CN102866387A - Millimeter wave frequency modulated continuous wave (FMCW) two-unit phased array distance and velocity measurement monolithic radar transceiver - Google Patents

Abstract

The millimeter-wave FMCW two-unit phased array ranging and speed-measuring single-chip radar transceiver belongs to the field of ranging and speed-measuring radar transceivers, and is characterized in that it is composed of an FMCW transmitting module, a two-unit receiving module, a digital control module and a bias generating module. The transmitting module is used to generate FMCW continuous wave modulation signal, which is amplified and transmitted through the antenna. The two-unit receiving module is used to process the signal reflected from the target. The digital control module is used to control the configurable quantities inside the system. The sweep period, sweep bandwidth, transmit signal power, receive branch gain, fifth-order Butterworth low-pass filter bandwidth, and phase shift value of the phase shifter can all be configured for FMCW modulated signals, and can be applied to Detection of targets at close range, long range and different angles.

Description

Millimeter wave FMCW two unit phased array ranging and range rate monolithic radar transceivers

Technical field

The invention belongs to ranging and range rate radar transceiver field, refer more particularly to the employing continuous wave that works in millimeter wave band that adopts the circuit of single-chip integrated technology to realize and modulate the radar transmit-receive device that the two unit phased arrays of (FMCW) mode receive.

Background technology

The present frequency range of millimeter wave is 30GHz ~ 300GHz, and its wavelength is in the scope of 1mm ~ 10mm.Because the singularity of its wavelength, millimeter wave have unique character, with submillimeter wave, infrared until visible light frequency band is compared, millimeter wave is decayed very little in the environment such as cigarette, mist, cloud, sandstorm.Therefore under the scene of many infrared and visible light detecting devices cisco unity malfunctions, millimeter wave still can work, thereby can greatly improve millimeter wave detection equipment to the adaptability of complex environment.Because these characteristics of millimeter wave, its application aspect radar has larger advantage.

Millimetre-wave radar can be applied in the automobile collision avoidance radar aspect, and automobile collision avoidance radar is by detecting distance and the speed of the place ahead target, when detected value just sends early warning or forces treatment measures, the possibility that occurs to reduce car accident not in normal range the time.Automobile collision avoidance radar is installed in the place ahead of automobile, must adapt to the road conditions of various complexity, can be under various environment the target of inspection department's vehicle front.Compare radar for backing car and backsight radar, harsher to the requirement of automobile collision avoidance radar: requirement can be investigated all motion and standstill targets of front region; Requirement has enough dynamic ranges, can detect the target with different radar cross sections of different distance; Generally speaking require the systemic effect distance about 300m; The response time of system must be enough fast, otherwise may because system responses is too slow, also have little time reaction even made the early warning driver; System is little, is convenient to install onboard.Millimetre-wave radar is because its stable detection performance under various complex environments is the preferably selection that realizes automobile collision avoidance radar.The frequency range that millimetre-wave radar mainly uses is 77GHz.77 ~ 91GHz was distributed to the super bandwidth radar of millimeter wave in 2005 in Europe, and the short distance radar of original frequency range 21.65 ~ 26.65GHz was all withdrawn from the market before 2013, left the development transitional period in 8 years of millimetre-wave radar for.

Most of millimetre-wave radar that existing market exists all adopts discrete microwave component to realize that its volume is larger and expensive, has limited being widely used of millimetre-wave radar.Adopt integrated circuit technique with its integrated be a feasible scheme that solves its Cost Problems.The progress of integrated circuit fabrication process provides this kind possibility for people.So far, the transistorized cutoff frequency of CMOS technique has surpassed 200GHz, and it is feasible to adopt such technique to carry out the design office of millimetre-wave radar.In order to obtain high-gain, the antenna beam of millimetre-wave radar is often narrower, only can detect the target in certain low-angle, and for example, the antenna beam of millimeter-wave automotive forward direction collision avoidance radar is generally about 15 degree.If phased-array technique is applied to millimetre-wave radar, so that its wave beam can carry out the scanning of angle under control, can expand greatly like this range of application of millimetre-wave radar.

