storage medium may also be any readable medium other than a readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, device, or device. The program codes contained on the readable storage medium may be transmitted using any suitable medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination thereof.

[0200] Program code for performing the operations of the present application may be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In the case of a remote computing device, the remote computing device may be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0201] The computer-readable medium carries one or more programs. When the one or more programs are executed by a device, the computer-readable medium implements the aforementioned functions.

[0202] Those skilled in the art will appreciate that the above modules can be distributed in the device according to the description of the embodiment, or can be changed accordingly and only used in one or more devices different from the embodiment. The modules of the above embodiments can be combined into one module, or further divided into multiple sub-modules.

[0203] According to an embodiment of the present application, a computer program is proposed, including a computer program or an instruction, which, when executed by a processor, can execute the method described above. In an optional embodiment, the above-mentioned integrated circuit can be a millimeter wave radar chip. The type of digital function module in the integrated circuit can be determined according to actual needs. For example, in a millimeter wave radar chip, the data processing module can be used for functions such as distance-dimensional Doppler transform, velocity-dimensional Doppler transform, constant false alarm detection, wave direction detection, point cloud processing, etc., to obtain information such as the distance, angle, speed, height, micro-Doppler motion characteristics, shape, size, surface roughness and dielectric properties of the target.

[0204] It should be noted that radio devices can achieve functions such as target detection and / or communication by transmitting and receiving radio signals to provide the device body with detection target information and / or communication information, thereby assisting or even controlling the operation of the device body.

[0205] For example, when the above-mentioned device body is applied to an advanced driver assistance system (i.e., ADAS), the radio device (such as millimeter-wave radar) as a vehicle-mounted sensor can assist the ADAS system to realize application scenarios such as adaptive cruise control, automatic braking assistance (i.e., AEB), blind spot detection warning (i.e., BSD), assisted lane change warning (i.e., LCA), reversing assistance warning (i.e., RCTA), parking assistance, rear vehicle warning, collision avoidance, pedestrian detection, etc.

[0206] It will be appreciated by those skilled in the art that all or some of the steps, systems, and functional modules / units in the methods disclosed above may be implemented as software, firmware, hardware, and appropriate combinations thereof. In hardware implementations, the division between the functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed by several physical components in cooperation. Some or all components may be implemented as software executed by a processor, such as a digital signal processor or a microprocessor, or implemented as hardware, or implemented as an integrated circuit, such as an application-specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include a computer storage medium (or non-transitory medium) and a communication medium (or temporary medium). As known to those skilled in the art, the term "computer storage medium" includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. In addition, it is well known to those of ordinary skill in the art that communication media typically contain computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

Claims

1. A transmitter, comprising a signal transmission link and a compensation unit; in: The signal transmission link comprises: A first signal generator, used to generate a baseband signal; A second signal generator, used for generating a local oscillator signal; A radio frequency transmitting circuit, connected to the first signal generator and the second signal generator, and configured to output a radio frequency signal for radar detection using the baseband signal and the local oscillator signal; The compensation unit is used to generate a cancellation signal and output it to a signal transmission link to cancel the harmonic signal in the radio frequency signal.

2. The transmitter according to claim 1, It is characterized in that The phase of the baseband signal is adjustable.

3. The transmitter according to claim 2, It is characterized in that The first signal generator comprises: A digital baseband signal source for generating a baseband signal sequence with controlled phase shift in a digital domain; The digital-to-analog converter is connected to the digital baseband signal source, converts the baseband signal sequence into an analog baseband signal and outputs the analog baseband signal.

4. The transmitter according to any one of claims 1 to 3, It is characterized in that The compensation unit comprises: An acquisition circuit, coupled to the radio frequency transmitting circuit, for acquiring a signal in the radio frequency transmitting circuit to obtain a sampling signal; The cancellation signal generator is used to generate the cancellation signal according to the harmonic information carried in the sampling signal.

5. The transmitter according to claim 1, It is characterized in that The device also includes an adder, which is coupled to the compensation unit and the first signal generator and combines the cancellation signal and the baseband signal.

6. The transmitter according to claim 1, It is characterized in that The compensation unit includes at least one of the following: A third harmonic generator, used for generating a third harmonic signal in the cancellation signal; The fifth harmonic generator is used to generate the fifth harmonic signal in the cancellation signal.

7. The transmitter according to claim 1, Features: The compensation unit and the first signal generator are independent of each other.

8. The transmitter according to claim 4, Features: The radio frequency transmitting circuit includes a mixer; The input end of the acquisition circuit is connected to the output end or the signal detection end of the mixer; or, The input end of the acquisition circuit is connected to the RF output end or the RF detection end of the RF transmitting circuit.

9. The transmitter according to claim 4, Features: The acquisition circuit includes: a power detection circuit or a down-mixer.

10. A radar chip, It is characterized in that Comprising a transmitter as claimed in any one of claims 1 to 9.

11. The radar chip according to claim 10, Features: The compensation unit obtains a sampling signal through a BIST module in the radar chip; the compensation unit detects harmonic information in the signal provided by the BIST module and generates a cancellation signal.

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