This summary presents the further analysis primarily corresponding to power spectral density (psd) of OFDM and PSK modulations. Here is the continuation of analysis of OFDM (chapter 2), description of PSK properties (chapter 3) and detailed derivation of PSK psd (chapter 4). The summary is concluded with compression of PSK bandwidth efficiency depending on the alphabet size and with introductio...

In this paper we present Walsh-quadrature phase-shift keying (Walsh-QPSK) pseudonoise (PN) modulation schemes for both coherent and noncoherent direct-sequence code-division multiple-access (DS-CDMA) systems, wherein the PN spreading sequences for in-phase and quadrature data in a conventional QPSK PN modulation scheme are coded by Walsh sequences indexed by a special rule to reduce the envelop...

A simple, low cost radio frequency (RF) power and spectrally efficient integrated transceiver/modem architecture employing Feher’s patented Quadrature Phase Shift Keying (FQPSK) is described. The FQPSK signals presented in this paper are obtained by using additional post low-pass filters in the FQPSK architecture. This implementation significantly improves the spectral efficiency of the worldwi...

Orthogonal Frequency Division Multiplexing (OFDM) is a key technique for achieving high data rates and spectral efficiency requirements for wireless communication systems. This paper presents a modeling and simulation of OFDM based on WLAN standard (IEEE 802.11a). Performance of OFDM is evaluated for different modulation schemes such as PSK, QAM, DQPSK, and OQPSK. The performance of OFDM is com...

This paper considers the bit error probability analysis of Direct-Sequence Code-Division Multiple Access (DS-CDMA) system. A statistical characterization of the decision variable at transmitter and receiver is obtained. System is simulated with OQPSK modulation scheme which when compared with conventional Binary Phase Shift Keying (BPSK) gives improved performance in terms of Probability of Err...