Category: Analog Professional

Posts that would interest electrical engineers proficient in analog circuit design.

Challenges of Polar Modulation

I’ve heard for the last 10 years or so that polar modulation will give spectrally-efficient modulation formats (OFDM, CDMA, etc.) the PA efficiency that they so lack nowadays. I agree: polar modulation will give a boost in efficiency—when several problems are solved. Here are the challenges that plague polar modulation

Calibrated level-shifting circuit

In response to:Watch Full Movie Online Streaming Online and Download Hi all, I came across a dc biasing problem of a homodyne receiver. The output of the direct conversion mixer is connected to a VGA. The first stage of VGA and the output of mixer have different DC biasing values. I know common source or […]

A simple sigma-delta loop

In my post on Quantization, I noted that quantization noise degrades the performance of analog-to-digital converters (ADC’s). One very effective method of reducing quantization noise over narrow (but increasingly wider) bands is the Sigma-Delta technique. Consider the block diagram shown below: This loop attempts to subtract the error induced by the embedded ADC (called the […]