Crosslayer Disign In Cooperative MIMO System With Multiple-antenna Terminals

In recent years,users get better service along with the development of mobilecommunications technology.They demand for reliability and validity of thesystem.However, problems inherent in wireless communications, such as radiochannel randomness caused by frequency selective fading, as well as theincreasingly tense bandwidth resources, not only limite the spectral efficiency andsystem capacity enhancement,but also spur the development of new technologies tosolve these problems.Multi-antenna diversity techniques which means a terminal configuration ofmultiple antennas can improve system reliability, data rates and system capacitywithout consuming additional bandwidthcosting.It has been becoming one of thecurrent research focus.However, a terminal configuration with multiple antennaswill be subject to the restrictions of the antenna correlation and physicallimiting,This problem urged people to think about ways to use existing systems toachieve the effect of multi-antenna systerm.Cooperative diversity came into being.Cooperative diversity make the use of cooperative transmission.which means theantenna of the different users virtually become a multi-antenna transmissionsystems.It will also achieve the diversity and multiplexing gain, improving theeffectiveness and reliability of the system. At the same time, due to the hierarchicaldesign principles of traditional communication systems, system optimization cannot be integrated to consider all layers.Cross-layer design breaks the limits of thelayer, using the correlation between the protocol layer to delivery statusinformation,coordinates the configuration between the layers to optimize the systemsettings to ensure that resource utilization and QoS requirements.This paper firstly introduces the basic theory of cooperative diversity, such assub-collections and the way the collaborative model,forwarding protocols andspace-time coding theory, and then introduces the basic theory and the twotechniques commonly used in cross-layer design of the cross-layer design: thephysical layer adaptive code modulation (Adaptive Modulation and Coding) andlink layer hybrid automatic repeat request (Hybrid Automatic Repeat Request). Onthe basis of theoretical analysis, introuduces an effective cross-layer design forcooperative MIMO system for multi-antenna terminal, using the physical layeradaptive modulation and coding and link-layer hybrid automatic retransmissionrequest to optimization to achieve a better system performance, simulation resultsshow that the cross-layer design in this paper can improve the throughput performance of multi-antenna terminal collaborative MIMO system,with meetingthe requirements of the packet error rate to effectively and also proved comparin g tothe non-cooperative system, cooperative diversity can reduce system packet errorrate.