টেলিযোগাযোগ ব্যবস্থা 


প্রশ্নোত্তরের মাধ্যমে টেলিযোগাযোগ ব্যবস্থা শিখি

Communication ej‡Z wK eySvq ?
DIi t `yÕwU (`~ieZ©x) ¯’v‡bi g‡a¨ ‡hvMv‡hvM‡KB Communication e‡j|

 Communication Network ej‡Z wK eySvq ?

DIi t †h †bUIqv‡K©i gva¨‡g `yÕwU (`~ieZ©x) ¯’v‡bi g‡a¨ †hvMv‡hvM ¯’vcb Kiv nq Zv‡K Communication Network e‡j|

 Communication Gi Rb¨ cÖavbZ wK †cÖvqRb ?

DIi t Communication Gi Rb¨ †h mKj DcKiY cÖ‡qvRb Zv n‡jv t-

• Transmitter
• Channel
• Receiver

wewfbœ channel Gi bvg ¸‡jv nj t-

1. Open wire channel (Electrical signal)
2. Twisted pare (Electrical signal )
3. Pare ware (Electrical signal)
4. Co-axial cable (Electrical signal)
5. Optical fiber (Optical signal)
6. Radio Frequency (RF) Channel (Electromagnetic signal)

 wmMbvj ej‡Z wK eySvq ?

DIi t mg‡qi mv‡_ cwieZ©bkxj, ˆe`y¨wZK , Optical ev Electromagnetic ivwk hv †Kvb Z_¨/ A_© enb K‡i Z‡K wmMbvj e‡j|

 wmMbvj Gi mvaviY aiY ¸‡jv D‡j­L Ki|

DIi t wmMbvj mvaviYZ wZb ai‡bi nq †m¸‡jv n‡jv t-

1. Electrical signal
2. Electromagnetic signal
3. Optical signal

 Antenna ej‡Z wK eySvq ?

DIi t †h avZe `Û B‡jKwUªKvj wmMbvj †K Electromagnetic signal ev Electromagnetic signal †K B‡jKwUªKvj wmMbvj G  রুপান্তর   K‡i Zv‡K Antenna e‡j| 

Noise ej‡Z wK eySvq?

&DIi t †h †Kvb ai‡bi AbvKvw•LZ wmMbvj †K Noise e‡j|

Frequency, Time period, Amplitude, Phase I Wave length ej‡Z wK eySvq?

DIi t

Amplitude t wmMbv‡ji mvg¨Ae¯’vb †_‡K †h ‡Kvb GK w`‡Ki m‡e©v”P `~iZ¡‡KB Amplitude e‡j|

Time Period t wmMbv‡ji GKwU c~Y© mvB‡Kj m¤úY© Ki‡Z †h mgq jv‡M Z‡K UvBg wcwiIW e‡j|

Frequency t ‡Kvb wmMbvj GKK mg‡q hZ¸‡jv c~Y© mvB‡Kj m¤úY©  K‡i Zvi msL¨v‡K Zvi Frequency e‡j|

Phase t †Kvb wmMbv‡ji †idv‡iÝ we›`yi mv‡c‡¶ Zvi Ae¯’vb‡K Phase e‡j|

Wave length t ‡Kvb wmMbvj GKwU c~Y© mvB‡Kj m¤úY© Ki‡Z †h mgq jv‡M †m mg‡q †h `~iZ¡ AwZµg K‡i Zv‡K Zvi Wave length e‡j| G‡K Lamda (λ) Øviv cÖKvk Kiv nq|

Audio, Video Ges Voice signal Gi Frequency range KZ?

DIi t

Audio signal Gi Frequency range  = 20 Hz – 20,000 Hz

Frequency, Wave length I Velocity Gi ga¨Kvi m¤úK© wjL |

DIi t Frequency, Wave length I Velocity Gi ga¨Kvi m¤úK nj t Ñ

          V = fλ

 GLv‡b ,

          V = Velocity ev †eM

          λ = Wave length  ev Zi½ ˆ`N©

GKwU Antenna Gi Effective radiation Gi Rb¨ Gi ˆ`N©¨ †Kgb nIqv DwPZ?

DIi t GKwU Antenna Gi Effective radiation Gi Rb¨ Gi ˆ`N©¨ mvaviYZ λ/2 ev λ/4 nIqv DwPZ

Modulation ej‡Z wK eySvq?

DIi t Information signal Gi ˆewkó Abyhvqx Carrier signal Gi ˆewk‡ói cwieZ©b †K Modulation  e‡j|

Amplitude Modulation ej‡Z wK eySvq?

