Millimeter wave time-division passive frequency modulation multichannel colliding-proof radar for car

Abstract

The invention relates to the radio-positioning technical field, particularly a millimeter-wave time-division passive frequency modulation multi-channel automotive anti-collision radar, which is realized through the following steps: adopting the full-phase parameters to receive/transmit reference signals; asynchronously controlling the time division and the time sequence; watching the targets which are prone to collision on the w surface in an omni-directional manner through DSP cyclic scanning wave beams by a quasi-optical dielectric lens antenna circular array; controlling the time division SAW multi-channel passive frequency modulation through road condition cameras, an own vehicle speed, a GPS signal MCU; sending to antenna array to transmit through an up-converter, an amplitude limiter, T/R3, a frequency multiplier and a power amplifier, T/R2, an isolator and a wave beam switch; filtering the returning wave in a conjugating and matching manner with the transmitting SAW through the antenna array, the wave beam switch, the isolator, R/T1, the low-noise high amplifier, a down-converter, a medium amplifier, the time-division circuit and the SAW multi-channel signals; processing and controlling DSP and MCU; controlling the false-alarm when encountering a plurality of road barrier targets DSP and confirming the position, the distance and the relative speed; displaying the three-dimensional image on a CRT, wherein the closer the vehicle gets to the target, the higher the resolution power is; identifying the nearest distance to the vehicle; giving an alarm when the distance is smaller than the safety distance; and intelligently avoiding the barriers or reducing or braking if the distance is close to a risk distance, wherein the control is determined based on the actual condition of the road surface environment combined with the own vehicle speed and the GPS data, thereby improving the travelling safety.

Description

Technical field [0001] The invention relates to the technical field of radio wave transmitting and receiving to detect the position, distance and speed of a target, in particular to a millimeter wave time division passive frequency modulation multi-channel automobile collision avoidance radar. Background technique [0002] At present, the number of motor vehicles such as automobiles and motorcycles has increased in large numbers, roads are congested and overloaded, and frequent car accidents have caused a large number of casualties and major property losses. This has become a serious social problem in the world. The United States, Europe, Japan and other countries have invested a lot of manpower and material resources in the development of advanced anti-collision radars. Because the working environment and conditions of automobile anti-collision radars are very harsh, the time for the collision avoidance process of fast-moving vehicles is extremely short, less than one second, an...

AI Technical Summary

Problems solved by technology

According to the analysis, the anti-collision radar will inevitably encounter the problem of multi-target detection, and the FM-CW frequency modulation continuous wave anti-collision radar is limited to the detection of a single target

The RCS of radar reflection cross sections of different targets is different, the echo delay time of different target distances must be different, and the Doppler frequency shift is also different with different moving speeds. Therefore, the modulated signal only uses a single-frequency periodic signal as a detection mark, which cannot Simultaneous and unambiguous determination of distance and velocity for all targets within the field of view

This kind of anti-collision radar has a single resolution for the size and distance of the target that may collide. The echoes of multiple adjacent targets will intermodulate with each other and crosstalk will make it difficult to distinguish the detection data, which will affect the judgment.

Continuous wave radar has the problem of energy leakage of the transmitting antenna blocking the receiving signal, and the poor isolation of the receiving / transmitting antenna affects the detection, especially the detection of weak targets

Horn-structured antennas have insufficient angular resolution in the horizontal direction, worse when the road is curved, reflective parabolic antennas are slow to scan, anti-vibration and dust-proof, and microstrip antennas have a large loss in millimeter-wave frequencies

The simple radar display lacks the resolution of adjacent targets, cannot display multi-target panoramic image information, and cannot accurately warn of multiple target positions, distances, and relative displacement speeds

Pulse radar has a transmission signal shield, and the echo blind distance is not suitable for cars to avoid collisions at close range

Cars driving on the expressway without the monitoring of rear-view early warning radar often have rear-end collision accidents, and the accident rate is higher when the weather visibility is poor

Existing automotive anti-collision radars lack the function of using sensor signals to form a closed-loop control, lack adaptive control of road environment antennas and intelligent control of automatic obstacle avoidance, deceleration and braking, and cannot help drivers in time to avoid accidents in poor visibility or driving distress situations

Images