Radio equipment using image signals for compensating transmission signals

Abstract

Disclosed is radio equipment for transmission and reception of Frequency Division Duplex mode signals and transmission signal characteristic compensation utilizing small-scaled circuit construction. A receiver converts Radio Frequency band signals from an antenna sharer to an Intermediate Frequency (IF) via a mixer and into digital signals utilizing an Analog-to Digital Converter. Reception signals and image signals of transmission signals, both having an IF A are contained in the converted signals, are converted into reception signals having an IF B and image signals having an IF C, respectively, which both have positive and negative carrier frequencies symmetrical to a zero frequency direct current component and are represented as a complex number. A transmitter converts the IF C into a baseband of image signals, and compensates signal characteristics relative to complex baseband signals of quantized transmission signals at a characteristic compensator using converted signals as reference signals.