A method to improve the reliability of data transmission between two terminals without using multiple antennas is cooperative communication, where spatial diversity is introduced by the presence of a relay terminal. The Quantize and Forward (QF) protocol is suitable to implement in resource constraint relays, because of its low complexity. In prior studies of the QF protocol, all channel parame...

In this paper we study serial turbo interconnections of Abelian group codes to be used on symmetric channels. Particular attention is devoted to AWGN channel with input restricted to m-PSK constellation with corresponding group structure Zm. We establish the exact asymptotic decay of the average symbol and word error probabilities when the interleaver length goes to infinity (interleaver gain)....

This lecture first introduces the standard representation of complex baseband signal of digital modulated signal and its power spectral density (PSD). Then it shows how the PSD of bandpass signals can always be obtained by its complex baseband envolope. Finally, two important modulation schemes OFDM and PSK are introduced and the spectral characteristics of these two modulated signals are discu...

In this work we present a simple, but effective method of enhancing and exploiting diversity from multiple packet transmissions in systems that employ nonbinary linear modulations such as PSK and QAM. This diversity improvement results from redesigning the symbol mapping for each packet transmission. Using a general framework for evaluating the upper bound of bit error rate (BER) with multiple ...

Linear (translation), hard-limited, and demod/remod types of satellite repeaters are considered in this paper. Both uncoded and coded multiple phase shift keyed (MPSK) signals are assumed to be transmitted through these repeaters. Relative performances of these repeaters in the presence of uplink and downlink noises are then compared quantitively. Probabilities of bit errors and the computation...

We consider the problem of fingerprinting text by sets of symbols. Specifically, if S is a string, of length n, over a finite, ordered alphabet Σ , and S′ is a substring of S, then the fingerprint of S′ is the subset φ of Σ of precisely the symbols appearing in S′. In this paper we show efficient methods of answering various queries on fingerprint statistics. Our preprocessing is done in time O...

To detect spatially-modulated signals, a receiver needs the channel state information (CSI) about each transmit-receive antenna pair. Although the CSI (or channel response information) is never perfect and varies in time, most studies on spatial modulation (SM) systems assume perfectly known CSI and time-invariant channel. The spatial correlations among multiple spatial subchannels, which have ...

A length n group code over a group G is a subgroup of G under component-wise group operation. Group codes over dihedral groups DM , with 2M elements, that are two-level constructible using a binary code and a code over ZM residue class integer ring modulo M , as component codes are studied for arbitrary M . A set of necessary and sufficient conditions on the component codes for the two-level co...

We study the synergy between coded modulation and antenna-diversity reception on channels affected by slow Rician fading. Specifically, we assess the impact of channel-state information (CSI) on error probability. We show that with a good coding and constant envelope modulations (like PSK) scheme the loss in performance when CSI is not available is moderate (around 1.5 dB). Moreover, as the div...