by George, Kiranraj

Abstract (Summary)
The lack of a priori knowledge about the waveform of interest, the multitudes of signals the receiver might receive, and the noise energy that occupies the same portion of the frequency spectrum as the signal makes the design of a modern wideband receiver very challenging. Especially, the receiver must be able to detect a weak signal in the presence of a strong one, which requires a high two-signal instantaneous dynamic range (IDR). To fulfill this requirement, the receiver must detect genuine weak signals and avoid the detection of strong signals’ sidelobes and noise and spurs generated from the receiver system. The other major trend in modern receiver signals is the shift towards wider bandwidths. Analog wideband receiver designs can provide accommodation of the technology-stressing bandwidths, but come up to a cost of reduced flexibility. Digital approaches, alternatively, provide flexibility in receiver signal processing, but they are limited by analog-to-digital converter resolution and power consumption. In this dissertation, design and performance evaluation of a 1-GHz signal bandwidth digital receiver, which uses a Kaiser Window function and a compensation technique, is presented. The Kaiser Window reduces the spectral leakage by eliminating the discontinuities at the time window edges and the compensation uncovers the weak signal for extension of the two-signal IDR of the receiver. An exhaustive study of configuration of ADC, FFT, window function, and compensation for a maximum achievable two-signal IDR of the receiver is conducted. It is shown that using a 4-bit ADC and a 256-point FFT of 12-point kernel function, a maximum two-signal IDR of 9 dB is obtained. The IDR is extended to 14 dB by using the Kaiser window and to 18 dB by using the compensation. Furthermore, using a 4-bit ADC and an ideal 256-point FFT, a maximum two-signal IDR of 11 dB is obtained. The IDR is extended to 17 dB by using the Kaiser window and to 22 dB by using the compensation. A combination of both Kaiser window and compensation techniques extends the two-signal IDR of the receiver to 24 dB by using a 12-point kernel function FFT and 29 dB by using an ideal FFT. A novel hardware implementation of the Kaiser window, the compensation technique, and the receiver design is presented.
Bibliographical Information:


School:Wright State University

School Location:USA - Ohio

Source Type:Master's Thesis

Keywords:wideband digital receiver two signal instantaneous dynamic range processing kaiser window function compensation technique spectral leakage monobit high precision estimation on a chip multiple dete


Date of Publication:01/01/2007

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