Title :
Parameter Design and Frequency Synchronization for an OFDM Based HF Modem
Author :
Niu Qunshan ; Ye Zhihui ; Tian Weixing ; Shen Zhongliang
Author_Institution :
Nat. Mobile Commun. Res. Lab., Southeast Univ., Nanjing
Abstract :
With Orthogonal Frequency Division Multiplex (OFDM), a new implementation of the parallel HF modem specified in MIL-STD-188-110B is discussed. The key parameters are analyzed in detail and the analog quadrature modulation and demodulation modules in typical OFDM systems are simplified through Hilbert transform. In addition, the frequency offset estimation method based on short training sequences or several identical parts in one OFDM symbol is introduced and generalized to be used on several identical parts in more than one OFDM symbols. Moreover, an improved method with favorable MSE and twice estimation range of the former one is given, with the same training sequence length. It is shown that the modified method can also be used in other OFDM systems.
Keywords :
Hilbert transforms; OFDM modulation; mean square error methods; modems; synchronisation; Hilbert transform; MIL-STD-188-110B; MSE; OFDM based HF modem; analog quadrature demodulation module; analog quadrature modulation module; frequency offset estimation method; frequency synchronization; orthogonal frequency division multiplexing; parallel HF modem; parameter design; AWGN; Frequency division multiplexing; Frequency estimation; Frequency response; Frequency shift keying; Frequency synchronization; Hafnium; Modems; Narrowband; OFDM modulation;
Conference_Titel :
Circuits and Systems for Communications, 2008. ICCSC 2008. 4th IEEE International Conference on
Conference_Location :
Shanghai
Print_ISBN :
978-1-4244-1707-0
Electronic_ISBN :
978-1-4244-1708-7
DOI :
10.1109/ICCSC.2008.96