The present invention proposes a kind of two unit phased array millimetre-wave radar systems that adopt the circuit of single-chip integrated technology to realize, this system adopts the modulation system of continuous wave frequency (FMCW), distance and speed that can measurement target, simultaneously, this system has two-way and receives path, by at internal system design phase shifter, can realize the phased-array receiver of Unit two, realize the beam coverage of 180 degree.Internal system has a plurality of configurable parameters, can independently be configured according to needed measurement range and precision, thereby greatly improve the range of application of this system.The technology that adopts circuit of single-chip integrated also can be brought advantage on cost and the volume to this system.

Summary of the invention

The object of the invention is to propose a kind of two unit phased array ranging and range rate monolithic radar systems of the FMCW of employing modulation system, it is characterized in that comprising: the transmitter module of continuous wave modulation system, hereinafter to be referred as FMCW transmitter module, two unit receiver modules, digital control module and biasing generation module, wherein:

The FMCW transmitter module is for generation of the FMCW modulation signal, successively after the 3rd buffer amplifier, power amplifier PA amplify, go out through transmission antennas transmit again, described FMCW transmitter module comprises: phase-locked loop pll, power amplifier PA and buffer amplifier BUF1 ~ BUF3, wherein:

Phase-locked loop pll, hereinafter to be referred as phaselocked loop, comprise: phase frequency detector PFD, hereinafter to be referred as phase frequency detector, charge pump CP, hereinafter to be referred as charge pump, loop filter LOOP FILTER, hereinafter to be referred as loop filter, voltage controlled oscillator VCO, hereinafter to be referred as voltage controlled oscillator, four of 1/2 frequency division frequency divider DIV1 ~ DIV4 successively, the frequency divider DIV5 of 16 ~ 23 configurable integral frequency divisioils and DELTA-SIGMA modulator DSM, hereinafter to be referred as modulator, wherein, described phase frequency detector, charge pump, loop filter, voltage controlled oscillator and five frequency divider DIV1 ~ DIV5 are concatenated into ring-type successively, the first input end input reference frequency F_REF signal of described phase frequency detector, the second input end then links to each other with fractional frequency signal output terminal behind the 5th the frequency divider DIV5 frequency division, the division control signal input end of described five frequency divider DIV5 links to each other with the modulation signal output terminal of modulator, the output terminal of described voltage controlled oscillator connects the first buffer amplifier BUF1 and the 3rd adjustable buffer amplifier BUF3 of gain amplifier successively

Power amplifier PA, input end links to each other with the output terminal of described the 3rd buffer amplifier BUF3, and the FMCW modulation signal that is used for producing carries out power amplification, goes out by transmission antennas transmit again;

Two unit receiver modules are used for the echo that receives is carried out down coversion, amplification and filtering, are converted to digital signal for outside digital processing section processes again, and described two unit receiver modules comprise:

The low noise amplifier that two-way is parallel, respectively with LNA1 and LNA2 represent, two-way is parallel frequency mixer, respectively with MIXER1 and MIXER2 represent, two-way is parallel phase shifter, respectively with PHASE SHIFTER1 and PHASE SHIFTER2 represent, three buffer amplifiers, respectively with BUF2, BUF4 and BUF5 represent, trans-impedance amplifier, with TIA represent, Analog Baseband part and digital to analog converter ADC, wherein:

The low noise amplifier that two-way is parallel is used for two paths of signals RXIN_1 and the RXIN_2 that receives from receiving antenna amplified, with the noise of compacting subsequent module, to the parallel frequency mixer of described two-way corresponding input signal is provided,

The frequency mixer that two-way is parallel carries out obtaining intermediate-freuqncy signal after the mixing to the signal of input respectively, and this frequency mixer is passive frequency mixer, is connected between the anode of the difference output of two frequency mixer, also be connected between the negative terminal of difference output,

Five buffer amplifiers, wherein, the input of the second buffer amplifier BUF2 links to each other with the output terminal of the first buffer amplifier BUF1, after the local oscillation signal that the described FMCW transmitter module of input is produced carries out Hyblid Buffer Amplifier, be sent to simultaneously the input end of the 4th buffer amplifier BUF4 and the 5th buffer amplifier BUF5, respectively hang oneself respectively to amplify and be sent to respectively corresponding the first phase shifter PHASE SHIFTER1 and the second phase shifter PHASE SHIFTER2 afterwards

