EVM: ka pōkole o Error Vector Magnitude, ʻo ia hoʻi ka nui o ka vector hala.
ʻO ka hoʻouna ʻana i ka alapine hōʻailona kikohoʻe e hoʻololi i ka hōʻailona baseband ma ka hopena o ka hoʻouna ʻana, e hoʻouna iā ia i ka laina no ka hoʻouna ʻana, a laila demodulate ia ma ka hopena e hoʻihoʻi i ka hōʻailona baseband kumu.Ma kēia kaʻina hana, ʻo ka hewa modulation i hana ʻia e ka modulator, ka maikaʻi o nā mea RF, ka leo o ka loop-locked loop (PLL), ka hopena distortion PA, ka walaʻau wela, a me ka hoʻolālā modulator e hana i nā vectors hewa (EVM).E loaʻa i ka EVM ka hopena nui i ka maikaʻi o nā hōʻailona modulated, no laila ʻo ka papahana hoʻāʻo maikaʻi modulation kekahi o nā mea nui o ka hoʻāʻo RF.
E pili ana ʻo EVM i ka pili kokoke i waena o ka ʻāpana IQ i hana ʻia i ka wā e hoʻokaʻawale ai ka transmitter i ka hōʻailona a me ka ʻāpana hōʻailona kūpono.He hōʻailona ia o ka maikaʻi o ka hōʻailona modulated.ʻO ka hapa nui o ka manawa, pili ka vector hewa me nā ʻōnaehana modulation M-ary I/Q e like me QPSK, a hōʻike pinepine ʻia e kahi kiʻi "hōkū" I / Q o nā hōʻailona demodulation.
ʻO ka amplitude vector hala [EVM] ua wehewehe ʻia ʻo ia ka lākiō o ke kumu mean square value o ka mana awelika o ka hōʻailona vector hala i ke kumu kumu huinahā like o ka mana awelika o ka hōʻailona kūpono a ua hōʻike ʻia ma ka pākēneka.ʻO ka liʻiliʻi o ka EVM, ʻoi aku ka maikaʻi o ka hōʻailona.
ʻO ka amplitude vector hala ka ʻokoʻa ma waena o ke ʻano nalu i ana ʻia a me ka ʻano nalu i hoʻololi ʻia.Loaʻa nā hawewe ʻelua i ka bandwidth o 1.28 MHz a me kahi helu ʻōwili o 0.22.Hoʻololi hou ʻia nā ʻano nalu ʻelua ma ke koho ʻana i ke alapine, ka pae piha, ka amplitude piha, a me ka manawa o ka uaki chip e hōʻemi i ka vector hala.ʻO ka wā ana ʻana he kau manawa hoʻokahi.ʻAʻole ʻoi aku ka nui o ka amplitude vector hapa liʻiliʻi ma mua o 17.5%.
ʻO ke kumu o ka hoʻāʻo ʻana ʻo ka ʻike inā pololei ka nalu i hana ʻia e ka transmitter no ka loaʻa ʻana o ka hana hoʻokipa i ʻōlelo ʻia.
He hoʻolauna kēia iā EVM mai Shenzhen HDV Optoelectronic Technology Co., Ltd., kahi hui kamaʻilio optical e hana i nā huahana kamaʻilio.Welina mai ekukakuka