Diversity GainsAcross LineofSight andRich Scattering Environments from Space-Polarizati on-Time Codes

Space-time codes built outofAlamouti components theperformance isdominated bythe"angles" between the havebeenadopted inwireless standards suchasUMTS,IEEE component Alamouti channels.(see (6)formoredetails) 802.11n andIEEE802.16 wheretheyfacilitate higher datarates Ourapproach alsoprovides insight intothevalueofpo- through multiplexing ofparallel datastreams andtheaddition of larization diversity atthephysical layer. Standard wireless twoormoreantennas atthereceiver thatperform interference comuiation syst use a ler.andaandla cancellation. Thispaperprovides newtheoretical insight intocommunication systems useasingle transmit antenna anda analgorithm forinterference cancellation through aBayesiansingle receive antenna withlinear vertical polarization. Many analysis thatexpresses performance asafunction ofSNR in WiFiaccess points exploit polarization implicitly inawaythat termsofthe"angles" between different space-time codeddata isanalogous toselection diversity andlinear combining tech- streams. Ourapproach provides insights intothecoupling of . . . channel coding tospatial andpolarization degrees offreedom.niques applied intraditional receiver (space) diversity (7). The signal islaunched withasingle polarization, thepropagation