The phase shifter that two-way is parallel, respectively the conversion of single-ended-to-difference is carried out in the local oscillation signal of the separately described FMCW transmitter module generation of input, under the control of the first phase-shifted control signal PHASE CTRL1, the second phase-shifted control signal PHASE CTRL2 that input, finish phase shift function respectively simultaneously, the result exports to corresponding the first frequency mixer MIXER1 and the second frequency mixer MIXER2, described two phase-shifted control signal PHASE CTRL1, PHASE CTRL2 cover respectively 360 degree scopes from described digital control module.

Trans-impedance amplifier, represent with TIA, consisted of by trsanscondutance amplifier OTA and two feedback resistance RES1, RES2, positive and negative two input ends of the OTA of the described trsanscondutance amplifier respectively positive-negative output end corresponding with the parallel frequency mixer of described two-way are connected, and the current signal of its output is converted into voltage signal

The Analog Baseband part, comprise: three programmable gain amplifier PGA1 ~ PGA3, five rank Butterworth LPF LPF and three DC maladjustment are eliminated feedback module DCOC1 ~ DCOC3, wherein: the gain of described three programmable gain amplifiers sets gradually and is 6dB, 12dB, 18dB or 24dB, the bandwidth of described five rank Butterworth LPF sets gradually and is 200kHz, 500kHz, 1MHz or 2MHz, the first programmable gain amplifier PGA1, five rank Butterworth LPF LPF, the second programmable gain amplifier PGA2 and the 3rd programmable gain amplifier PGA3 connect successively, the described first input end that becomes gain amplifier PGA1 is connected with the output terminal of trsanscondutance amplifier OTA, the output of described PGA3 is connected to the input end of digital-to-analogue conversion ADC, the input end that the first DC maladjustment is eliminated feedback module DCOC1 is connected with the output terminal of described five rank Butterworth LPF, the output terminal that described the first DC maladjustment is eliminated feedback module DCOC1 links to each other with the input end of the first programmable gain amplifier PGA1, the input end that the second DC maladjustment is eliminated feedback module DCOC2 is connected with the output terminal of the second programmable gain amplifier PGA2, the output terminal that described the second DC maladjustment is eliminated feedback module DCOC2 links to each other with the input end of the second programmable gain amplifier PGA2, the input end that the 3rd DC maladjustment is eliminated feedback module DCOC3 is connected with the output terminal of the 3rd programmable gain amplifier PGA3, the output terminal that described the 3rd DC maladjustment is eliminated feedback module DCOC3 links to each other with the input end of the 3rd programmable gain amplifier PGA3, thereby realizes the inhibition to the DC maladjustment of whole reception path;

Digital control module, for described external digital processing section provides interface, and all configurable variablees are controlled, comprise: the phase shift value of the gain of the frequency sweep cycle of described FMCW modulation signal, frequency sweep bandwidth, the power that transmits, receiving branch, the bandwidth of five rank Butterworth LPF and phase shifter, described digital control module comprises: serial data interface, with SPI represent, register file and triangular-wave generator, wherein:

Serial data interface, be used for communicating by letter with described external digital processing section, control signal is write internal register stack, the input end of described serial data interface is respectively external clock CLK, external status upset clock sclk, outside chip selection signal SCS and external series input data SDI, the first output terminal of described serial data interface is serial data output terminal SDO, the second output terminal of described serial data interface is connected to the input of register file, the numerical value that is used for the register-stored of control register heap

Register file, be used for the state of control triangular-wave generator and for this reason all configurable variablees of radar control is provided, comprise: the frequency sweep cycle of described FMCW modulation signal, the frequency sweep bandwidth, the power that transmits, the gain of receiving branch, the phase shift value of the bandwidth of five rank Butterworth LPF and phase shifter, the input end of described register file is connected with the output terminal of serial data interface, the output terminal of described register file is connected with the control end of the input end of triangular-wave generator and all the other configurable variablees

Triangular-wave generator, for generation of the triangular wave waveform, control signal is provided for the modulator in the FMCW transmitter module, thereby produce the signal of FMCW continuous wave modulation, the input end of described triangular-wave generator is connected with register file, and the input end of the modulator in the output terminal of described triangular-wave generator and the FMCW transmitter module is connected;

The biasing generation module is for millimeter wave FMCW two unit phased array ranging and range rate monolithic radar transceivers provide required bias voltage and bias current.

