一种高性能直接射频调制多功能正交调制器的研制

The Research of A High-performance Direct RF-modulation and Multi-functional Quadrature Modulator

在现代无线通信系统中 ,对发射信号进行直接射频调制已成为射频无线电的发展趋势。采用ADI公司的AD8345作为工作频段为 2 5 0～ 10 0 0MHz的正交调制芯片 ,用ADI公司的AD8132和AD976 1提供差分输入 ,并采用MAXIM公司的MAX2 6 2 0提供 90 0MHz的射频信号 ,可以设计出一款在CDMA/GSM系统中 90 0MHz频带内作为直接射频调制的调制器或在数字电视和CATV中作为正交幅度 (或相移 )键控的调制器 ,以产生QPSK和各种QAM格式的信号。

In modern wireless communication system, the direct RF-modulation for transmitting signal is a new developing trend of RF radio. Using the AD8345 by ADI which is a quadrature modulator operationg from 250～1 000 MHz, the AD8132 by ADI and AD9761 which can supply differential drive signal, as well as the MAX2620 by MAXIM which supply the RF signal at 900 MHz, we can develop a new direct RF-modulation modulator for CDMA/GSM system at 900MHz or QASK(QPSK) modulator for digital TV and CATV, so as to produce QPSK and various QAM formats signals.