Research On Data Driven Frequency-Hopping OFDM Information Transmission Method

With the increasingly complex electromagnetic environment of the modern information battlefield and the continuous upgrading of communication jamming equipment,the confrontation and game between the enemy and us face great challenges.UAV is widely used because of its advantages in information transmission,mobility and cost.Frequency-Hopping Orthogonal Frequency-Division Multiplexing(FH-OFDM)data link information transmission technology,a typical representative of the data link,is still possible to be detected because it generates frequency hopping patterns through the existence of periodic pseudo-random sequences,thus increasing the risk of signal interference.Therefore,this paper mainly studies how to improve the security,concealability and anti-interference of UAV FH-OFDM data link information transmission.Aiming at the problem that frequency-hopping patterns in traditional FH-OFDM information transmission methods are easy to be detected,on the basis of in-depth analysis of FH-OFDM information transmission method and Message Driven Frequency Hopping(MDFH)technology,this paper proposes a Data Driven Frequency Hopping OFDM(DDFH-OFDM)information transmission method.Combining the idea of message-driven frequency hopping technology in FH-OFDM system,the source data is divided into regular data bits and carrier data bits.On the basis of taking the regular data bit as the first dimension data for subcarrier frequency-hopping OFDM modulation,the idea of sequence cipher is incorporated,and the carrier data bit is taken as the second dimension data after random disturbance processing to control the selection of the subcarrier.A frequency transfer packet mapping rule is designed,which can realize the hidden data transmission and improve the anti-jamming performance in the communication process.The results show that DDFH-OFDM improves the signal-to-noise ratio by 5.2 d B and 2.5 d B compared with OFDM and FH-OFDM respectively.Aiming at the problem that RF fixed frequency modulation in military scene is difficult to meet the requirement of high anti-jamming,a second frequency hopping is designed in RF terminal,and a Data Driven Double Frequency-Hopping OFDM(DDFH-RFH-OFDM)information transmission method is proposed.Through the MATLAB simulation platform,the bit error performance under different order modulation and doppler frequency shift was tested,and simulate and analyze its anti-full-band and anti-part-band jamming and the most commonly used comb jamming by non-partners.The results show that this method has better security,concealment and anti-jamming performance than the traditional FH-OFDM information transmission method.