Ranging and range rate monolithic radar system of the present invention, its advantage first is to adopt the circuit of single-chip integrated technology to realize, the size of system is little and cost is low, second is and can many system indexs wherein be configured, at transmitter section, the frequency sweep cycle of FMCW modulation signal, the frequency sweep bandwidth, and the power that transmits can be configured; At receiver section, the gain of receiver, intermediate-frequency bandwidth, the phase shifter angle can be configured, thus this system can be applied to closely, the detection of the target of remote and different angles, can realize different precision for different application.

Description of drawings

Fig. 1 is the structural drawing of millimeter wave FMCW two unit phased array ranging and range rate monolithic radar systems.

Fig. 2 is an embodiment of millimeter wave FMCW two unit phased array ranging and range rate monolithic radar systems.

Fig. 3 is the schematic diagram that the FMCW modulation signal is realized ranging and range rate.

Fig. 4 is the schematic diagram of phased-array receiver.

Embodiment

The present invention is comprised of FMCW transmitter module, two unit receiver modules, digital control module and biasing generation module.The FMCW transmitter module mainly is made of the phase-locked loop pll and the power amplifier PA that produce the FMCW modulation signal again; Two unit receiver modules mainly are made of with MIXER2 phase shifter PHASE SHIFTER1 and PHASE SHIFTER2, Analog Baseband part and the digital to analog converter ADC parallel with two-way with LNA2, the parallel frequency mixer MIXER1 of two-way the parallel low noise amplifier LNA1 of two-way.

In Fig. 2, provided an embodiment of this ranging and range rate monolithic radar system.This embodiment comprises three parts, antenna part, ranging and range rate monolithic radar pack and digital processing baseband portion.Wherein, antenna part comprises two receiving antenna RX_ANT_1 and RX_ANT_2 and an emitting antenna TX_ANT, and the digital processing baseband portion comprises steering logic, FFT conversion, the control of SPI interface, amplitude detection and apart from the velocity information processing logic.The course of work of this embodiment can be described below: digital baseband produces the cycle of FMCW waveform control signal control FMCW continuous frequency modulation and the bandwidth of frequency sweep, offer triangular-wave generator module TRI GEN in the ranging and range rate radar by digital control interface, then the triangular-wave generator module produces a digital triangular signal and offers the DELTA-SIGMA modulator block, thereby controlled the fractional frequency division ratio of phase-locked loop pll, thereby produce a frequency sweep bandwidth and cycle in check millimeter wave FMCW signal all at the output terminal of VCO, this signal offers power amplifier P through a part after the Hyblid Buffer Amplifier), launch the above-mentioned i.e. emission process of embodiment for this reason through emitting antenna TX_ANT; Transmit and after running into target, be reflected back receiving antenna RX_ANT_1 and RX_ANT_2, amplify through the two-way low noise amplifier respectively after entering internal system, carry out mixing by the local oscillation signal after frequency mixer and the phase shift, local oscillation signal is provided by aforementioned PLL, thereby the intermediate-freuqncy signal of obtaining, intermediate-freuqncy signal is through low-pass filter filtering, bandwidth can be configured to 200kHz, 500kHz, 1MHz or 2MHz, amplify through programmable gain amplifier again, its gain is disposed automatically according to the testing result of digital baseband amplitude detection module, so that its gain is in a suitable scope, the most laggard ADC that crosses is converted into 8 position digital signals and enters digital baseband part, the above-mentioned i.e. receiving course of embodiment for this reason; Digital signal enters after the digital baseband, conversion is converted to frequency domain through FFT, it is carried out amplitude detection, and draw the distance of target and the information of speed by certain processing, the result of amplitude detection generates corresponding controlled quentity controlled variable by steering logic, write ranging and range rate monolithic radar transceiver internal system by the SPI interface, what change its inside is configured to adapt to current applied environment, the above-mentioned digital baseband signal processing procedure that is.

