Differentially encoded BPSK: coherent detection

In coherent detection, the receiver derives its demodulation frequency and phase references using a carrier synchronization loop. Such synchronization circuits may introduce phase ambiguity in the detected phase, which could lead to erroneous decisions in the demodulated bits. For example, Costas loop exhibits phase ambiguity of integral multiples of radians at the lock-in points. As … Read more

Complex Baseband Equivalent Models

Key focus: Complex Baseband Equivalent Models are behavioral models that simplify the simulation, saves computation memory requirements and run time. This article is part of the book Digital Modulations using Matlab : Build Simulation Models from Scratch Introduction The passband model and equivalent baseband model are fundamental models for simulating a communication system. In the … Read more

Passband Simulation Models – Introduction

For a given modulation technique, there are two ways to implement the simulation model: passband model and equivalent baseband model. The passband model is also called waveform level simulation model. The waveform level simulation techniques, described in this chapter, are used to represent the physical interactions of the transmitted signal with the channel. In the waveform … Read more

QPSK – Quadrature Phase Shift Keying

Quadrature Phase Shift Keying (QPSK) is a form of phase modulation technique, in which two information bits (combined as one symbol) are modulated at once, selecting one of the four possible carrier phase shift states. The QPSK signal within a symbol duration \(T_{sym}\) is defined as where the signal phase is given by Therefore, the … Read more

Performance comparison of Digital Modulation techniques

Key focus: Compare Performance and spectral efficiency of bandwidth-efficient digital modulation techniques (BPSK,QPSK and QAM) on their theoretical BER over AWGN. More detailed analysis of Shannon’s theorem and Channel capacity is available in the following book● Wireless Communication Systems in Matlab (second edition), ISBN: 979-8648350779 available in ebook (PDF) format and Paperback (hardcopy) format. Simulation of various … Read more

BPSK – Binary Phase Shift Keying

Key focus: BPSK, Binary Phase Shift Keying, bpsk modulation, bpsk demodulation, BPSK matlab, BPSK python implementation, BPSK constellation BPSK – introduction BPSK stands for Binary Phase Shift Keying. It is a type of modulation used in digital communication systems to transmit binary data over a communication channel. In BPSK, the carrier signal is modulated by … Read more