In response to: How can I deal with 3rd HD in a 2nd SigmaDelta Modulator It’s possible that the OTA is limiting you. Doing a matlab model of the sigma-delta and running it should tell you whether it is a circuit problem or a system-level problem. My hunch is that it’s a system-level problem: the […]
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
I wrote a set of scripts to make Cadence IC tools & Subversion work together. This requires subversion 1.4 or higher. Red Hat Enterprise Linux 4 by default ships with 1.3. See also Pictorial Introduction to Using Cadence/Subversion for detailed tutorial on usage. This post is mostly about the guts of the scripts. Note: this […]
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 […]
There are three main differences you’ll see from digital TV: More Channels All or Nothing Reception Deeper Coverage
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 […]
I intend to explain a very powerful concept in data conversion: the Sigma-Delta loop. Before I do so, I will describe quantization noise (which sigma delta loops attempt to alleviate). Quantization noise occurs during the analog-to-digital conversion (ADC) process. Since an analog signal can attain any value, it has infinite precision. This infinite precision excludes […]