This ranging and range rate radar system adopts the continuous wave modulation scheme of FMCW to carry out the measurement of distance and speed, and its principle is explained as follows:

The frequency that the FMCW modulation produces is in time the triangular wave shape and changes, as shown in Figure 3.If the FMCW frequency sweep cycle is T _m, the frequency sweep bandwidth range is BW.For static target, establishing target range is R, mistiming Δ t=2R/c between the modulation waveform that produces of target reflection echo and local oscillator so, and wherein c is the light velocity.

The intermediate-freuqncy signal frequency and the target range that produce after the mixing so have following relation,

$\begin{array}{c}{f}_{\mathrm{IF}}=\frac{2\mathrm{BW}}{T_m}\frac{2R}{c},\\ R=\frac{f_{\mathrm{IF}}c{T}_m}{4\mathrm{BW}}\end{array}$

Because the triangular voltage sweep cycle is about 2ms, and target is returned the time difference ns magnitude is only arranged, thus after the mixing in the middle of the intermediate-freuqncy signal that section depression can ignore.For static target, can regard target range and IF-FRE linear dependence as, measure IF-FRE by the FFT conversion and can obtain target range.

For the target in the motion, because Doppler shift, the echo frequency that rises cycle and decline cycle at triangular wave has difference, can determine the speed of moving target according to this frequency difference, and establishing two frequencies that obtain after the mixing is f ₁And f ₂, speed formula is as follows so:

$v=\frac{c|f_1-{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA00002262639600011.png,HDA00002262639600021.png"\; state="\{\{state\}\}">f</figure-callout>}}_2|}{2f_0}$

F wherein ₀Be FMCW frequency sweep centre frequency.According to above-mentioned two formula, can determine target and the speed of object.The distance of target and the computation process of the speed digital baseband part outside sheet realizes.

This ranging and range rate radar adopts the phased array of Unit two to receive structure, and the phase shifter by internal system carries out phase shift to local oscillation signal, and two-way is synthetic through the signal after the mixing, can equivalence goes out the synthetic wave beam of different directions.The principle of two unit phased arrays is soluble as follows:

Shown in Figure 4 is the antenna of N cell formation, equidistantly arranges in a line along the y axle, and the antenna element spacing is d.Suppose that each antenna element all is identical omnidirectional antenna.

Phased array antenna receives many paths, and every path all is connected on the antenna element.Each antenna element independently receives the electromagnetic wave of coming from far-field radiation, can be approximated to be plane wave under the condition in far field.When certain incident angle was arranged, the time that electromagnetic wave arrives each antenna element was different.Phased array compensated the time interval that each antenna element receives signal, and it is identical to arrive front each the road signal phase of totalizer, is strengthened so mutually the reception to this direction signal.The signal of other directions interferes to be inhibited after totalizer because each road phase place is different mutually.

If carrier frequency is ω _cPlane wave incide on the aerial array, with the normal angle of array plane be θ, the distance between the aerial array is d.Then receive the phase differential of signal between the adjacent antenna array element

For

λ wherein _cBe the incident electromagnetic wave wavelength, c is the light velocity.Being set to the signal that reaches first antenna is

Wherein A and Be incoming signal amplitude and phase place, as carrier frequency ω _cDuring much larger than the frequency of modulation signal, in the short time A and

Can be considered as constant.Then k antenna element reception signal is

Phase-shifting unit compensates the phase place of each road signal, establishes k road signal phase shift value for being k Δ φ, then finally by crossing addition signal afterwards is

When the phase shift value of phase shifter compensates the phase differential that incident angle causes just, namely

$\mathrm{k\&Delta;\&phi;}=k\frac{{\mathrm{\&omega;}}_{c}d\sin \mathrm{\&theta;}}{c}=\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="HDA00002262639600011.png,HDA00002262639600021.png"\; state="\{\{state\}\}">k</figure-callout>}\frac{2\mathrm{\&pi;d}}{\mathrm{\&lambda;}}\sin \mathrm{\&theta;}$

The time, addition output obtains maximal value.So the phased array antenna main beam direction is

${\mathrm{\&theta;}}_{\max }=\arcsin \left(\frac{\mathrm{\&lambda;}}{2\mathrm{\&pi;d}}\mathrm{\&Delta;\&phi;}\right)$

So the phase difference φ in the change battle array between the adjacent cells just can change the sensing of phased array antenna main beam.