DIi t †h Modulation system G information signal Gi Amplitude (Intensity)Abyhvqx Carrier signal Gi Amplitude cwieZ©b nq Zv‡K Amplitude Modulation e‡j|

Frequency Modulation ej‡Z wK eySvq?

DIi t †h Modulation system G information signal Gi Amplitude (Intensity) Abyhvqx Carrier signal Gi Frequency cwieZ©b nq Zv‡K Frequency  Modulation e‡j|

Phase Modulation ej‡Z wK eySvq?

DIi t †h Modulation system G information signal Gi Amplitude (Intensity) Abyhvqx Carrier signal Gi Phase  cwieZ©b nq Zv‡K Phase  Modulation e‡j|

Channel capacity ej‡Z wK eySvq?

DIi t ‡Kvb P¨v‡bj GKK mg‡q m‡e©v”P †h cwigvb weU UªvÝwgU Ki‡Z cv‡i Zv‡K Channel capacity e‡j|

Band width ej‡Z wK eySvq?

DIi t †Kvb P¨v‡bj w`‡q †h wmMbvj UªvÝwgU ev wiwmf Kiv nq Zvi D×mxgv n‡Z wbgœ mxgvi cv_©K¨‡K Band width e‡j|

 i.e.  B = f_h – f_L

Frequency spectrum ej‡Z wK eySvq?

DIi t Time domain signal  ‡K frequency domain sign রুপান্তর Ki‡j Graphical ‡h wPG cvIqv hvq Zv‡K Frequency Spectrum e‡j|

Amplitude Modulated Gi sideband ¸‡jv   Ki?

DIi t  

i ) Upper side band , (f_c + f_m )

ii) Lower side band , (f_c – f_m )

Satellite ej‡Z wK eySvq?

DIi t Satellite Gi ai‡bi wiwcUvi hv f~ -c„ó †_‡K cÖvq 36000 wK‡jvwgUvi Dc‡i KZ¸‡jv Abyমোw`Z e„IKvi ev Dce„Kvi c‡_ AveZ©bKvix Communicating device hv earth station Gi uplink frequency (6 GHz) receive K‡i cÖ‡qvRbxq cÖ‡mwms †k‡l downlink frequency (4 GHz) G তেdestination earth station Gi D‡Ï‡k transmit K‡i `xN© `~i‡Z¡i reliable communication m¤úY© Ki‡Z ব্যবহৃত nq|

K‡qKwU pulse Modulation Gi bvg wjL?

DIi t

        i.            Pulse Amplitude Modulation (PAM)

      ii.            Pulse Width Modulation (PAM)

    iii.            Pulse Position Modulation(PPM)

   iv.            Pulse Duration Modulation (PDM)

Optical Fiber ej‡Z wK eySvq?

DIi t Optical fiber GK ai‡bi bgbxq KuvP ev c­vw÷‡Ki Zš‘ hv Core (Av‡jvK enb K‡i), Cladding (Av‡jvi cÖwZdjb K‡i) Ges Jacketing/Coating  (hv AvNvZ ev Av`ªZv †_‡K i¶v K‡i) wb‡q MwVZ GK ai‡bi Av‡jvK evnxbj| 

Optical fiber Gi myweav Ges Amyweav ¸‡jv wjL |

DIi t

myweav mg~n t

1.      Ab¨vb K¨vej Gi Zyjbvq Gi Attenuation Kg |

2.     AvK‡i †QvU Ges nvjKv |

3.     Interference ‡bB ej‡jB P‡j|

4.     Long lifetime

5.     Large bandwidth

6.     Data rate ‡ewk |

7.     Per channel cost Kg|

8.     KuvPv gv‡ji `vg Kg |

9.     i¶bv‡e¶b mnR|

10. Kg wiwcUvi jv‡M |

Amyweav mg~n t

1.      ms‡hvM LiP Lye †ewk |

2.     Scattering N‡U

3.     Absorption N‡U |

4.     wmMbvj †cÖvcv‡Mkb G kw³ Lye †ewk K‡g hvq|

 ASK, FSK, PSK ej‡Z wK eySvq?

