3Analog Device Inc. AD9244 data sheet[EB/OL]. http:∥www.analog.com,2002-06-01/2002-09-12.
4Elwan H, Ismail M. Digitally programmable decibel-linear CMOS VGA for low-power mixed-signal applications[J]. IEEE Trans on Circuits and Systems-Ⅱ: Analog and Digital Signal Processing, 2000,47(5):388-390.
5Newman J. A new 45 dB 500 MHz variable gain amplifier simplifies adaptive receiver designs[EB/OL]. Analog Device Inc. http:∥www.analog.com,2001-12-01/2002-05-10.
6Analog Device Inc. AD8369 data sheet[EB/OL]. http:∥www.analog.com,2002-06-12/2002-09-10.
7GORIN J.All-digital IF gives new spectrum analyzers FFT speed and swept dynamic range[DB/OL].http://www.agilent.com,2000.
8GORIN J M,SHEPPARD R D.Auto ranging apparatus and method for improved dynamic ranging in analog to digital converters[P].United States Patent 5844512,1997.