The above-mentioned ultimate principle that is phased-array receiver.In the present invention, the position of phase shifter is positioned at the local oscillator end, and local oscillator is carried out phase shift, after the frequency mixer mixing, can access the Phasing of equivalence.The advantage of carrying out phase shift at the local oscillator end is can not introduce extra loss to radio frequency path.

Claims (1)

1. The millimeter-wave FMCW two-unit phased array range-finding and speed-measuring single-chip radar transceiver is characterized in that it includes: a transmitting module of a continuous wave modulation mode, hereinafter referred to as an FMCW transmitting module, a two-unit receiving module, a digital control module and a bias Produces modules where: The FMCW transmitting module is used to generate the FMCW modulated signal, which is amplified by the third buffer amplifier and the power amplifier PA in turn, and then transmitted through the transmitting antenna. The FMCW transmitting module includes: a phase-locked loop PLL, a power amplifier PA and a buffer amplifier BUF1~BUF3, where: Phase-locked loop PLL, hereinafter referred to as phase-locked loop, includes: phase frequency detector PFD, hereinafter referred to as frequency detector, charge pump CP, hereinafter referred to as charge pump, loop filter LOOP FILTER, hereinafter referred to as loop filter , Voltage controlled oscillator VCO, hereinafter referred to as voltage controlled oscillator, four frequency dividers DIV1~DIV4 with 1/2 frequency division in turn, 16~23 frequency divider DIV5 with integer frequency division and DELTA-SIGMA modulator DSM , hereinafter referred to as the modulator, wherein the frequency and phase detector, charge pump, loop filter, voltage controlled oscillator and five frequency dividers DIV1~DIV5 are sequentially connected in series to form a ring, and the frequency and phase The first input terminal of the frequency divider inputs the reference frequency F_REF signal, and the second input terminal is connected to the output terminal of the frequency division signal after the frequency division of the fifth frequency divider DIV5, and the frequency division control signal input of the fifth frequency divider DIV5 is end is connected with the modulation signal output end of the modulator, and the output end of the voltage-controlled oscillator is connected with the first buffer amplifier BUF1 and the third buffer amplifier BUF3 with adjustable amplification gain in turn, Power amplifier PA, the input terminal is connected with the output terminal of the third buffer amplifier BUF3, and is used to amplify the power of the FMCW modulation signal generated, and then transmit it through the transmitting antenna; The two-unit receiving module is used to down-convert, amplify and filter the received echo, and then convert it into a digital signal for processing by an external digital processing part. The two-unit receiving module includes: Two parallel low noise amplifiers, represented by LNA1 and LNA2, two parallel mixers, respectively represented by MIXER1 and MIXER2, two parallel phase shifters, respectively represented by PHASESHIFTER1 and PHASE SHIFTER2, three buffer amplifiers , respectively represented by BUF2, BUF4 and BUF5, transimpedance amplifier, represented by TIA, analog baseband part and digital-to-analog converter ADC, where: Two parallel low-noise amplifiers are used to amplify the two signals RXIN_1 and RXIN_2 received from the receiving antenna to suppress the noise of the subsequent modules, and provide input signals to the two parallel mixers correspondingly, Two parallel mixers respectively mix the input signal to obtain an intermediate frequency signal. The mixers are passive mixers, and the positive terminals of the differential outputs of the two mixers are connected. The negative terminals of the output are also connected between, Five buffer amplifiers, wherein the input of the second buffer amplifier BUF2 is connected to the output terminal of the first buffer amplifier BUF1, after the local oscillator signal generated by the input FMCW transmitting module is buffered and amplified, it is simultaneously transmitted to the fourth buffer amplifier The input ends of BUF4 and the fifth buffer amplifier BUF5 are sent to corresponding first phase shifter PHASESHIFTER1 and second phase shifter PHASE SHIFTER2 respectively after being respectively amplified, Two parallel phase shifters respectively perform single-ended to differential conversion on the local oscillator signals generated by the FMCW transmitting modules respectively inputted, and at the same time respectively input the first phase-shift control signal PHASE CTRL1 and the second phase-shift control signal The phase shifting function is completed under the control of the signal PHASE CTRL2, and the result is output to the corresponding first mixer MIXER1 and the