DIi t

AKK(Amplitude shift keying) tÑ †h system G Digital information signal Gi amplitude Avbyhvqx Analog carrier signal Gi amplitude Gi cwieZ©b nq Zv‡K ASK e‡j|

FSK (Frequency shift keying) t Ñ †h system G Digital information signal Gi amplitude Avbyhvqx Analog carrier signal Gi frequency Gi cwieZ©b nq Zv‡K FSK e‡j|

PSK (Phase shift keying) tÑ †h system G Digital information signal Gi amplitude Avbyhvqx Analog carrier signal Gi Phase Gi cwieZ©b nq Zv‡K PSK e‡j|

Time Division Multiplexer ej‡Z wK eySvq?

DIi t TDM t ‡h wm‡÷‡g GKvwaK BbcyU wmMbvj †K GKwU gvG wmMbvj UvBg wkqvwis Gi gva¨‡g Zv‡`i ci¯ú‡ii interface QvovB serial o/p cÖ`vb K‡i Zv‡K Time Division Multiplexer e‡j|

Multiplexing Gi e¨venvi Ges cÖ‡qvM‡¶G ¸‡jvi bvg wjL|

DIi t Multiplexing Gi e¨venvi Ges cÖ‡qvM‡¶G ¸‡jvi bvg nj t -

1.      Long Haul communication

2.     Fiber optic communication

3.     High speed Data communication

4.     Satellite commutation

5.     Network Connection

6.     Transport Connection

GKwU Supper heterodyne Radio Receiver Gi e­K WvqvMÖvg mn Kvh©cÖYvjx eYbv Ki |

DIi t   

Radio Receiver t †h Communication device Rf signal ‡K (550KHz – 1650 KHz ev 88MHz- 108 MHz) wiwmf K‡i Zv‡K mvaviYZ †iwWI wiwmfvi e‡j|

wPG t

eY©bv t

i)                   Rf signal t Antenna electromagnetic Rf signal  †K Rf electrical signal G i“cvš—i K‡i|

ii)                 Rf Amp t hv ïaygvG Rf signal †KB Amplify K‡i|

iii)               local oscillator t ‡iwoI wiwmfvi Gi †jvKvj Awm‡jUi me©`v Rf signal ‡_‡K †ewk gv‡bi Frequency Drcbœ K‡i| Rf Ges †jvKvj wd«Kz‡qwÝ Gi cv_©K¨ mvaviYZ 455KHz nq|

iv)               Mixer t Bnv Rf I †jvKvj Awm‡jUi Gi wd«Kz‡qwÝ Gi g‡a¨ cv_©K¨ wbY©q K‡i i/p ‡`q|

v)                 IF Amp t Intermediate Frequency Amplifier ïaygvG Rf wmMbvj‡KB ewa©Z K‡i|

vi)               Detector t Detector ckt Modulated inventor Gi †h †Kvb GKwU †K DetectorK‡i|

vii)             AF Amp t Audio Frequency Amplifier ïaygvG Rf Gi AwWI wmMbvj‡K Amplify K‡i|

viii)           Lode Speaker t Lode Speaker electrical audio signal †K Mechanical Audio signal G i“cvš—i K‡i|

Telegraph ckt mvaviYZ KZ cÖKvi I wK wK ?

DIi t  Telegraph ckt mvaviYZ 4 cÖKvi h_v t

i)                   Simplex (sx)

ii)                 Half  Duplex (HDx)

iii)               Full Duplex (FDXx)

iv)               Full/Full duplex

Telegraph ckt Gi mw¶ß eY©bv `vI।

DIi t Simplex t †h KwgDwb‡Kkb mvwK©‡U ïaygvG GKB w`K †_‡K Z_¨ cvVv‡bv hvq, wKš‘ KLbB Aci cÖš— n‡Z cvQv‡bv hvq bv Zv‡K Simplex wm‡÷g e‡j| ‡hgg t †iwoI।

Half  Duplex t †h KwgDwb‡Kkb wm‡÷‡g Z_¨ †K ïaygvG GKB mg‡q GKw`K †_‡K cvVv‡bv hvq| A_©vr cÖ_g cÖvš— hLb UªvÝwgU nq ZLb 2q cÖvš— ZLb wiwmfvi | Avevi 2q cÖvš— Tx nq ZLb cÖ_g cÖvš— Rx | ‡mB KwgDwb‡Kkb wm‡÷g †K Half  Duplex wm‡÷g e‡j|

Duplex t †h KwgDwb‡gkb wm‡÷‡g GKB mg‡q Dfq w`K †_‡K Z_¨ Tx ও  Rx Kiv hvq Zv‡K Duplex   wm‡÷g e‡j| †hgb t †Uwj‡dvb, †gvevBj |

Full/Full duplex t †h KwgDwb‡Kkb wm‡÷‡g GKB mg‡q `yB‡qi AwaK MÖvnK GKB mg‡q wb‡R‡`i g‡a¨  Z_¨ Transmit ও Receive   Ki‡Z cv‡i Zv‡K Full/Full duplex wm‡÷g e‡j| ‡hgb t †UwjKbdv‡iÝ , wfwWI Kbdv‡iÝ BZ¨vw`

Communication receiver ej‡Z wK eySvq?

