Flexible multi-standard multi-channel system architecture for Software Defined Radio receiver

Abstract

New telematic services require high data rates for additional information, which can no longer be provided on low bitrate broadcast channels like RDS (Radio Data System) over analog FM. A solution are digital broadcast standards, such as DAB (Digital Audio Broadcast), DRM (Digital Radio Mondiale) or IBOC (In-Band-on-Channel, e.g. HDRadio), which offer about 100x higher bitrates and enable modern and sophisticated traffic management applications. To overcome the hassle of building and integrating a new hardware device for each new tuner and each transmission system, a Software Defined Radio (SDR)-based approach helps implementing several standards in a single system and therefore reduce hardware resources and cost by sharing common functions between different decoder. In this paper, a flexible SDR broadcast receiver system architecture is discussed, which can decode audio and data streams of multiple radio stations and multiple broadcast standards simultaneously. Common modules are time-shared between different channels instead of integrating each tuner as separate path for each concurrently decoded station. A single instance of a processing block is sufficient to handle multiple channels with the help of FIFO memory buffers, provided it can be efficiently used in a time shared manner. Performance requirements and limits for an telematic broadcast SDR receiver are discussed in this paper. A real-time capable wideband FM/RDS receiver and a DAB receiver, which has been realized on a Xilinx Virtex-4 FPGA, will serve as example for discussing required resources and time sharing of hardware broadcast receiver.