Research And Implementation On Modem Of Broadband Frequency Hopping Radio

Broadband frequency hopping radio has a multi-band,multi-function,multi-mode characteristics;and has anti-intercepting,interference,high security,and self-networking capabilities,a UAV needs,with a variety of anti-jamming performance new airborne radio interference.The aircraft carrier has a multi-band radio can communicate with other stations and ground to form ad hoc networks,and enables high-speed data transmission and other functions between stations.This paper first wideband frequency hopping radio modem technology research,including research modulation and demodulation method and receiver synchronization of key technologies.For this project the signal bandwidth is 20 MHz,but the need to achieve a broadband 48 MHz frequency hopping modulation and demodulation,in order to achieve better bandwidth utilization,select 8DPSK modulation method,and raised cosine filter is designed to solve the problem of inter-symbol interference,choose a more coherent demodulation differential demodulation method demodulation easy to implement,reducing the design difficulty and cost of the receiver;secondly propose two solutions for the problem of synchronization at the receiving end,one in the capture process by tracking code and carrier ring Central achieve carrier synchronization,and details of the method of capture signal,the energy accumulation method detection method,effectively improve the efficiency of synchronization.Second,using Gardner ring to achieve bit synchronization,error rate and system simulation analysis,and for the presence of timing offset and timing jitter simulation case;Finally,the broadband frequency hopping radio modem designed for the overall program,including the design of the design of the receiver,transmitter and frequency integrated module design.