DIi t ‡h Receiver transmitted shortwave signal receive G LyeB cvi`kx Ges hv we‡bv`bgyjK Kv‡R e¨envwiZ bv n‡q wewfb ai‡Yi †hvMv‡hvM Kv‡R e¨venvwiZ nq Zv‡K Communication receiver e‡j| ‡hgb t ‡gvevBj , ‡Uwj‡dvb BZ¨vw` |

Communication Rx Gi e­K WvqvMÖvg mn Kvh©cÖYvjx eY©bv Ki|

DIi t

Kvh©cÖYvjx t

Ø     Antenna – Electromagnetic Rf signal (2 -110 MHz) ‡K B‡jKwUªKvj wmMbv‡j i“cvš—i K‡i|

Ø     Antenna Coupling unit – Bnv GKwU B‡jKwUªK mvwK©U hv Rf GbwUbv †K g~j wiwmfv‡ii Tuning ckt Gi mv‡_ mshy³ K‡i|

Ø     Rf Amp – Rf electrical signal ( 2 -16 mHz ) ‡KB ïay gvG ewa©Z K‡i| G‡Z GKwU e¨vÛ cvm wdëvi _v‡K|

Ø     1^st Mixer – Bnv †jvKvj Awm‡jUi (3.7 - 17.7 †gMvnvh© ) wd«Kz‡qÝx †_‡K Rf (2 – 16 MHz) frequency Gi cv_©K¨ †K cieZ©x †÷‡R †cÖiY K‡i|

Ø     1^st stage IF Amp – ïaygvG First frequency signal ‡KB ewa©Z K‡i | GLv‡b GKwU e¨vÛ cvm e¨venvwiZ nq|

Ø     Local oscillator – Bnv GKwU nvB wd«Kz‡qwÝ Awm‡jUi mvwK©U hv wbw`ó gv‡bi wd«Kz‡qwÝ Drcbœ K‡i| g~jZ G‡¶‡G demodulation Gi Rb¨ mnvqK wnmv‡e e¨envi Kiv nq|

Ø     2^nd mixer – Bnv wg¯‹vi mvwK©U If signal (1.7MHz) and local oscillator (1.5MHz) Gi wd«Kz‡qwÝ Gi cv_©K¨ †K cieZ©x †÷‡R cvVvq |

Ø     2^nd If Amp – ïaygvG if frequency (200KHz) †K ewa©Z K‡i| GLv‡b GKwU low pass filter e¨evni Kiv nq|

Ø     Beat frequency :oscillator – Beat Drcv`‡bi GB Awm‡jUi GKwU nvB wd«Kz‡qwÝ Drcv`b K‡i|

Ø     AGC Amp – Bnv mvwK©U Gi †MBb †K K‡›Uªvj Kivi Rb¨ Automatic gain control e¨venvwiZ nq|

Ø     AGC Detector – Gain KZUyKy n‡e Zv wbY©q K‡i|

Ø     Squcleh ckt – wiwmfvi Gi I/P bv _vK‡j Amplify ckt †K  eÜ iv‡L|

Ø     Audio Amp – Audio Frequency ‡KB  ïaygvG ewa©Z K‡i| GLv‡b GKwU low pass Filter e¨venvwZ nq|

Ø     Detector – GB wW‡UKUi mvwK©U G Demodulation Process †K  m¤úY© K‡i| Ges gWy‡jkb I‡qf †_‡K K¨vwiqvi †K cy‡ivcywwi Avjv`v K‡i|

Ø     Power Amp- High power band speaker ‡K WªvBf Kivi Rb¨ IwWq wd«Ky‡qw݇K cÖ‡qvRbxq gv‡b ewa©Z K‡i|

Ø     Lode speaker – Bnv GK ai‡bi Mechanical transducer hv B‡jKwUªKvj wmMbvj †K g¨vM‡bwUK wmMbvj G i“cvš—i K‡i|

Communication receiver (Rx) Gi sensitivity ej‡Z wK eySvq|

DIi t GKwU wiwmfvi KZ `ye©j Rf signal receive K‡i Zv ewa©Z K‡i Bbdi‡gkb ev gWy‡jwUs wmMbvj †K wiKfvwi Ki‡Z cv‡i Zv‡K Zvi   sensitivity e‡j|

