{"id":708,"date":"2025-11-01T09:55:54","date_gmt":"2025-11-01T07:55:54","guid":{"rendered":"https:\/\/eugo.ro\/?p=708"},"modified":"2025-11-01T17:52:08","modified_gmt":"2025-11-01T15:52:08","slug":"despre-placile-radio","status":"publish","type":"post","link":"https:\/\/eugo.ro\/?p=708","title":{"rendered":"Placile radio Ericsson"},"content":{"rendered":"<p>&nbsp;<\/p>\n<p>De\u0219i detaliile specifice ale arhitecturii interne ale pl\u0103cilor radio Ericsson sunt protejate de secrete comerciale \u0219i pot varia de la o genera\u021bie la alta (de exemplu, \u00eentre sistemele GSM, UMTS, LTE sau 5G), se poate face o descriere general\u0103 a modului \u00een care func\u021bioneaz\u0103 aceste module \u00een contextul sta\u021biilor de baz\u0103 \u00een telefonia mobil\u0103.<\/p>\n<p>Iat\u0103 c\u00e2teva idei generale despre arhitectura \u0219i principiul de func\u021bionare:<\/p>\n<p><em><strong>Func\u021bie \u0219i rol<\/strong><\/em><\/p>\n<ul>\n<li>Scopul pl\u0103cilor radio este de a efectua conversia semnalelor dintre procesarea digital\u0103 (baseband) \u0219i semnalele RF (radiofrecven\u021b\u0103) care se propag\u0103 prin aer, \u00een ambele direc\u021bii (transmitere \u0219i recep\u021bie).<\/li>\n<\/ul>\n<ul>\n<li>Aceste pl\u0103ci sunt parte din echipamentele din sta\u021biile radio de baz\u0103 care conecteaz\u0103 re\u021beaua mobil\u0103 la utilizatori, asigur\u00e2nd modularea, demodularea, conversia de frecven\u021b\u0103 \u0219i amplificarea necesare.<\/li>\n<\/ul>\n<p><em><strong>Blocuri func\u021bionale principale<\/strong><\/em><\/p>\n<p>De\u0219i implementarea poate fi foarte sofisticat\u0103, o schem\u0103 bloc simplificat\u0103 a unei pl\u0103ci radio (pentru transmitere \u015fi recep\u0163ie) poate fi rezumat\u0103 astfel:<\/p>\n<p><strong>LAN\u021a de TRANSMITERE (TX):<\/strong><\/p>\n<p><em><strong>1. Unit\u0103\u021bi de procesare digital\u0103 (DSP\/FPGA):<\/strong><\/em><\/p>\n<ul>\n<li>Preia datele de la sec\u021biunea baseband.<\/li>\n<\/ul>\n<ul>\n<li>Realizeaz\u0103 modularea (ex.: QAM, GMSK, etc., \u00een func\u021bie de tehnologie) \u0219i alte corec\u021bii\/adapt\u0103ri (cum ar fi pre-codarea).<\/li>\n<\/ul>\n<p><em><strong>2. Convertor digital-analogic (DAC):<\/strong><\/em><\/p>\n<ul>\n<li>Transform\u0103 semnalul digital modulat \u00eentr-un semnal analogic de frecventa intermediara (IF \u2013 Intermediate Frequency) sau chiar direct \u00een forma aproape a semnalului RF.<\/li>\n<\/ul>\n<p><em><strong>3. Etapa de up-conversion:<\/strong><\/em><\/p>\n<ul>\n<li>Un convertor de frecven\u021b\u0103 (mixer) care combin\u0103 semnalul analogic (IF \u2013 Intermediate Frequency) cu un semnal de la oscilatorul local (LO) pentru a genera semnalul la frecven\u021ba RF dorit\u0103.<\/li>\n<\/ul>\n<p><em><strong>4. Filtre \u0219i amplificatoare intermediare:<\/strong><\/em><\/p>\n<ul>\n<li>Filtrele selec\u021bioneaz\u0103 benzile dorite, iar ETAs (de exemplu, amplificatorul de putere) amplific\u0103 semnalul pentru a fi transmis cu puterea necesar\u0103.