RSSI ndiyo chidimbu cheReceived Signal Strength Indication.Iyo yakagamuchirwa chiratidzo chesimba chimiro chinoverengerwa nekuenzanisa maitiro maviri;ndiko kuti, inogona kushandiswa kuona kuti simba rechiratidzo rakasimba sei kana risina simba richienzaniswa neimwe chiratidzo.
Iyo yekuverenga formula yeRSSI ndeye: 10 * log (W1/W2)
Nhamba yekutanga yerogi ndeye 10 nekukasira, W1 inomiririra simba 1 (kazhinji iro simba rekuyerwa), uye W2 inomiririra simba 2 (yakajairwa simba).Kukosha kwemhedzisiro chiratidzo chekuti yakawanda sei W1 yakakura kana idiki pane W2.Iyo unit iDB, iyo isina kukosha kwayo asi inomiririra kukosha kwakasiyana.Inogona kunzwisiswa semusiyano pakati pechiyero cheW1 neW2.Iyi inhaka yeabstract isina chaiyo unit.Ehe, kana tichienzanisa W1 neW2 ndeechikamu chimwe chete, asi zvisinei kuti ndeipi unit inoshandiswa, mutsauko uripo pakati pawo imwechete DB nhamba.
Special case:kana W2 iri 1, chikamu cheRSSI chinogona kutariswa zvinoenderana nechikamu cheW2.Kana W2 iri 1mw, chikamu cheRSSI chiri dBm;kana W2 iri 1w, iyo unit yeRSSI iri dbw.Ipapo ndipo apo W2 iri 1mw kana 1w, chikamu cheW1 chinogona kuchinjwa kubva kuMW kana w kuenda kudbm kana dbw.
semuyenzaniso:Kukosha kwekushandura 40000 MW yesimba ku dBm igumi * log (40000/1mw) 46 dBm.
Saka sei kusuma DB?
1.Chekutanga pane zvese, basa rinonyanya kujeka nderokudzikisa kukosha kwekufambisa kuverenga nekunyora, senge unotevera muenzaniso:
0.000000000000001 = 10*log(10^-15) =-150 dB
2.Izvo zvakare zviri nyore kuverenga zvidiki zvidiki: kuwanda kunoshandiswa mukukurisa-nhanho, nepo DB inoshandisa kuwedzera nekuda kwelogarithmic log.Semuyenzaniso, kana ukaswededza ka100 wozoswededza ka20, kukwidziridzwa kwacho kunosvika 100 * 20 = 2000, asi kuverenga kweDB i10 * log (100) = 20, 10 * log (20) = 13, uye kukwidziridzwa kwese kuri 20+13=33db
3.Yakanyatsojeka kune manzwiro chaiwo.Apo nheyo yesimba iri 1, 10 * log (11/1) ≈ 10.4db inowedzera kubva 1 kusvika 10. Kana nheyo iri 100, 10 * log (110/100) ≈ 0.4db inowedzera.Kana hwaro hwachinja, kumwe kukwidziridzwa kwakafanana kunokura nenzira dzakasiyana, dzinoenderana nezvinoonekwa nevanhu.
RSSI chiratidzo chekugamuchira simba rechiratidzo.Kureva kuti, iyo yakakura kukosha kweRSSI, iyo yakakura iyo yakagamuchirwa chiratidzo chesimba.Nekudaro, hazvireve kuti iyo yakakura kukosha kweRSSI, zviri nani.Nekuti kazhinji inodiwa kuchengetedza rakakura kudaro simba, akawanda anodzokorora anodiwa pakati, uye mutengo wakakwira.Hazvidikanwi.Kazhinji, ingori 0 ~ - 70dbm.
Izvo zviri pamusoro ndiyo tsananguro yeReceived Signal Strength Indication (RSSI) ruzivo rwakaunzwa neShenzhen HDV Phoelectric Technology Co., Ltd., inova kambani inogadzira kutaurirana yemagetsi.Tinokugamuchiraikubvunzaisu kuitira mabasa emhando yepamusoro.