Communication Receiver Gi Selectivity ej‡Z wK ey~Svq|

DIi t GKwU wiwmfvi Gi mKj unwanted signal †K  ev` w`‡q ïaygvG wanted signal ‡K wiwmf Kivi ¶gZv †K KwgDwb‡Kkb Rx Gi selectivity e‡j|

Communication receiver Gi Fidelity ej‡Z wK eySvq|

DIi t †Kvb KwgDwb‡Kkb Rx GKwU `ye©j wmMbvj MÖnb K‡i h_vµ‡g Amplify , selection, Filtering K‡i †Kvbv cªKvi Distortion QvoB KZUv wbLyZ fv‡e Bbdi‡gkb †K o/p G cvVv‡Z cv‡i Zv‡K Gi fidelity e‡j|     

 ‡jv †j‡fj Ges nvB ‡j‡fj gWy‡jkb Gi ga¨ Kvi cv_©K¨ D‡j­L Ki?

DIi t

Low level Modulation	High level Modulation
1. low level Modulation Gi o/p cvIqvi Kg |	1. nvB †j‡fj gWy‡jkb Gi o/p power ‡ewk|
2. Gi †MBb Kg	2. Gi †MBb †ewk|
3. Gi `¶Zv Kg |	3. Gi `¶Zv †ewk |
4. Final power Amp Gi c~‡e© gWy‡jkb cvIqvi hvq|	4. Final power Amp Gi gWy‡jkb m¤úY© nq|

†iwWI wiwmfvi ev UªvÝwgUvi Gi †kªYxwefvM Ki|

DIi t †iwWI wiwmfvi ev UªvÝwgUvi cÖavZ 4 cÖKvi h_v t

1.      cvIqvi Gi Dci wfwI K‡i|

2.     wd«Ky‡qwÝ Gi Dci wfwI K‡i|

3.     gWy‡jkb Gi Dci wfwI K‡i|

4.     Kv‡Ri Dci wfwI K‡i|

* cvIqv‡ii Dci wfwI K‡i wZb cÖKvi

1.      nvB cvIqvi wiwmfvi /UªvÝwgUvi

2.     ‡jv cvIqvi wiwmfvi / UªvÝwgUvi

3.     gWy‡jkb cvIqvi wiwmfvi / UªvÝ wgUvi

* wd«Ky‡qwÝ Gi Dci wfwI K‡i 5 cÖKvi

1.      Short wave Tx/Rx

2.     Mediam wave Tx/Rx

3.     Long wave Tx/Rx

4.     VHF and VHF Tx/Rx

5.     Micro Wave Tx/Rx

*Modulation Gi Dci wfwI K‡i wZb cÖKvi

1.      Amplitude Modulation Tx/Rx

2.     Frequency Modulation Tx/Rx

3.     Phase Modulation Tx/Rx

* Kv‡Ri Dci wfwI K‡i 5 cÖKvi

1.      Radio broad cast Tx/Rx

2.     Radio Telephone Tx

3.     Radio Telegraphy Tx

4.     Radder Tx

5.     Navigation Tx

Channel capacity wK wK welq Gi Dci wbf©i K‡i?

DIi t

1.      Bandwidth Gi Dci ;

2.     Receiver signal power Gi Dci ;

3.     Noise Power Gi Dci ;

SNR ej‡Z wK eySvq? Gi gvb Kg bv ‡ewk nIqv fvj |

DIi t

SNR – signal to noise ratio . ‡Kvb wmMbvj Gi cvIqvi Ges b‡qm cvIqvi Gi Ab~cvZ †K signal to noise ratio e‡j| SNR Gi gvb †ewk nIqv fvj |

Noise Figure ej‡Z wK eySvq?

