TABLE OF CONTENTS In this chapter we consider the design of a wireless receiver. We start by considering the phenomena that impact the performance of the receiver, such as noise, which is considered in section 6.2, and intermodulation distortion, which is considered in section 6.3. Then we present some commonly used receiver architectures, such as the superheterodyne receiver in section 6.4, the homodyne receiver in section 6.5, and software radio, which is a fully digital and programmable transceiver in section 6.6.
The performance of a wireless receiver is best described in terms of its figures of merit, these include:
Noise figure. This is the ratio between the signal-to-noise ratio at the input of the receiver to that at the output of the receiver. The noise figure can also be described in terms of the noise temperature.
Linear dynamic range. This is the input signal range between the receiver s threshold, where the signal-to-noise ratio is 0 dB, to the linearity limit, where the gain of the receiver drops by 1 dB from its small signal value.
Spurious-free dynamic range. This is the input signal range between the receiver s threshold, and input signal level where second or third-order non-linear effects equal the threshold level. The spur-free dynamic range is usually less than the linear dynamic range.
Any receiver adds noise to the received signal. The amount of noised added by the receiver is determined by a receiver parameter known as the noise figure ...