<\/li>\n<\/ul>\n<p><em><strong>5. Linia de transmisie c\u0103tre anten\u0103:<\/strong><\/em><\/p>\n<ul>\n<li>Asigur\u0103 c\u0103 semnalul RF este transmis c\u0103tre anten\u0103 cu caracteristici de impedan\u021b\u0103 adecvate.<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<p><strong>LAN\u021a de RECEP\u021aIE (RX):<\/strong><\/p>\n<p><em><strong>1. Receptia semnalului RF:<\/strong><\/em><\/p>\n<ul>\n<li>Antena capteaz\u0103 semnalul cu caracteristicile de band\u0103 larg\u0103 ale sistemului.<\/li>\n<\/ul>\n<p><em><strong>2. Amplificator cu zgomot redus (LNA):<\/strong><\/em><\/p>\n<ul>\n<li>Amplific\u0103 semnalul recep\u021bionat, \u00eencerc\u00e2nd s\u0103 p\u0103streze raportul semnal\/zgomot c\u00e2t mai bun.<\/li>\n<\/ul>\n<p><em><strong>3. Etapa de down-conversion:<\/strong><\/em><\/p>\n<ul>\n<li>Un mixer combin\u0103 semnalul amplificat cu un semnal de la oscilatorul local pentru a-l converti de la frecven\u021ba RF la o frecven\u021b\u0103 intermediar\u0103 (IF).<\/li>\n<\/ul>\n<p><em><strong>4. Filtrare \u0219i amplificare IF:<\/strong><\/em><\/p>\n<ul>\n<li>Se folosesc filtre pentru a exclude interferen\u021bele \u0219i se amplific\u0103 semnalul IF, preg\u0103tindu-l pentru conversie digital\u0103.<\/li>\n<\/ul>\n<p><em><strong>5. Convertor analog-digital (ADC):<\/strong><\/em><\/p>\n<ul>\n<li>Semnalul analogic IF este converit in semnal digital pentru a putea fi procesat de DSP(blocul de procesare digitala) sau sistemele de control.<\/li>\n<\/ul>\n<p><em><strong>6. Blocul de procesare digital\u0103 (DSP\/FPGA):<\/strong><\/em><\/p>\n<ul>\n<li>Demoduleaz\u0103 \u0219i decodeaz\u0103 semnalul \u00een formatul baseband, extr\u0103g\u00e2nd informa\u021bia transmis\u0103.<\/li>\n<\/ul>\n<p><em><strong>3. Oscilatoare locale \u0219i sintetizatoare de frecven\u021b\u0103<\/strong><\/em><\/p>\n<ul>\n<li>Sintetizatoarele(oscilatoarele locale) sunt esen\u021biale pentru func\u021biile de up-conversion \u0219i down-conversion, asigur\u00e2nd stabilitatea \u00een frecven\u021b\u0103 \u0219i precizia semnalului.<\/li>\n<\/ul>\n<ul>\n<li>Tehnologia modern\u0103, inclusiv tehnici de calibrare \u0219i compensare a varia\u021biilor de temperatur\u0103, este integrat\u0103 pentru a garanta performan\u021be constante.<\/li>\n<\/ul>\n<p><em><strong>4. Integrarea \u015fi controlul<\/strong><\/em><\/p>\n<ul>\n<li>Pl\u0103cile radio Ericsson sunt \u00een general controlate de microcontrolere sau procesoare dedicate care gestioneaz\u0103 sincronizarea, compensarea erorilor (ex.: eroarea fazic\u0103) \u0219i adaptarea puterii, \u00eentre alte func\u021bii critice.<\/li>\n<\/ul>\n<ul>\n<li>Comunica\u021bia \u00eentre modulul baseband \u0219i lan\u021burile RF se face prin protocoale digitale interconectate, asigur\u00e2nd coordonarea optim\u0103 a transmisiilor \u00een re\u021bea.<\/li>\n<\/ul>\n<p><em><strong>5. Principiul de func\u021bionare<\/strong><\/em><\/p>\n<p>Rolul principal al unei pl\u0103ci radio este s\u0103 fac\u0103 leg\u0103tura dintre semnalul digital (venit din unitatea de band\u0103 de baz\u0103) \u0219i semnalul radio transmis sau recep\u021bionat prin anten\u0103.