DIi  t ‡Kvb wm‡÷‡gi BbcyU SNR and out put SNR Gi AbycvZ †K Noise Figure e‡j|

Channel capacity Gi m~G mg~n D‡j­L Ki|

DIi t

Noise lass channel Gi Rb¨ Channel capacity C ev R = 2Blog₂²

GLv‡b , C ev R = Channel capacity

          B = Channel Gi Band width

          L= Level Gi ms½v

Noise channel Gi Rb¨

Channel Harthy  Gi g‡Z Channel capacity

          c= B log₂ (1 + SNR)

          C= Blog₂ (1 + S/N)

GLv‡b , C= Channel capacity

           B= Band width

           SNR = signal to noise ratio

Noise wK? Gi †kªYx wefvM †`LvI।

DIi t Noise - †h  †Kvb ai‡bi AbvKvw•LZ wmMbvj †KB b‡qm e‡j|

Noise cÖavbZ 2 cÖKvi

1.      Internal Noise

2.     External Noise

Internal noise 7 cÖKvi

1.     Thermal noise

2.     Shat Noise

3.     Flicker Noise

4.     Transitive Noise

5.     Partition Noise

6.     Crass talk Noise

7.     In pulse Noise

External Noise 2 cÖKvi

1.     Atmospheric Noise

2.     Non-made Noise

Telecommunication Gi †¶G mg~n wjL|

DIi t

1.     Telegraph

2.     Telephone

3.     Television

4.     Radio

5.     Vision Phone

6.     Cellular Phone

7.     RADAR

8.     Navigation

9.     Satellite Communication

10. Optical Fiber Communication

wWwRUvj KwgDwb‡Kkb wm‡÷‡gi myweav mg~n wjL|

DIi t

1.      G‡Z Z‡_¨i †MvcbxqZv i¶v Kiv m¤¢e

2.     Z_¨ m~¶fv‡e UªvÝwgU Kiv m¤¢ve|

3.     wewfbœ wm‡÷g Gi mgš^q Kiv m¤¢e

4.     AwZ mn‡R WvUv †÷vi Kiv m¤¢e

5.     e¨ewnZ IC mg~n mnR jf¨

6.     A‡Uv‡gwUK Acv‡ikb m¤¢e

WWW Gi c~Y© A_© wK?

DIi t WWW – World Wide Web

Internet wK?

DIi t †bUIqvK© mg~‡ni †bUIqvK©†K B›Uv‡bU e‡j| mvaviYZ Kw¤úDUvi/মোবাইল †_‡K Kw¤úDUvi/মোবাইল

FAX ej‡Z wK eySvq?

DIi t

FAX (Facsimile) A_© AweKj c~YরDrcv`b ev exactly reproduction . FAX machine Øviv KvM‡Ri Dci wjwLZ msev` ev B‡gR †K maviYZ †Uwj‡dvj jvB‡bi gva¨‡g ev †iwWI Acv‡ikb Gi gva¨‡g Ab¨ FAX (Facsimile) ‹ G †cÖiY Kiv hvq|

VSAT ej‡Z wK eySvq?

DIi tVSAT Gi c~Y© A_© nj Very small Aperture tenminal . VSAT nj Lye †QvU AvK‡ii ms‡hvM hš¿ hv wØ-gyLx Av_© †÷kb wnmv‡e KvR K‡i| Gi gvjv AvK„wZi GbwUbvi e¨vm I wgUvi Kg nq, †hLv‡b Ab¨vb¨ ai‡bi Av_© †÷kb Gi GmwUbvi e¨vm 10m Gi gZ nq| VSAT  me‡P‡q †ewk e¨envwiZ nq weµq †K‡›`ª †µwWW KvW© msµvš— †jb‡`b Gi LiP Kg| wewfbœ gWy‡jkb I gvwë‡c­¯‹ A¨v‡mm e¨evni K‡i K‡›Uªvj ‡nv÷ Kw¤úDUvi †_‡K A‡bK †ewk msL¨K `~ieZ©x ¯’v‡b WvUv Av`vb cÖ`vb Kiv nq|

Cellelar radio Telephone system Gi D‡j­L‡hvM¨ Ask¸‡jvi bvg wjL?

DIi t

1.      A‡bK Call site

2.     Control switching system

3.     cÖwZwU Call site Gi GKwU Controllers

4.     Switching system Gi GKwU Centrall controller 

Mobile Communication Gi e¨envi wjL।

DIi t  

        i.            Music, News, Weather, Road Traffic conditon BZ¨vw` Lei †kvbvi Rb¨ hvbevn‡b †gvevBj KwgDwb‡Kkb e¨evnwZ nq|

      ii.            Emaergency t Hospital Gi ambulance, Fire brigade, police control room BZ¨vw`i mv‡_ †hvMv‡hvM, Wyeš— RvnvR nVvr weKj nIqv aerplane Gi pilot mvnv‡h¨ †gvevBj KwgDwb‡Kkb Gi mvnh¨ †bq|

    iii.            ågvb we‡µZv nVvr †Kvb c‡b¨i e¨cv‡i cb¨ Drcv`b Kvix cÖwZóv‡bi mv‡_ Ri“jx †hvMv‡hv‡M †gvevBj KwgDwb‡Kkb e¨envwiZ nq|

