Analog Phase Shifter And Pulse Compressor(ASPC) Preprocessing System And Integration

Phased array radar has been widely used due to its small size,light weight,and fast scanning speed.If its frequency is increased,it is expected to achieve high detection accuracy and high resolution imaging.However,when the phased array radar operating frequency is raised to a very high frequency band,the direct down conversion in the receiver and the digital sampling in the back-end DSP have great challenges,and the down-conversion power consumption becomes large,and the back-end DSP is difficult to achieve real-time processing.In response to this problem,the project team proposed a new radar receiver link—Analog Shifter and Pulse Compressor(ASPC)signal pre-processing system circuit based on the SIP package integration method.The system is mainly composed of phase shifters and pulses compressor,amplifier,detector circuit,Schmitt trigger composition.This article is based on ASPC signal preprocessing system circuit,mainly to complete the following points:(1)Complete the circuit design work of the ASPC signal preprocessing system,complete the verification of signal integrity in the ADS,and carry out physical verification through the PCB board level.And for the ASPC signal preprocessing circuit,SIP packaging integration through the thin film process in order to achieve circuit miniaturization.(2)Aiming at the important components of the ASPC signal preprocessing system,a 6-T high frequency Schmitt trigger is designed.The Schmitt trigger mainly uses voltage feedback to increase its conversion speed and changes its threshold by changing the substrate bias voltage so that the frequency of the collected input signal reaches 7 GHz.(3)Complete the preliminary design of high-frequency ASPC signal pre-processing circuit and study the detection circuit in the system circuit.This article mainly studies the microstrip filter in the detection circuit.It mainly suppresses the parasitic passband in the stopband by adjusting the length of the transmission line and reducing the characteristic impedance of the low impedance line or increasing the characteristic impedance of the high impedance line.The frequency is 3.5GHz,the insertion loss in the passband is less than 1dB,and the insertion loss is greater than 20 dB in 5.5-15 GHz.The ASPC signal pre-processing radar receiver circuit is different from the traditional radar receiver.The pulse compression signal preprocessing function is extracted from the DSP digital signal processing and completed by the pulse compressor in real time,which relieves the pressure of digital signal processing.It saves a large power consumption and avoids signal distortion due to down conversion.Replacing the ADC with a Schmitt trigger,it reduces the power consumption and increases the speed of the circuit's acquisition of signals in the overall system circuitry.