Service Adaptable 3G Turbo Decoder for Indoor/Low Range Outdoor Environment
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Abstract
For the well-known 3G mobile communications standard UMTS, four different service classes have been specified. Considering two turbo decoding algorithms, like SOVA and log-MAP, it would be desirable to use an efficient turbo decoder. In this paper this decoder is shown to adapt dynamically to different service scenarios, considering parameters like performance and complexity for indoor/low range outdoor operating en-vironment. The scenarios show that for streaming service class real-time class applications the proposed de-coding algorithm depends on data rate; for the majority of scenarios SOVA is proposed, whereas log-MAP is optimal for increased data rates and medium-sized frames. On the other hand, conversational service class real-time applications cannot be established. For the majority of non real-time applications (interactive and background service classes) either algorithm can be used, while log-MAP is proposed for medium data rates and frame lengths.
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