   iv.            Lye `~ieZ©x ¯’v‡bi mv‡_ Zvi †hvMv‡hvM A‡bK mgq m¤¢e nq bv ZLb Zv‡ii cwie‡Z© †gvevBj KwgDwb‡gkb e¨envwiZ nq|

     v.            ‡h †Kvb `yBU ¯’v‡bi g‡a¨ Z_¨ Av`vb cÖ`vb Ki‡Z e¨venvi nq|

†gvevBj KwgDwb‡Kkb G e¨envwiZ wWfvBm ¸‡jvi bvg wjL।

DIi t

        i.            Sencor

      ii.            Pager

    iii.            Personal digital Antenna

   iv.            Note Book Laotop

     v.            Embeded Controller

   vi.            Mobile Phone

†gvevBj KwgDwb‡Kk‡b e¨envwiZ wd«Ky‡qwÝ e¨vÛ ¸‡jv D‡j­L Ki|

DIi t

1.     MTs (Mobile Telephone services) : 35 MHz – 45 MHz

2.     IMTS (Improved Mobile Telephone Services ) : 150 MHz- 450MHz

3.     AMPS (Advance Mobile Telephone services) : 825 MHz- 890 MHz

4.     DAMPS (Digital Advance m.p services) 1850MHz – 1990 MHz

‡gvevBj KwgDwb‡Kkb Gi †jqvi ¸‡jv eY©bv Ki|

DIi t

‡gvevBj KwgDwb‡Kkb Gi †jqvi ¸‡jvi bvg nj t

1.      Physical layers

2.     Data link layers

3.     Network layers

4.     Application layers

5.     Transport layers

Physical layers : Wireless communication Gi WvUv ¸‡jv wdwRK¨vj †jqvi G weU AvK‡i _v‡K | ‡gvevBj KwgDwb‡Kkb G wdwRK¨vj †jqvi wU Frequency selection, carrier Frequency, signal detection Ges K¨vwiqvi wd«Ky‡qwÝi mv‡_ Bbdi‡gkY wmMbvj Gi gWy‡jkY K‡i|

Data link layers : ‡hvMv‡hvM gva¨‡gi mv‡_ †hvMv‡hvM ¯’vcb Kiv Multiplexing – demultiplexing Kiv , Point to point  I Point to multipoint  †hvMv‡hvM Kiv |

Network layers : Intermadiate system mg~‡ni g‡a¨ †hvMv‡hvM ¯’vc‡bi Rb¨ Addressing roreting Device location Ges `yBwU †bUIqvK© Gi g‡a¨ n¨vÛ Ad ¯’vcb K‡i|

Transport layers : End to End ms‡hv‡Mi g~j †idv‡iÝ gWy‡jU wnmv‡e e¨envwiZ n‡q QOS Signal flow ,congestion control K‡i|

Application layers : mKj Brod casting GB †jqviGi Øviv m¤úvw`Z nq|

¶z`ª Cell wewkó Cellular Gi myweav Ges Amyweav mg~n †jL?

DIi t

myweav mg~n t

1.      Higher channel capacity

2.     less transmission power

3.     Local interface Lye Kg |

4.     Robustness Lye †ewk |

5.     wmMbvj bv cIqvi m¤¢ebv Kg |

Amyweav mg~n t

1.      e¨vq eûj

2.     n¨vÛ Ad Gi cª‡qvRb nq|

Cellular Phone G e¨venvwZ AvBwm mg~‡ni mvaviY GKwU ZvwjKv †jL|

DIi t

1.     PCB 80/83 c555 : Microcontrolar

2.     VAM 1000 ;Data Process

3.     NE/SA 650 : Mixer, oscillator and FMIM system

4.     TDO 1742 : Tranceiver Frequency

 Blocked Frequency Kx?

