The performance of digital mobile radio systems when transmitting at over several tens of kbit/s severely degrades with the onset of fast fading multipath propagation. This paper proposes a dual-mode equalization (DME) method to overcome the degradation and experimentally verifies the effectiveness of the method.
The new method uses decision feedback equalizers (DFEs) in two modes simultaneously, a normal mode, and a time-reversal mode, and selects the best equalization result.
The time-reversal equalization mode improves the characteristics of equalization and adaptation in the non-minimum phase condition. It converts the nonminimum phase to the minimum phase condition by the time-reversal operation.
Principles of dual-mode equalization, an algorithm for mode output selection, and timing problems are discussed in detail. Experiments demonstrate average BER performance in two-path and typical multipath environments. The proposed dual-mode equalization technique improves average BER performance by 2 dB Eb/N0.
[1]
S. Qureshi,et al.
Adaptive equalization
,
1982,
Proceedings of the IEEE.
[2]
Renato D'Avella,et al.
An adaptive MLSE receiver for TDMA digital mobile radio
,
1989,
IEEE J. Sel. Areas Commun..
[3]
Sirikiat Lek Ariyavisitakul,et al.
A Novel Anti-Multipath Modulation Technique DSK
,
1987,
IEEE Trans. Commun..
[4]
H. Suzuki.
Performance of a new adaptive diversity-equalisation for digital mobile radio
,
1990
.
[5]
S. Ariyavisitakul.
Equalization of a hard-limited slowly-fading multipath signal using a phase equalizer with a time-reversal structure
,
1990,
40th IEEE Conference on Vehicular Technology.