Book

From my book Wireless Communications – From the Ground Up

Moving Average Filter

Coefficients of a moving average filter in time domain

The most commonly used filter in DSP applications is a moving average filter. In today’s world with extremely fast clock speeds of the microprocessors, it seems strange that an application would require simple operations. But that is exactly the case…
Read more

Basics of Synchronization

Known training sequence (a preamble) is prepended, or training can also be inserted periodically within the message

In every digital communication system, the Tx has the easier role of signal generation while the Rx has the tougher job of figuring out the intended message. Just like solving a puzzle told by someone. Estimating and compensating for the…
Read more

Quadrature Amplitude Modulation (QAM)

A general QAM detector with respective waveforms at each block

We discussed earlier that Pulse Amplitude Modulation (PAM) transmits information through amplitude scaling of the pulse according to the symbol value. To understand QAM, we have to differentiate between baseband and passband signals. A baseband signal has a spectral magnitude…
Read more