C2000 is a communication system based on the Terrestrial Trunked Radio (TETRA) protocol and is used in the Netherlands by emergency services. We investigated the resilience of the voice component of C2000 against intelligent intentional electromagnetic interference (IEMI). Low power signals interfering with the system’s higher protocols have the advantage of staying covert. The analysis shows t...

In this paper, we consider the optimization of the performance of QPSK and 16-QAM coded orthogonal frequency division multiplexing (COFDM) signals over the non-linear and mobile satellite channel. A high power amplifier and Rician flat fading channel produces non-linear and linear distortions; an adaptive predistortion technique combined with turbo codes will reduce both types of distortion. Th...

The recent emergence of efficient O-band amplification technologies has enabled the consideration transmission beyond short reach. Despite being a low chromatic dispersion (CD) window, impact CD will become increasingly significant when extending reach direct-detection (DD) systems. In this work, we first numerically investigate 3-dB bandwidth single-mode fibers (SMF) and CD-restricted in inten...

Quadrature Phase Shift Keying (QPSK) and Offset Quadrature Phase Shift Keying (OQPSK) are two wellaccepted modulation techniques used in Code Division Multiple Access (CDMA) system. The Pulse-Shaping Filters play an important role in digital transmission. The type of Pulse-Shaping Filter used, and its behavior would influence the performance of the communication system. This in turn, would have...

Mobile communication system uses Quadrature Phase Shift Keying (QPSK) as one of the efficient digital modulation techniques. Pulse-shaping technique plays an important role in digital transmission. Root-Raised Cosine (RRC) and Raised Cosine (RC) filters are two important pulse-shaping filters used in mobile communication system. In this paper we have presented the study of some useful parameter...

We theoretically analyze the phase noise transfer issue between the pump and the wavelength-converted idler for a nondegenerate four-wave mixing (FWM) scheme, as well as study the vector theory in nonlinear semiconductor optical amplifiers (SOAs), in order to design a polarization-insensitive wavelength conversion system employing dual co-polarized pumps. A tunable sampled grating distributed B...

In this paper, introduced below are the concepts of digital modulation used in many communication systems today. Techniques described include quadrature phase shift keying (QPSK) and quadrature amplitude modulation (QAM) and how these techniques can be used to increase the capacity and speed of a wireless network. These modulation techniques are the basis of communications for systems like cabl...

This article discusses QPSK, OQPSK, π/4 DQPSK and the trade offs involved. Later we discuss various CPM schemes and their relative bandwidth efficiencies. Probability of Bit error is discussed for various schemes assuming an AWGN channel. A model is devised, ignoring any changes in phase, to determine the error probabilities for flat fading channels. The article ends with a brief discussion of ...