基于多径信道的thdsuwb系统性能分析.docx

扬州大学硕十论文
ABSTRACT
The impulse radio ultra wideband(IR-UWB)technology uses ultra—short pulses to transmit signal,and has a huge channel capacity and Can convey hi gh—speed performance of TH/DS—UWB systems in the multi—path channel is studied in this thesis. The primary contents of the thesis are as following.
In the AWGN channel without multi-path,the formulas of bit error rate(BER) for both time hopping binary pulse position ultra—wideband(TH BPPM—UWB)and time hopping binary pulse amplitude ultra—wideband(TH BPAM-UWB)systems are deduced based on the methods of soft detection and hard ,the property of the two systems is also investigated through simulation results show that their performance is improved obviously as the pulse—repeated times increase,and the characteristic of the system using soft detection is prior to that of the system using
hard detection.
Through using the UWB indoor channel model proposed by IEEE study group,the performance improvement of the binary pulse position modulation time hopping ultra-wideband(2PPM—TH UWB)systems is analyzed in the case of
employing multiple receive on the Standard Gaussian Approximation
(SGA).the BER formula in the 2PPM-TH UWB system using the spatial diversity is ideal power control,the diversity performance of 2PPM—TH—UWB systems iS evaluated for different numbers of antenna elements and selected multipath. The simulation results indicate that the system property gets better when the number of antenna elements and Rake fingers increases,and the effects of the spatial diversity
upon improving system performance are better than that of the temporal diversity. Through using the UWB indoor channel model proposed by IEEE
study group,the characteristic of two kinds of ultra wide band systems,namely Direct Sequence Multiple Access(DS-MA)and Time Hopping Multiple Access(TH—MA),is researched by the simulation results