Signal Processing for Communication Systems
Key focus: Simulate bit error rate performance of Binary Phase Shift Keying (BPSK) modulation over AWGN channel using complex baseband equivalent model in Python & Matlab. This post contains interactive python code which you can execute in the browser itself. Why complex baseband equivalent model The passband model and equivalent baseband model are fundamental models … Read more
The phase transition properties of the different variants of QPSK schemes and MSK, are easily investigated using constellation diagram. Let’s demonstrate how to plot the signal space constellations, for the various modulations used in the transmitter. Typically, in practical applications, the baseband modulated waveforms are passed through a pulse shaping filter for combating the phenomenon … Read more
What’s the need for GMSK Minimum shift keying (MSK) is a special case of binary CPFSK with modulation index $latex h=0.5$. It has features such as constant envelope, compact spectrum and good error rate performance. The fundamental problem with MSK is that the spectrum is not compact enough to satisfy the stringent requirements with respect … Read more
In coherent detection, the receiver derives its demodulation frequency and phase references using a carrier synchronization loop. Such synchronization circuits may introduce phase ambiguity $latex \phi = \hat{\theta}-\theta $ 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 $latex … Read more
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
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
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
