I mua i te mārama ki te hangarau PAM4, he aha te hangarau whakarerekētanga? Ko te hangarau whakarerekētanga te tikanga o te huri i ngā tohu turanga (ngā tohu hiko mata) hei tohu tuku. Hei whakarite i te whai huatanga o te whakawhitiwhiti kōrero me te whakakore i ngā raruraru i roto i te tuku tohu tawhiti, me whakawhiti te whānuitanga tohu ki tētahi hongere auau-tiketike mā te whakarerekētanga mō te tuku.
Ko te PAM4 he tikanga whakarerekētanga whānuitanga o te pāorooro (PAM) tuawhā o ngā raupapa.
Ko te tohu PAM tētahi o ngā hangarau tuku tohu rongonui i muri i te NRZ (Non Return to Zero).
E rua ngā taumata tohu e whakamahia ana e te tohu NRZ, teitei me te iti, hei tohu i te 1 me te 0 o te tohu arorau mamati, ā, ka taea te tuku i te 1 moka o ngā mōhiohio arorau mō ia huringa karaka.
E whā ngā taumata tohu rerekē e whakamahia ana e te tohu PAM4 mō te tuku tohu, ā, ka taea e ia huringa karaka te tuku i ngā moka mōhiohio arorau e rua, arā, 00, 01, 10, me te 11.
Nō reira, i raro i ngā āhuatanga tere moka ōrite, ko te tere moka o te tohu PAM4 e rua te nui ake i te tohu NRZ, e rua te pai o te tuku me te whakaiti i ngā utu.
Kua whānuitia te whakamahinga o te hangarau PAM4 i roto i te ao o te hononga tohu tere-teitei. I tēnei wā, kei reira ngā waeine whakawhiti whatu 400G e hangai ana ki te hangarau whakarerekētanga PAM4 mō te pokapū raraunga me te waeine whakawhiti whatu 50G e hangai ana ki te hangarau whakarerekētanga PAM4 mō te whatunga hononga 5G.
Ko te tukanga whakatinanatanga o te waeine whakawhiti whatu 400G DML e hangai ana ki te whakarerekētanga PAM4 e whai ake nei: i te wā e tuku ana i ngā tohu waeine, ka whakaurua ngā hongere 16 o ngā tohu hiko 25G NRZ i whiwhi mai i te waeine atanga hiko, ka tukatukahia i mua e te tukatuka DSP, kua whakarerekētia e te PAM4, ā, ka whakaputahia e 8 ngā hongere o ngā tohu hiko 25G PAM4, ka utaina ki runga i te maramara taraiwa. Ka hurihia ngā tohu hiko tere-teitei ki ngā hongere 8 o ngā tohu whatu tere-teitei 50Gbps mā roto i ngā hongere taiaho 8, ka whakakotahihia e te multiplexer wehenga roangaru, ā, ka hangaia ki te hongere 1 o te putanga tohu whatu tere-teitei 400G. I te wā e whiwhi ana i ngā tohu waeine, ka whakaurua te tohu whatu tere-teitei 400G 1-hongere i whiwhi mā roto i te waeine atanga whatu, ka hurihia hei tohu whatu tere-teitei 8-hongere 50Gbps mā roto i te demultiplexer, ka whiwhihia e te kaiwhiwhi whatu, ā, ka hurihia hei tohu hiko. I muri i te whakaora karaka, te whakanui, te whakataurite, me te tango PAM4 e te maramara tukatuka DSP, ka hurihia te tohu hiko ki ngā hongere 16 o te tohu hiko 25G NRZ.
Whakamahia te hangarau whakarerekētanga PAM4 ki ngā kōwae whatu 400Gb/s. Ka taea e te kōwae whatu 400Gb/s e hangai ana ki te whakarerekētanga PAM4 te whakaiti i te maha o ngā taiaho e hiahiatia ana i te pito tuku, ā, ka whakaitihia hoki te maha o ngā kaiwhiwhi e hiahiatia ana i te pito whiwhi nā te whakamahinga o ngā tikanga whakarerekētanga taumata-teitei ki te whakataurite ki te NRZ. Ka whakaitihia e te whakarerekētanga PAM4 te maha o ngā wāhanga whatu i roto i te kōwae whatu, ka taea te kawe mai i ngā painga pēnei i te iti o ngā utu huihuinga, te iti o te kai hiko, me te iti o te rahi o te takai.
He nui te hiahia mō ngā kōwae whatu 50Gbit/s i roto i ngā whatunga tuku me te whakahokinga 5G, ā, kua whakamahia he otinga e hangai ana ki ngā taputapu whatu 25G me te tāpiri atu ki te hōputu whakarerekētanga kaha pāoro PAM4 hei whakatutuki i ngā whakaritenga whānui iti te utu me te whānui teitei.
I te whakaahuatanga o ngā tohu PAM-4, he mea nui kia aro ki te rerekētanga i waenga i te tere paowa me te tere moka. Mō ngā tohu NRZ tuku iho, nā te mea kotahi te tohu e tuku ana i te moka kotahi o ngā raraunga, he rite tonu te tere moka me te tere paowa. Hei tauira, i roto i te 100G Ethernet, mā te whakamahi i ngā tohu e whā 25.78125GBaud mō te tuku, ko te tere moka i runga i ia tohu he 25.78125Gbps hoki, ā, ka tutuki i ngā tohu e whā te tuku tohu 100Gbps; Mō ngā tohu PAM-4, nā te mea kotahi te tohu e tuku ana i te 2 moka raraunga, ko te tere moka ka taea te tuku he rua te tere paowa. Hei tauira, mā te whakamahi i ngā hongere e 4 o ngā tohu 26.5625GBaud mō te tuku i roto i te 200G Ethernet, ko te tere moka i runga i ia hongere he 53.125Gbps, ā, e 4 ngā hongere o ngā tohu ka taea te whakatutuki i te tuku tohu 200Gbps. Mō te 400G Ethernet, ka taea te whakatutuki mā te 8 ngā hongere o ngā tohu 26.5625GBaud.
Wā tuku: Hanuere-02-2025