The Research Of The RF Channel Of Multi-array Adaptive Processing Antenna

"Compass II"(BD-2) satellite positioning system is a new generation of satellitenavigation systems which was independently developed by china. After the completionof the Compass II navigation system, it will be able to provide navigation andpositioning, velocity and timing features as to GPS, GLONASS system. Currently,there are two problem in receiver of the satellite navigation system: one is the satellitesignal which reach the ground is too weak; the other is the receiver is too vulnerable tobe affected by the oppressive RF interference. For my country, the most relevantanti-jamming measure is the use of multi-element adaptive processing antennainterference program. The whole anti-jamming system is mainly made up by fourmodules: four-element antenna array, RF receiving unit, adaptive digital signalprocessing unit, the signal recovery unit.This thesis is design for the RF receiving unit and signal recovery unit of thefour-element adaptive processing antenna system to BD-2(B3) band (center frequency1268.52MHz). It mainly includes four receive channel of frequencies B3,up-conversion channel of B3, the local oscillation circuit, a clock circuit and so on.Because the four-element antenna array will receive different interference signallevel either in band or out of the band, Therefore, how to ensure each receiver channelwith high sensitivity, excellent selectivity and dynamic performance, and ensure theconsistency of the gain and phase among the four receive channels at the same time,will be the key to the design of the entire radio frequency unit and the premise tomaximize the anti-jamming performance of the algorithm. The core content of thisresearch lies in this.This thesis consider the design of multi-channel RF channel according to theproposed anti-jamming indicators mainly based on the entire system, which includeestimates and distribution channel indicators of various parameters, and study the gain,noise figure, linearity, phase noise, amplitude and phase coherence indicators ofanti-jamming performance. Taking into account the compact design, this article uses asimple phase-shift network and a variable gain network to correct the amplitude and phase consistency between each channel. This article not only research the overalldesign of channel, but also study the design of low-noise amplifiers and low phasenoise PLL frequency source. Since the phase noise of the local oscillator signal willdirectly affect the performance of the entire RF channel. PLL frequency synthesizer iswidely used in local oscillator frequency source in modern communication and radarequipment because of its flexible application and wide frequency range. This studydesign two PLL frequency synthesizers as the local oscillator of RF receiver unit andup-conversion unit, and do a more detailed analysis of the phase noise of the PLL.Finally, the channels have been used in adaptive array antenna interference system,through separate radio channel units test, it proved the RF channels meet the electricalproperties of the system, and achieve the design goals.