second mixer MIXER2, and the two phase shifting control signals PHASE CTRL1 and PHASE CTRL2 come from the digital control modules, respectively covering a 360-degree range. The transimpedance amplifier, represented by TIA, is composed of a transconductance amplifier OTA and two feedback resistors RES1 and RES2. The positive and negative input terminals of the OTA of the transimpedance amplifier correspond to the two parallel mixers respectively. The positive and negative output terminals are connected, and the current signal output by it is converted into a voltage signal, The analog baseband part includes: three programmable gain amplifiers PGA1~PGA3, fifth-order Butterworth low-pass filter LPF, and three DC offset elimination feedback modules DCOC1~DCOC3, wherein: the gains of the three programmable gain amplifiers Set to 6dB, 12dB, 18dB or 24dB in turn, the bandwidth of the fifth-order Butterworth low-pass filter is set to 200kHz, 500kHz, 1MHz or 2MHz in turn, the first programmable gain amplifier PGA1, the fifth-order Butterworth low-pass The filter LPF, the second programmable gain amplifier PGA2 and the third programmable gain amplifier PGA3 are connected sequentially, the input end of the first variable gain amplifier PGA1 is connected with the output end of the transconductance amplifier OTA, the PGA3 The output is connected to the input end of the digital-to-analog conversion ADC, the input end of the first DC offset elimination feedback module DCOC1 is connected to the output end of the fifth-order Butterworth low-pass filter, and the first DC offset elimination feedback module The output end of DCOC1 is connected to the input end of the first programmable gain amplifier PGA1, the input end of the second DC offset elimination feedback module DCOC2 is connected to the output end of the second programmable gain amplifier PGA2, and the second DC offset elimination feedback module The output end of DCOC2 is connected with the input end of the second programmable gain amplifier PGA2, the input end of the third DC offset elimination feedback module DCOC3 is connected with the output end of the third programmable gain amplifier PGA3, and the third DC offset elimination feedback module The output terminal of DCOC3 is connected to the input terminal of the third programmable gain amplifier PGA3, thereby realizing the suppression of the DC offset of the entire receiving path; The digital control module provides an interface for the external digital processing part, and controls all configurable variables, including: the sweep period of the FMCW modulation signal, the sweep bandwidth, the power of the transmitted signal, the gain of the receiving branch, The bandwidth of the fifth-order Butterworth low-pass filter and the phase shift value of the phase shifter, the digital control module includes: serial data interface, represented by SPI, register file and triangular wave generator, wherein: The serial data interface is used to communicate with the external digital processing part, and the control signal is written into the internal register file. The input terminals of the serial data interface are respectively the external clock CLK, the external state reversal clock SCLK, and the external chip select signal SCS and external serial input data SDI, the first output of the serial data interface is the serial data output SDO, and the second output of the serial data interface is connected to the input of the register file for controlling the register Values stored in registers in the heap, The register file is used to control the state of the triangular wave generator and provide control for all configurable variables in this radar, including: the sweep period of the FMCW modulation signal, the sweep bandwidth, the power of the transmitted signal, the gain of the receiving branch, The bandwidth of the fifth-order Butterworth low-pass filter and the phase shift value of the phase shifter, the input end of the register file is connected with the output end of the serial data interface, and the output end of the register file is connected with the output end of the triangular wave generator The input terminal and the control terminal of other configurable variables are connected, The triangular wave generator is used to generate the triangular wave waveform, and provides control signals to the modulator in the FMCW transmitting module, thereby generating the signal of the FMCW continuous wave modulation, the input end of the triangular wave generator is connected with the register file, and the triangular wave generator The output end of FMCW is connected with the input end of the modulator in the FMCW transmitting module; The bias generating module provides the required bias voltage and bias current for the millimeter-wave FMCW two-unit phased array ranging and speed measuring single-chip radar transceiver.

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