<\/p>\n<p><em><strong>Func\u021biile de baz\u0103 sunt:<\/strong><\/em><\/p>\n<ul>\n<li>Conversie digital-analogic\u0103 (DAC) pentru semnalul de emisie.<\/li>\n<\/ul>\n<ul>\n<li>Up-conversion: transpunerea semnalului din frecven\u021be intermediare (IF) \u00een frecven\u021ba radio (RF).<\/li>\n<\/ul>\n<ul>\n<li>Amplificare de putere (PA \u2013 Power Amplifier) pentru a transmite semnalul c\u0103tre anten\u0103 cu nivelul necesar.<\/li>\n<\/ul>\n<ul>\n<li>Filtrare \u0219i duplexare: separarea canalelor de emisie \u0219i recep\u021bie, eliminarea zgomotelor \u0219i a interferen\u021belor.<\/li>\n<\/ul>\n<ul>\n<li>Down-conversion: transpunerea semnalului recep\u021bionat din RF \u00een IF sau direct \u00een band\u0103 de baz\u0103.<\/li>\n<\/ul>\n<ul>\n<li>Conversie analog-digital\u0103 (ADC) pentru semnalul recep\u021bionat.<\/li>\n<\/ul>\n<ul>\n<li>Control \u0219i calibrare automat\u0103 (AGC \u2013 Automatic Gain Control, compensarea temperaturii, linearizare).<\/li>\n<\/ul>\n<p>&nbsp;<br \/>\n<strong><\/p>\n<p>Schema bloc simplificat\u0103 a unei pl\u0103ci radio Ericsson<\/p>\n<p><\/strong><br \/>\n<code><br \/>\nSemnal digital (Baseband)<br \/>\n        \u2502<br \/>\n        \u25bc<br \/>\n   [DAC + Filtru]<br \/>\n        \u2502<br \/>\n        \u25bc<br \/>\n   [Up-Converter] \u2500\u2500\u25ba [Amplificator de Putere (PA)] \u2500\u2500\u25ba [Filtru RF \/ Duplexor] \u2500\u2500\u25ba Anten\u0103 (Tx)<br \/>\n        \u2502<br \/>\n        \u2502<br \/>\nAntena (Rx) \u2500\u2500\u25ba [Filtru RF \/ Duplexor] \u2500\u2500\u25ba [LNA \u2013 Low Noise Amplifier] \u2500\u2500\u25ba [Down-Converter] \u2500\u2500\u25ba [ADC] \u2500\u2500\u25ba Semnal digital (Baseband)<br \/>\n<\/code><\/p>\n<ul>\n<strong><\/p>\n<p>\u00cen contextul re\u021belelor mobile<\/p>\n<p><\/strong><\/p>\n<li>\u00cen <strong>GSM<\/strong>, pl\u0103cile radio gestioneaz\u0103 canale de 200 kHz \u0219i folosesc modula\u021bie GMSK.<\/li>\n<\/ul>\n<ul>\n<li>\u00cen <strong>UMTS<\/strong>, lucreaz\u0103 cu canale de 5 MHz \u0219i modula\u021bie QPSK.<\/li>\n<\/ul>\n<ul>\n<li>\u00cen <strong>LTE<\/strong>, suport\u0103 l\u0103\u021bimi de band\u0103 variabile (1,4 \u2013 20 MHz) \u0219i modula\u021bii avansate (QPSK, 16QAM, 64QAM).<\/li>\n<\/ul>\n<ul>\n<li>\u00cen <strong>5G (NR)<\/strong>, pl\u0103cile radio Ericsson sunt mult mai complexe, suport\u00e2nd <strong>MIMO masiv<\/strong> \u0219i <strong>beamforming<\/strong>, cu frecven\u021be de la sub-6 GHz p\u00e2n\u0103 la mmWave.<\/li>\n<\/ul>\n<p><strong><\/p>\n<p>Etapele proces\u0103rii semnalului de voce \u2192 RF<\/p>\n<p><\/strong><\/p>\n<p> <strong><\/p>\n<p>1. Captarea \u0219i digitalizarea vocii<\/p>\n<p><\/strong><\/p>\n<ul>\n<li> Microfonul transform\u0103 undele acustice \u00een semnal electric analogic.<\/li>\n<\/ul>\n<ul>\n<li>Codec-ul audio (de ex. AMR \u00een GSM\/UMTS, EVS \u00een LTE\/5G) face Conversie analog-digital (ADC); Compresie \u0219i codare a vocii pentru a reduce l\u0103\u021bimea de band\u0103.<\/li>\n<\/ul>\n<p><strong><\/p>\n<p> 2. Procesare \u00een band\u0103 de baz\u0103 (Baseband Processing)<\/p>\n<p><\/strong><\/p>\n<ul>\n<li><strong>Codare de canal:<\/strong> adaug\u0103 redundan\u021b\u0103 pentru corec\u021bia erorilor (FEC).