Ofdm Test System Based On Spectrum Polymerization Research And Implementation Of Adaptive Transmission Technique

Nowadays, with the increasingly tense and shortage of spectrum resources,spectrum aggregation technology, as a key technology of next generation mobilecommunication system, has got widespread attention, due to its advantage ofaggregating the scattered spectrum resources to expand the system bandwidth.Orthogonal frequency division multiplexing (Orthogonal Frequency DivisionMultiplexing, OFDM) technology has become a key technology in next generationmobile communication systems, because of its advantage of improve the spectralefficiency besides improving the system data rate. In addition, due to the timevariability of the radio channel, how to maximize the use of radio channel resourcesbecomes important. Self-adaptive transmission technology improves systemperformance and the use of wireless channel resourse by adaptively adjusting systemtransmission parameters under dynamic wireless channel conditions.This thesis mianly studies the adaptive transmission technology based on thespectrum aggregation OFDM system and the realization.Firstly, this thesis studies the spectrum aggregation OFDM system adaptivetransmission technology including adaptive modulation and coding techniques andadaptive spectrum aggregation techniques, and investigates the comparison of twoclassical adaptive modulation and coding algorithms and a new adaptive modulationand coding algorithm-the supervised learning adaptive modulation coding algorithmbased on the sort SNR (Singnal Noise Ratio). After verified the effectiveness andsuperiority of the new algorithm in the single-antenna OFDM system, further researchon the application of the algorithm in the spectrum aggregation OFDM system provedthat the algorithm uses multi-dimensional link quality matrix can represent a morecomplex channel state information. At last a adaptive spectrum aggregation scheme isdesigned for spectrum aggregation OFDM system.Secondly,for the requirements of test system about adaptive transmission, theachieve adaptive transmission scheme is designed and realized based on spectrumaggregation test system,including the timing of the principle of adaptive transmission scheme, the adaptive transmission frame structure and the adaptive transmission schemesystem terminal interface software, the underlying communication and terminalinterface software is realized too.Finally, the system is tested based on spectrum aggregation under the Gaussianchannel and the typical fading channel environment channel, test system performanceunder different conditions and the feasibility, and correctness of adaptive transmissionscheme is validated.