An efficient carrier recovery scheme for high-bit-rate W-band satellite communication systems

Abstract

Abstract-Recent efforts in satellite communication research considered the exploitation of higher frequency bands as a valuable alternative to conventional spectrum portions. An example of this can be provided by the Wband (70-110GHz). Recently, a scientific experiment carried on by the Italian Space Agency (ASI), namely the DAVID-DCE experiment, was aimed at exploring the technical feasibility of the exploitation of the W-band for broadband networking applications. Some preliminary results of DAVID research activities pointed out that phase noise and high Doppler-shift can severely compromise the efficiency of the modulation system, particularly for what concerns the aspects related to the carrier recovery. This problem becomes very critical when the use of spectrally efficient M-ary modulations is considered in order to profitably exploit the large amount of bandwidth available in the W-band. In this work 12 , a novel carrier recovery algorithm has been proposed for a 16-QAM modulation and tested, considering the presence of phase noise and other kinds of non-ideal behaviors of the communication devices typical of W-band satellite transmission. Simulation results demonstrated the effectiveness the proposed solution for carrier recovery and pointed out the achievable spectral efficiency of the transmission system, considering some constraints about transmitted power, data BER and receiver bandwidth.

Use of Trellis-Coded Modulation for Gigabit/sec Transmissions over W-Band Satellite Links

“…In particular, the development of a robust carrier recovery scheme, able at working in presence of phase noise and signal distortions has been proposed and discussed. Experimental results shown in [9] evidenced a not negligible influence of phase-noise on BER performances. In particular, a disturbing channel BER increase (up to one order of magnitude) can be observed for an increase of the phase-noise standard deviation (critical values >10°).…”

“…This involves the necessity of introducing robust and, therefore, redundant channel coding that can improve data BER performances, but, on the other hand, consistently reduces the net payload rate available. It must be said that results shown in [5] and [9] do not consider anomalous propagation phenomena. Truly, the strong uncertainty about physical channel characterization may represent a potential "black hole" in the usage of W-band in satellite connections.…”

“…Finally, a frequency divider returns the recovered carrier at the correct IF. Such a scheme has been proven in critical conditions of signal distortion and phase noise and exhibits a greatly improved robustness with respect to state-of-theart schemes [9].…”

“…For this reason, we have to employ more complicated carrier recovery circuits, able to work in presence of high Doppler-shifts to be tracked and high levels of phase noise conveyed by the high-frequency oscillators present in the chain. As far as carrier recovery aspects are concerned, we refer here to the robust scheme proposed by Sacchi, Musso, et al in [9] and drawn in Fig. 9.…”

“…Also Internet browsing services supported by TCP/IP protocol are characterized by tight requirements in terms of spectral efficiency [8] in order to maximize system throughput and reduce latency times. Preliminary results about the employment of a 16-QAM modulation with Reed-Solomon channel coding in W-band LEO satellite connections have been shown in [9]. In particular, the development of a robust carrier recovery scheme, able at working in presence of phase noise and signal distortions has been proposed and discussed.…”