| In recent years,domestic traffic safety issues have received more and more attention.Some new car systems such as smart driving enter people’s sight The anti-collision system based on radar technology has become a research direction with great development potential.Most vehicle anti-collision radars are millimeter-wave radars,of which the technology is in the hands of foreign giants.China’s millimeter wave radar research is slow to develop due to constraints.In this dilemma,this paper proposes the design and implementation method of the vehicle anti-collision radar system in the 5.8 GHz ISM band.The main research contents and results of this paper are:1.The working method of the vehicle anti-collision radar system is determined as a linear frequency modulated continuous wave.The main parameters of the radar are determined according to the requirements of radar detection capability and radar detection range,such as radar waveform modulation period and transmitting power and receiver sensitivity,etc.2.In order to realize the radar transmitter that meets the transmission power requirement,the phase-locked loop chip with waveform generation function is used to construct the phase-locked loop frequency synthesizer circuit as the linear chirp source of the radar,and phase noise performance and time domain response of the chirp source are tested by the FSW signal and the spectrum analyzer.A proper power amplifier is selected to meet the gain requirement.A Wilkinson power splitter is simulated and implemented.Test results indicate that both the power amplifier and the power splitter meet the design requirements.The radar transmitter consisting of a frequency modulated signal source,a power amplifier and a power splitter meet the design specifications.3.In order to realize the receiver,ADS and Sonnet software were used to simulate and design the low noise amplifier and microstrip bandpass filter that meet the requirements.The circuit simulation flow and adjustment method were introduced in detail.The simulation results all meet the design indicators.A suitable integrated double balanced mixer is selected and tested for its conversion loss.Finally,the sensitivity of the radar receiver is estimated to be-102.7dBm through the circuit simulation results. |
