POTENTIAL DEVICES AND METHODS USEFUL IN RADIOS

This section describes some methods and devices that may be useful in implementing radio 

receivers where digitization occurs at the RF or IF. These methods and devices probably will be 

considered in the design of future radio receivers as the digitization of received signals 

progresses toward the receive antenna. Various quantization techniques are discussed since the 

authors believe that this area has great potential for use in radio receiver applications. Nonlinear 

compression devices are discussed, including log amplifiers and automatic gain control devices. 

Postdigitization algorithms for improving the SFDR provide extended dynamic range capability 

for presently available ADCs. Sampling downconverter technology is introduced. This 

technology is based on the theory of bandpass sampling and may be coupled with ADC 

technology to provide improved ADC performance for bandpass sampling applications. Finally, 

specialized integrated circuits for digital signal-processing tasks required in radio receiver 

applications are mentioned. An example of this type of technology, the Harris HSP50016 digital 

downconverter, is presented.