Synchronization in M-PSK modems

Abstract

In many applications, it is economical for a single modem to receive multiple modulation formats. In particular, the use of BPSK and QPSK has become a defacto standard in many military and NASA systems. However, there is significant interest in employing 8PSK and 16PSK modulation in these same systems today in order to conserve bandwidth. This paper addresses a technique for achieving carrier synchronization for all four of these PSK schemes in a single modem. This is accomplished by using quadrature channel carrier recovery processing and a version of the MAP phase detector algorithm. A model for the simulation of this tracking process is derived and results are presented to c o n f i i its functionality.

A Methodical Approach to Hybrid PLL Design for High-Speed Wireless Communications

“…The only modulation-dependant variables are (a) the phase detector and its gain K d , and (b) the squaring loss (which influences [9 Sec. 11 [17], [18], [19], [2 Chap. 5,6] .…”

Phase jitter in MPSK carrier tracking loops: analytical, simulation and laboratory results

“…This characteristic can be expressed in terms of the transmitted modulation angle, data estimates, and phase error as [4] (7)…”

A robust phase detection structure for M-PSK: theoretical derivations, simulation results, and system identification analysis

“…4 and Fig. 7 (see [10]- [12]). Maintaining a constant loop bandwidth is the practice adopted in most synchronization texts (e.g.…”

“…6-2, [10]- [12]). NDA detectors, while not susceptible to such a phenomenon, are nonetheless seldom used for higher order modulations.…”

“…The M th -order nonlinearity detector ( [3], [6], [13]) and the multiphase NDA Costas loop ( [3], [5], [13]) are examples of NDA phase detection. Examples of DD detectors can be found in [3], [6], [10]- [13], and [16].…”