4LAUGHTON M A, WARNED E. Electrical engineering, s reference book [M]. United States: Elsevier Science Ltd, 2002: 22-259.
5CHING-HSIANG T, HSIU-FENG C. Digital quadrature demod- ulation of multiple RF signals [J]. Workshop on Signal Processing Advances in Wireless Communications, 2005(06): 37-41.
6SIMEU E, MIR S. Envelope detection based transition time supervision for online testing of RF MEMS switches [J]. IEEE International On-Line Testing Symposium, 2007, 07 (13) : 237-243.