In this contribution we point out that the nondecision-aided (NDA) carrier synchronizer, maximizing the low E s / N o limit of the likelihood function averaged over a general 2r/N-rotationally symmetric signal constellation, reduces to the familiar timing-aided Nth power synchronizer; this extends a result from [6] where only M-PSK constellations have been considered. Whereas in the case of M-P...

This paper presents a 5 bit charge-redistribution phase domain ADC (PhADC) implemented in 0.18 μm CMOS technology for low power FSK/PSK demodulation. An IQ-assisted conversion algorithm is proposed to avoid the need for an accurate linear combination of in-phase (I) and quadrature (Q) signals with various scaling factors in a conventional zerocrossing algorithm, thus eliminating the power consu...

| We derive generalized analytical constructions of linear realeld (LRF) codes for transmissions over wireless fading channels. We show cases where LRF-coded QAM, PAM, or PSK constellations can achieve maximum diversity and large coding gains. We construct analytically LRF codes, which not only yield larger coding gains than existing designs in most cases, but also produce LRF-coded QAM or PAM ...

A trellis-coded modulation scheme, using a coded 2-FSK/2"-PSK modulation format instead of a conventional coded 2"+'-PSK format for m-bitslsymbol data transmission, is considered. Previous work [I, 21 on coded 2FSK/2"-PSK modulation techniques choose two transmission frequencies equally often. In contrast, our method selects the signal points in such a manner that each of the signal dimensions ...

Space-time convolutional codes, that provide maximum diversity and coding gain, are produced for cases with PSK modulation and various numbers of states and antennas. The codes are found using a new approach introduced recently in a companion paper. The new approach provides an eecient method that allows a search for optimum codes for many practical problems. The new approach also provides a si...

A precoder is designed for orthogonal space-time block codes (OSTBCs) for arbitrarily correlated Ricean multiple-input multiple-output (MIMO) channels. Unlike previous works, our precoder is the first to be designed to minimize the exact symbol error rate (SER) as function of both a) the joint transmit-receive channel correlation coefficients, and b) the MIMO Rice component, which are fed back ...

A very important problem in fade countermeasure systems is the need to detect signal quality quickly and accurately. In fact, the countermeasure has to be initiated before the signal degradation effect on the bit error rate is detected by the user. This paper presents an overview of different methods to evaluate signal quality, which are based on the availability of soft quantized levels of PSK...

This paper deals with modulation classification, First, a state of the art is given which is separated into two classes: the pattern recognition approach and the Maximum Likelihood (ML) approach. Then we propose a new classifier called the General Maximum Likelihood Classilier (GMLC) based on an approximation of the likelihood function. We derive equations of this classifier in the case of line...

Absfracr-Conventional techniques attempting to compensate for the influence of linear and nonlinear distortion in digital satellite channels include optimization of channel filtering. With conventional linear filtering it has been experienced that there is still room for considerable improvement, so that i t appears reasonable to investigate some forms of nonlinear filtering in an attempt to co...