<\/li>\n<\/ul>\n<ul>\n<li><strong>Intercalare (interleaving):<\/strong>redistribuie bi\u021bii pentru a rezista la erori \u00een rafal\u0103.<\/li>\n<\/ul>\n<ul>\n<li><strong>Encriptare:<\/strong> protejeaz\u0103 confiden\u021bialitatea convorbirii.<\/li>\n<\/ul>\n<ul>\n<li><strong>Mapare\/modulare digital\u0103:<\/strong> bi\u021bii sunt transforma\u021bi \u00een simboluri (GMSK \u00een GSM, QPSK\/16QAM\/64QAM \u00een LTE\/5G).<\/li>\n<\/ul>\n<ul>\n<li><strong>Formare cadru \u0219i multiplexare:<\/strong> semnalul utilizatorului este \u00eencadrat \u00een sloturi de timp sau resurse de frecven\u021b\u0103.<\/li>\n<\/ul>\n<p><strong><P>3. Conversie digital-analogic\u0103<\/p>\n<p><\/strong><\/p>\n<ul>\n<li>Semnalul digital modulat este convertit \u00een semnal analogic prin <strong>DAC<\/strong>.<\/li>\n<\/ul>\n<ul>\n<li>Se aplic\u0103 un filtru trece-jos pentru a elimina armonicile de cuantizare.<\/li>\n<\/ul>\n<p><strong><\/p>\n<p>4. Conversie \u00een frecven\u021b\u0103 intermediar\u0103 (IF) \u0219i apoi RF<\/p>\n<p><\/strong><\/p>\n<ul>\n<li><strong>Up-converter:<\/strong> transpunerea semnalului din banda de baz\u0103\/IF la frecven\u021ba radio dorit\u0103 (de ex. 900 MHz, 1800 MHz, 2100 MHz, 3500 MHz).<\/li>\n<\/ul>\n<ul>\n<li>Se folose\u0219te un oscilator local (LO) \u0219i un mixer pentru transla\u021bia de frecven\u021b\u0103.<\/li>\n<\/ul>\n<p><strong><\/p>\n<p>5. Amplificare \u0219i filtrare RF<\/p>\n<p><\/strong><\/p>\n<ul>\n<li><strong>Pre-amplificator:<\/strong> ridic\u0103 nivelul semnalului.<\/li>\n<\/ul>\n<ul>\n<li><strong>Filtru RF:<\/strong> elimin\u0103 semnalele parazite \u0219i respect\u0103 masca spectral\u0103.<\/li>\n<\/ul>\n<ul>\n<li><strong>Amplificator de putere (PA):<\/strong> cre\u0219te nivelul semnalului la zeci de wa\u021bi pentru a putea fi radiat eficient.<\/li>\n<\/ul>\n<p><strong><\/p>\n<p>6. Etajul de anten\u0103<\/p>\n<p><\/strong><\/p>\n<ul>\n<li><strong>Duplexor \/ Diplexer:<\/strong> separ\u0103 calea de emisie (TX) de cea de recep\u021bie (RX) pe aceea\u0219i anten\u0103.<\/li>\n<\/ul>\n<ul>\n<li><strong>Antena RF:<\/strong> converte\u0219te semnalul electric \u00een unde electromagnetice care se propag\u0103 \u00een spa\u021biu.<\/li>\n<\/ul>\n<p><strong><\/p>\n<p>Schema bloc simplificat\u0103 a lan\u021bului TX >\/p><\/strong><\/p>\n<p><code><br \/>\nVoce (microfon)<br \/>\n      \u2502<br \/>\n      \u25bc<br \/>\n [Codec audio: ADC + compresie]<br \/>\n      \u2502<br \/>\n      \u25bc<br \/>\n [Codare canal + criptare]<br \/>\n      \u2502<br \/>\n      \u25bc<br \/>\n [Modulator digital + multiplexare]<br \/>\n      \u2502<br \/>\n      \u25bc<br \/>\n [DAC + Filtru LPF]<br \/>\n      \u2502<br \/>\n      \u25bc<br \/>\n [Up-Converter + Oscilator Local]<br \/>\n      \u2502<br \/>\n      \u25bc<br \/>\n [Filtru RF + Pre-amplificator]<br \/>\n      \u2502<br \/>\n      \u25bc<br \/>\n [Amplificator de Putere (PA)]<br \/>\n      \u2502<br \/>\n      \u25bc<br \/>\n [Duplexor \/ Diplexer]<br \/>\n      \u2502<br \/>\n      \u25bc<br \/>\n [Antena RF]  \u2192  Radia\u021bie electromagnetic\u0103<\/p>\n<p><\/code><\/p>\n<p><strong><\/p>\n<p>Observa\u021bii importante<\/p>\n<p><\/strong><\/p>\n<ol>In <strong>GSM<\/strong>, vocea este codificat\u0103 la 13 kbps (codec Full Rate), transmis\u0103 prin GMSK.