MULTI-BAND TRANSCEIVER UTILIZING DIRECT CONVERSION RECEIVER AND DIRECT CONVERSION RECEIVER

摘要

A multi-band transceiver having a receiver portion and a transmitter portion, wherein the receiver portion includes a direction conversion system for directly downconverting a signal to baseband frequencies. The direct conversion receiver system includes a frequency translator having first and second inputs and an output. The first frequency is preferably an nth order subharmonic of the second frequency, wherein n is an integer greater than 1. A low pass filter is integral with or inherent to the first input and a high pass filter is integral with or inherent to the second input. A direct conversion receiver system is also provided in which a first input signal at a first frequency is applied to a first input port of a multiplier, and a second input signal at a second frequency equal to about 1/n times the first frequency wherein n is an integer, is applied to a second input port of the multiplier. A first filter coupled to the first input port is configured to substantially filter out any leakage at the second frequency which may be present. A second filter is configured to substantially filter out any leakage at the first frequency which may be present. The multiplier is configured to produce a signal at an output port thereof which is derived from the product of the first and second signals.