Baseband Processing in 3G UMTS Radio Base Stations

• This report presents a study of functionality, service dataflows, computation characteristics and processing parameters for baseband processing in radio base stations. The study has been performed with the objective to develop a programming model that is natural and efficient to use for baseband programming and which can be efficiently compiled to parallel computing structures. In order to achieve this objective it is necessary to analyse and understand the logical architecture of the application in order to be able to define processing characteristics and thereby requirements on languages as well as on physical system architectures. Moreover, to be able to test and verify programming and mapping of functions it is necessary to have realistic but still manageable test cases. The study is focused on the third generation partnership project (3GPP) standard specifications for 3G radio base stations. The specifications cover the complete 3G network-architecture and are quite extensive and complex. To make experiments manageable, it is necessary to abstract system functionality that is not directly relevant for the RBS baseband processing. Moreover, the standard specifications only describe the required processing functionality on an abstract logical level. In this report, the functionality of the baseband functions is explained and also described using illustrations of dataflows and abstract mapping of two 3G service cases. The results of the study constitute a comprehensive description of the processing flow and the mapping of user data channels in 3G radio base stations – spanning data and control input from layer 2 to physical channel output from layer 1. Data dependencies between functions are illustrated with figures and it is concluded that these dependencies are of producer/consumer type. It is discussed how different functions can be mapped in MIMD and SIMD fashion with regard to the data dependencies, the data stream lengths and the control operations required to handle bit stream processing on word-length processor architectures.

Subject headings

NATURVETENSKAP  -- Data- och informationsvetenskap -- Datavetenskap (hsv//swe)

NATURAL SCIENCES  -- Computer and Information Sciences -- Computer Sciences (hsv//eng)

Keyword

Baseband processing

Radio base stations

TECHNOLOGY

TEKNIKVETENSKAP

Publication and Content Type

vet (subject category)

rap (subject category)