A Real-time Input Data Buffering Scheme Based on Time Synchronization for a T-DMB Software Baseband Receiver

Abstract

To decode a broadcasting signal such as a T-DMB signal using a software baseband receiver running on a digital signal processor (DSP), real-time input data buffering is important. A time offset of each received frame, which is caused by a difference in the sampling frequency between the transmitter and the receiver, makes input buffer management difficult, eventually resulting in the performance deterioration of the receiver. This work proposes an input data buffering scheme based on a ring buffer for a T-DMB software baseband receiver running on a DSP. The time offset of each received frame is estimated by a time synchronization block using a phase reference symbol and is used by a buffer controller to control the ring buffer so that the receiver on the DSP always reads valid data for data decoding. The validity of the proposed scheme is confirmed by showing that the ring buffer never goes into an overflow state when buffering the input data with a time-varying time offset. Thus, the specified receiver performance is guaranteed over time.