<\/ol>\n<ol>In <strong>UMTS<\/strong>, vocea trece prin AMR \u0219i este transmis\u0103 prin WCDMA (QPSK).<\/ol>\n<ol>In <strong>LTE\/5G<\/strong>, vocea este transportat\u0103 ca VoIP (VoLTE\/VoNR), deci fluxul de voce devine pachete IP, apoi este procesat ca orice alt trafic de date.<\/ol>\n<p><strong>Etapele lan\u021bului RX<\/strong><br \/>\n <em><strong>1.Captarea semnalului RF<\/strong><\/em><\/p>\n<ul>\n<li>Antena recep\u021bioneaz\u0103 undele electromagnetice din eter.<\/li>\n<\/ul>\n<ul>\n<li>Semnalul este foarte slab (microvol\u021bi), deci are nevoie de prelucrare atent\u0103.<\/li>\n<\/ul>\n<ul>\n<li>Duplexor\/Diplexer separ\u0103 calea de recep\u021bie de cea de emisie (dac\u0103 se folose\u0219te aceea\u0219i anten\u0103).<\/li>\n<\/ul>\n<p><em><strong>2. Filtrare \u0219i amplificare ini\u021bial\u0103<\/strong><\/em><\/p>\n<ul>\n<li><strong>Filtru RF:<\/strong> selecteaz\u0103 banda de frecven\u021b\u0103 dorit\u0103 \u0219i elimin\u0103 interferen\u021bele din alte benzi.<\/li>\n<\/ul>\n<ul>\n<li><strong>LNA (Low Noise Amplifier):<\/strong> amplific\u0103 semnalul recep\u021bionat cu zgomot ad\u0103ugat minim.<\/li>\n<\/ul>\n<p><em><strong>3. Conversie de frecven\u021b\u0103 (Down-Conversion)<\/strong><\/em><\/p>\n<ul>\n<li>Semnalul RF este transpus la o frecven\u021b\u0103 intermediar\u0103 (IF) sau direct \u00een band\u0103 de baz\u0103.<\/li>\n<\/ul>\n<ul>\n<li>Se folose\u0219te un mixer \u0219i un oscilator local (LO).<\/li>\n<\/ul>\n<ul>\n<li>Motivul: la frecven\u021be mai joase, semnalul poate fi filtrat \u0219i procesat mai u\u0219or.<\/li>\n<\/ul>\n<p><em><strong>4. Filtrare \u0219i amplificare IF<\/strong><\/em><\/p>\n<ul>\n<li><strong>Filtru IF:<\/strong> selecteaz\u0103 canalul dorit \u0219i elimin\u0103 zgomotele.<\/li>\n<\/ul>\n<ul>\n<li><strong>Amplificator IF:<\/strong> cre\u0219te nivelul semnalului pentru a fi detectat corect.<\/li>\n<\/ul>\n<p><em><strong>5. Conversie analog-digital\u0103<\/strong><\/em><\/p>\n<ul>\n<li>Semnalul analogic este convertit \u00een digital prin ADC.<\/li>\n<\/ul>\n<ul>\n<li>Acum poate fi procesat de circuitele digitale de band\u0103 de baz\u0103.<\/li>\n<\/ul>\n<p><em><strong>6. Procesare \u00een band\u0103 de baz\u0103 (Baseband Processing)<\/strong><\/em><\/p>\n<ul>\n<li><strong>Demodulare digital\u0103:<\/strong> extrage simbolurile din semnal (ex. GMSK, QPSK, QAM).<\/li>\n<\/ul>\n<ul>\n<li><strong>Decriptare:<\/strong> elimin\u0103 protec\u021bia criptografic\u0103.<\/li>\n<\/ul>\n<ul>\n<li><strong>De-intercalare \u0219i decodare de canal:<\/strong> reconstruie\u0219te fluxul de bi\u021bi \u0219i corecteaz\u0103 erorile.<\/li>\n<\/ul>\n<ul>\n<li><strong>Reconstruc\u021bia fluxului de voce:<\/strong> bi\u021bii sunt transforma\u021bi \u00een pachete de voce (VoIP \u00een LTE\/5G sau cadre vocale \u00een GSM\/UMTS).