A Wideband Digital RF Receiver Front-End Employing a New Discrete-Time Filter for m-WiMAX Heesong Seo, Student Member , IEEE, Inyoung Choi , Student Member , IEEE

Abstract

A wideband digital RF receiver front-end employing a discrete-time (DT) filter is presented for application to m-WiMAX (WiBro). By employing a sampling mixer and a DT filter, the re- ceiver operates in the charge domain. In addition to the flexibility of the DT filter, the new non-decimation finite impulse response (NDF) filter can be cascaded to a conventional finite impulse re- sponse (FIR) filter without the decimation effect. Thus, we can easily increase the order of the function-type filtering re- sponse and the signal processing bandwidth. The FIR filter is also modified to reduce the noise and the number of required clock signal. Because of the new filter con figuration, clock signals can be shared by the FIR filter and NDF filter and the clock generator circuit can be simpli fied. The designed receiver front-end is imple- mented using an IBM 0.13- m RF CMOS process. The fabricated chip satisfies the m-WiMAX speci fication of an 8.75 MHz channel bandwidth and the total system current dissipation is 26.63 mA from a 1.5-V supply voltage.