EVM: Chidule cha Error Vector Magnitude, kutanthauza kukula kwa vekitala yolakwika.
Kutumiza kwa ma frequency band a digito ndikusinthira siginecha ya baseband kumapeto kotumiza, kuitumiza pamzere kuti itumizidwe, kenako ndikuyitsitsa pamapeto olandila kuti abwezeretse chizindikiro choyambirira cha baseband. Pochita izi, cholakwika chosinthira chomwe chimapangidwa ndi modulator, mtundu wa zida za RF, phokoso lotsekeka lotsekeka (PLL), kusokoneza kwa PA, phokoso lamafuta, ndi kapangidwe ka ma module onse amatulutsa ma vector olakwika (EVM). EVM ikhudza kwambiri mtundu wa ma siginecha osinthidwa, motero projekiti yoyeserera yaukadaulo ndi imodzi mwazinthu zofunika pakuyesa kwa RF.
EVM imatanthawuza makamaka kuyandikana pakati pa gawo la IQ lomwe limapangidwa pomwe chotumizira chimatsitsa chizindikiro ndi gawo loyenera la siginecha. Ndi chizindikiro cha khalidwe la chizindikiro chosinthidwa. Nthawi zambiri, vekitala yolakwika imakhudzana ndi machitidwe osinthika a M-ary I/Q monga QPSK, ndipo nthawi zambiri amawonetsedwa ndi chithunzi cha "nyenyezi" cha I / Q chazizindikiro zotsitsa.
Vuto la vekitala yolakwika [EVM] limatanthauzidwa ngati chiŵerengero cha muzu wotanthauza lalikulu lalikulu la mphamvu yapakati ya siginecha yolakwika kupita ku muzu kumatanthauza ukulu wapakati pa mphamvu yapakati ya siginecha yoyenera ndipo imawonetsedwa ngati peresenti. EVM yaying'ono, imakhala yabwinoko chizindikiro cha chizindikiro.
Vuto la ma vector amplitude ndikupatuka pakati pa mawonekedwe oyezedwa ndi ma waveform opangidwa mongoyerekeza. Ma waveform onsewa ali ndi bandwidth ya 1.28 MHz ndi coefficient-off-off ya 0.22. Ma waveform awiriwa amasinthidwanso posankha ma frequency, gawo lamtheradi, matalikidwe amtheradi, ndi nthawi ya wotchi ya chip kuti muchepetse vector yolakwika. Nthawi yoyezera ndi nthawi imodzi. Kuchulukitsa kwa vekitala yolakwika sikuyenera kupitilira 17.5%.
Cholinga cha mayesowo ndikuwona ngati mawonekedwe a waveform opangidwa ndi transmitter ndi olondola mokwanira kuti wolandila apeze momwe amalandirira omwe adanenedwa.
Awa ndi mawu oyamba a EVM ochokera ku Shenzhen HDV Optoelectronic Technology Co., Ltd., kampani yolumikizirana ndi kuwala yomwe imapanga zinthu zolumikizirana. Takulandilani kufunsani