<\/li>\n<\/ul>\n<p><em><strong>7. Decodare audio \u0219i redare<\/strong><\/em><\/p>\n<ul>\n<li><strong>Codec audio<\/strong> (AMR, EVS etc.) decodific\u0103 fluxul digital \u00een semnal audio <strong>PCM<\/strong>.<\/li>\n<\/ul>\n<ul>\n<li>Conversie digital-analogic\u0103 (DAC).<\/li>\n<\/ul>\n<ul>\n<li><strong>Amplificator audio<\/strong> \u2192 difuzor \u2192 vocea utilizatorului.<\/li>\n<\/ul>\n<p><strong>Schema bloc simplificat\u0103 RX<\/strong><\/p>\n<p><code><br \/>\nUnd\u0103 electromagnetic\u0103<br \/>\n        \u2502<br \/>\n        \u25bc<br \/>\n [Antena] \u2500\u2500\u25ba [Duplexor\/Diplexer]<br \/>\n        \u2502<br \/>\n        \u25bc<br \/>\n [Filtru RF] \u2500\u2500\u25ba [LNA]<br \/>\n        \u2502<br \/>\n        \u25bc<br \/>\n [Mixer + Oscilator Local] \u2192 Semnal IF\/Baseband<br \/>\n        \u2502<br \/>\n        \u25bc<br \/>\n [Filtru IF + Amplificator IF]<br \/>\n        \u2502<br \/>\n        \u25bc<br \/>\n [ADC]<br \/>\n        \u2502<br \/>\n        \u25bc<br \/>\n [Demodulare + Decriptare + Decodare canal]<br \/>\n        \u2502<br \/>\n        \u25bc<br \/>\n [Codec audio + DAC]<br \/>\n        \u2502<br \/>\n        \u25bc<br \/>\n [Amplificator audio]<br \/>\n        \u2502<br \/>\n        \u25bc<br \/>\n Difuzor \u2192 Voce<br \/>\n<\/code><br \/>\n&nbsp;<br \/>\n<strong>Observa\u021bii<\/strong><\/p>\n<ol>In <strong>GSM<\/strong>, semnalul este demodulat GMSK \u0219i vocea reconstruit\u0103 prin codec AMR.<\/ol>\n<ol>In <strong>UMTS<\/strong>, demodularea este WCDMA (QPSK), vocea tot prin AMR.<\/ol>\n<ol>In <strong>LTE\/5G<\/strong>, vocea este transmis\u0103 ca VoIP (VoLTE\/VoNR), deci fluxul de date trece prin stack-ul IP \u00eenainte de a ajunge la codec-ul audio.<\/ol>\n<p>&nbsp;<\/p>\n<p>Pe scurt, principiul de func\u021bionare poate fi rezumat astfel:<\/p>\n<ul>\n<li>Pentru transmitere (TX): Re\u021belele digitale genereaz\u0103 date care sunt modulate digital. Aceste date sunt apoi convertite \u00een semnale analogice, care, prin etape succesive de filtrare \u0219i amplificare, sunt up-convertite la frecven\u021ba RF \u0219i apoi transmise c\u0103tre anten\u0103.<\/li>\n<\/ul>\n<ul>\n<li>Pentru recep\u021bie (RX): Semnalul RF captat de anten\u0103 este mai \u00eent\u00e2i amplificat (prin LNA), apoi convertit la o frecven\u021b\u0103 intermediar\u0103 (IF) prin down-conversion. Ulterior, semnalul este filtrat, amplificat \u00een etapa IF, convertit in semnal digital \u0219i procesat de unit\u0103\u021bile digitale pentru a reconstitui informa\u021bia ini\u021bial\u0103.<\/li>\n<\/ul>\n<p>&nbsp;<br \/>\n<strong>Concluzie<\/strong><\/p>\n<p>Pl\u0103cile radio Ericsson se remarc\u0103 prin performan\u021ba ridicat\u0103, fiabilitatea \u0219i capacitatea de a gestiona multiple standarde de comunica\u021bie mobil\u0103 prin arhitecturi sofisticate, care combin\u0103 func\u021bionalit\u0103\u021bi RF de precizie cu procesare digital\u0103 avansat\u0103. De\u0219i schematica exact\u0103 poate varia \u00een func\u0163ie de genera\u021bia de tehnologie \u0219i produs, schema bloc de mai sus surprinde \u00een linii mari convergen\u0163a \u00eentre conversia de frecven\u021b\u0103, amplificare, filtrare \u0219i procesare digital\u0103 necesare pentru a asigura comunica\u021bii mobile de \u00eenalt\u0103 calitate.