Isingeniso kubuchwepheshe be-PAM4

Ngaphambi kokuqonda ubuchwepheshe be-PAM4, yini ubuchwepheshe bokushintshana? Ubuchwepheshe be-Modanyuty yindlela yokuguqula amasiginali we-baseband (amasiginali kagesi aluhlaza) abe amasiginali wokuhambisa. Ukuze uqinisekise ukusebenza kokuxhumana futhi ukunqoba izinkinga zokudluliselwa kwesiginali yebanga elide, kuyadingeka ukudlulisa isibonakaliso sesiginali esiteshini esivame kakhulu ngokushintshashintsha.

I-PAM4 iyindlela yesine ye-Pulpse Amplitude Modulation (PAM) yokushintshashintsha.

I-Pam Signal ubuchwepheshe bokudlulisa isizinda esidumile ngemuva kwe-NRZ (ukungabuyi ku-zero).

Isiginali ye-NRZ isebenzisa amazinga amabili wesiginali, aphezulu futhi aphansi, ukumela i-1 no-0 yesiginali ye-Digital Logic, futhi ingadlulisela okungu-1 okuncane kolwazi lokuqondayo ngomjikelezo wewashi ngalinye.

Isiginali yePam4 isebenzisa amazinga ahlukene wesiginali okudlulisela kwesiginali, futhi umjikelezo ngamunye wewashi ungadlulisela amabhithi ama-2 wolwazi olunengqondo, okungukuthi 00, 01, 10, no-11.
Ngakho-ke, ngaphansi kwezimo ezifanayo ze-baud, isilinganiso se-PAM4 Signal kabili ukuthi sesiginali ye-NRZ kabili, esiphinda kabili ukusebenza kahle futhi sinciphise ngempumelelo izindleko.

Ubuchwepheshe be-PAM4 busetshenziswe kabanzi emkhakheni wokuxhumana ngesiginali esiphezulu. Njengamanje, kunemodyuli ye-400G Optical transceiver esekelwe kubuchwepheshe be-PAM4 yokushintshana ngesikhungo sedatha kanye ne-50g Optical Transceiver module ngokusekelwe kubuchwepheshe be-PAM4 yokushintshana kwe-InterConnection Network ye-5G Inethiwekhi ye-5G.

Inqubo yokuqalisa ye-400G DML Optical Transceiver module ngokusekelwe ku-PAM4 Ukushintshana ngokulandelayo: Lapho kudluliswa amasiginali weyunithi kagesi, kufakwe ama-DSP processor, futhi akhipha iziteshi eziyi-8 ze-25G Pam4 kagesi, ezilayishwe kwi-chip yomshayeli. Amasiginali kagesi anesivinini esiphakeme aguqulwa abe yiziteshi eziyi-8 zamasiginali we-50GBPS aphezulu aphezulu ngeziteshi eziyi-8 zama-lasers, ahlanganiswe yisiteshi esiphakeme, futhi ahlelwe esiteshini esingu-400g esisheshayo se-400g ephezulu ye-Optical Signal Expert. Lapho uthola amasiginali weyunithi, isikhangiso esitholwe esingu-400g esiphakeme se-400G esiphakeme se-Optical sifakwa ngokusebenzisa iyunithi ye-Optical Interface, iguqulwe ibe yisiginali ye-50GBBS ephezulu yejubane eliphakeme nge-demilteriplexxer, itholwe yi-Optical Optiver, futhi iguqulwe ibe isibonakaliso sikagesi. Ngemuva kokululama kwewashi, ukukhulisa, ukulingana, kanye ne-pam4 demomali nge-chip ye-DSP yokucubungula, isiginali kagesi iguqulwa ibe yiziteshi eziyi-16 zesiginali kagesi ka-25G NRZ.

Faka isicelo sobuchwepheshe be-PAM4 sokushintshana kumamojula we-400GB / S. Imodyuli ye-400GB / S Optical esekelwe ku-PAM4 yokushintshashintsha inganciphisa inani lama-lasers adingekayo ekulethweni kokudluliselwa futhi ngokuhambisana nenombolo yokuthola amasu atholakalayo ngenxa ye-NRZ. Ukushintshwa kwe-PAM4 kunciphisa inani lezakhi ze-Optical kumodyuli ye-Optical, ezingaletha izinzuzo ezinjengezindleko zomhlangano eziphansi, ukusetshenziswa kwamandla okuncishisiwe.

Kunesidingo samamojula we-50GBIT / S Optical amamojula kumanethiwekhi we-5G kanye namanethiwekhi asemuva, kanye nesixazululo esisekelwe kumadivayisi we-25G Optical futhi angezelwe yi-Pam4 Pulse Amplitude Modulation formation amukelwe ukufezekisa izidingo zama-bandwidth eziphansi.

Lapho kuchazwa amasiginali kaPam-4, kubalulekile ukunaka umehluko phakathi kwesilinganiso se-baud kanye ne-bit rate. Kwamasiginali endabuko we-NRZ, ngoba uphawu olulodwa ludlulisela idatha eyodwa encane, inani elincane kanye ne-Baud Rate afanayo. Isibonelo, ku-100g Ethernet, usebenzisa amasignali amane angama-25.78125gbaad ukuhambisa, inani elincane kusiginali ngayinye libuye libe ngama-25.78125gbs, futhi izibonakaliso ezine zenzele ukuhanjiswa kwesiginali engu-100gbs; Okwezibonakaliso ze-PAM-4, ngoba uphawu olulodwa ludlulisa izingcezu zedatha ezi-2, isilinganiso esincane esingadluliswa siyizinga le-baud. Isibonelo, usebenzisa iziteshi ezi-4 zamasignali angama-26.5625gbaad wokudlulisela ku-200g Ethernet, isilinganiso esincane esiteshini ngasinye singama-53.125gbps, neziteshi ezi-4 zamasiginali zingafinyelela ukuhanjiswa kwesiginali ye-200GBPS. Okwe-400g Ethernet, kungatholakala ngeziteshi eziyi-8 zezimpawu ezingama-26.5625gbaad.