Design and ASIC performance analysis of a reconfigurable digital filter for a UMTS application

A reconfigurable digital root raised cosine (RRC) filter for a UMTS terrestrial radio access (UTRA) mobile terminal receiver is described and analysed. The filter monitors in-band and out-of-band received signal powers and calculates the appropriate filter length that meets the bit-energy to interference ratio (Eb/No). This design is advantageous, as only minimum battery power is used resulting in power consumption savings compared to fixed filter length digital filters. A 70% average power reduction is available for the UTRA - time division duplex (TDD) system.