<\/p>\n<p>Aceast\u0103 descriere ofer\u0103 o viziune de ansamblu asupra modului \u00een care func\u021bioneaz\u0103, \u00een principiu, pl\u0103cile radio Ericsson folosite \u00een telefonia mobil\u0103. \u00cen cazul unor detalii tehnice suplimentare sau implement\u0103ri specifice, se pot consulta documenta\u021bii tehnice specializate sau brevetele publicate de Ericsson, \u021bin\u00e2nd cont c\u0103 unele informa\u021bii pot fi confiden\u021biale.<\/p>\n<p><!-- Start of StatCounter Code --><br \/>\n<script type=\"text\/javascript\">\nvar sc_project=5241295; \nvar sc_invisible=1; \nvar sc_security=\"f184e0a9\"; \n    <\/script><br \/>\n<script type=\"text\/javascript\" src=\"http:\/\/www.statcounter.com\/counter\/counter.js\"><\/script><br \/>\n<noscript><br \/>\n<\/noscript><\/p>\n<p><noscript><\/p>\n<div class=\"statcounter\">\n<div align=\"center\"><a title=\"weebly reliable statistics\" href=\"http:\/\/www.statcounter.com\/weebly\/\" target=\"_blank\"><img decoding=\"async\" class=\"statcounter\" src=\"http:\/\/c.statcounter.com\/5241295\/0\/f184e0a9\/1\/\" alt=\"weebly reliable statistics\" ><\/a><\/div>\n<\/div>\n<p><\/noscript><\/p>\n<div align=\"center\"><!-- End of StatCounter Code --><\/div>\n","protected":false},"excerpt":{"rendered":"<p>&nbsp; De\u0219i detaliile specifice ale arhitecturii interne ale pl\u0103cilor radio Ericsson sunt protejate de secrete comerciale \u0219i pot varia de la o genera\u021bie la alta (de exemplu, \u00eentre sistemele GSM, UMTS, LTE sau 5G), se poate face o descriere general\u0103 a modului \u00een care func\u021bioneaz\u0103 aceste module \u00een contextul sta\u021biilor de baz\u0103 \u00een telefonia mobil\u0103. [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-708","post","type-post","status-publish","format-standard","hentry","category-electronica"],"_links":{"self":[{"href":"https:\/\/eugo.ro\/index.php?rest_route=\/wp\/v2\/posts\/708","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/eugo.ro\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/eugo.ro\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/eugo.ro\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/eugo.ro\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=708"}],"version-history":[{"count":61,"href":"https:\/\/eugo.ro\/index.php?rest_route=\/wp\/v2\/posts\/708\/revisions"}],"predecessor-version":[{"id":769,"href":"https:\/\/eugo.ro\/index.php?rest_route=\/wp\/v2\/posts\/708\/revisions\/769"}],"wp:attachment":[{"href":"https:\/\/eugo.ro\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=708"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/eugo.ro\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=708"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/eugo.ro\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=708"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}