DIi t cÖwZwU e¨venviKvwii Rb¨ GKwU wbw`ó wd«Kz‡qwÝ eiv× _v‡K GB wbw`wó wd«Kz‡qwÝB nj †e­v‡KW wd«Ky‡qwÝ |

Satellite Earth station ej‡Z wK eySvq|

DIi t ‡h KwgDwb‡Kkb wWfvB mg~n mvaviYZ f~-c„ó Gi Dci A¯’vb K‡i †mUvjvBU mg~‡ni mv‡_ I wewfbœ terrestrial network Gi mv‡_ †hvMv‡hvM i¶v K‡i Zv‡`i †K Av_© †÷kb e‡j|

Av_© †÷kb Gi e­K WvqvMÖvg mn Kvh©cÖYvjx eY©bv Ki|

DIi t

Kvh©cYvjx t

1. U-Wave antenna – Satellite Gi Downlink frequency   †K B‡jKwUªK wmMvbv‡j i“cvš—i K‡i|

2. BPL – ïaygvG WvBbwjK e¨vÛ †K cvm K‡i|

3. LNA – Low noise Amplifier GB wmMbvj wU Ggb fv‡e wmMbvj †K ewa©Z K‡i †h wmMbvj ewa©Z n‡e wKš‘ b‡qm ewa©Z †mB Zzjbvq Kg  n‡e|

4. Mixer ; Awm‡jUi wdªKz‡qwÝ Ges wiwfvi wd«Kz‡qwÝ Gi ga¨Kvi c‡qvRb cÖwµqv IF signal ‰Zwi K‡i|

5. Modulator : gyj wmMvbv‡ji mv‡_ K¨vwiqvi wmMbvj †K super impoZ Kiv nq|

6 . Demodulator : gWy‡j‡UW wmMbvj †_‡K K¨vwiqvi wmMbvj ev` w`‡q g~j wmMbvj †K Avjv`v K‡i|

7. HPA : ‡h‡nZz m¨vUvjvBU f~-c„ó n‡Z A‡bK D”P Zvq Aew¯’Z Zvq wmMbvj †K A‡bK `~iZ¡ cÖcv‡MU Ki‡Z n‡e| GB Rb¨ wmMbvj †K nvB cvIqvi Amplifier Øvi ewa©Z K‡i Av_© †÷k‡b UªvÝ wgU K‡i †ciY Kiv nq|

GSM System Gi wPG AsKb K‡i ms‡¶‡c Kvh©cÖYvjx eY©bv

DIi t

eY©bv t Ms station hLb called party †K dile K‡i ZLb Zv cÖ_‡g BTS Gi mv‡_ SS7 m¤úY© K‡i| BTS hLb †`‡L called party †mB BTS GB Av‡Q ZLb Zvi mv‡_ BTS GKwU †hvMv‡hvM ¯’vc‡bi Rb¨ SS7 signaling initiate K‡i| wKš‘ hw` celled Party H BTS G bv _v‡K Zvn‡j BTS Zvi BSC Gi K‡Q Called party  †LvRvi ØwqZ¡ fvi Ac©b K‡i| BSC Gi Kv‡Q bv _vK‡j MSC Gi Kv‡Q ØwqZ¡ fvi AcY© K‡i| ON –net call Gi Rb¨ Kj c¨v‡ivwU †K MSC Gi VLR I HLR Gi mvn‡h¨ Ly‡R †mj Cstanlish Kiv nq| wKš‘ hw` Kj c¨v‡ivwU Ad †bU nq Z‡e Kj c¨v‡iwU Gi MSC †_‡K Ly‡R call cestablish Kiv nq| wKš‘ Kj bv¤^vi international n‡j IGF Gi mv‡_ SS7 m¤úY© K‡i| GKB fv‡e Kj c¨v‡ivwU Ly‡R Call establish Kiv nq|

Legend

MS – Mobile station

BTC- Base Transceiver Station

BSC – Base Station Controller

MSC – Mobile services Switching center

VIR – Equipment Identity Register

OMC – Operation & Maintenance controller

GMSC- Gateway Mobile switching center

AUC – Authentication Center

HTTP, HTML ,SMTP, UART, USART, IMAP, APN, DNS, E-Mail , SONET,RADAR, IMSI, TCP, FTP Gi c~Y© A_© wjL?

DIi t

HTTP – Hipper transmission protocol

HTML- Hipper text markup language

SMTP – Simple mail transfer protocol

UART- Universal synchronous receiver transmitter

IMAP – Inter Messing Access protocol

APN- Access point name

DNS – Domain name system

E-Mail – Electronic mail

SONET- synchronous poetical Network

NWD – Nation wide dialing

RADAR- Radio detection And ranged

IMSI- International mobile subscriber identity

TCP – Transmission control protocol

FTP – File Transfer Protocol

Geo stationary orbit Kx?

DIi t f~-c„ó ‡_‡K †h B”PZvh †÷kb Gi cªwZ c„w_exi AwfK‡l© ej Ges †mUvjvBU Gi †K‡›`ª wegyLx ej ci¯úi mgvb nq| †mB D”PZvq †h c‡_ cÖw_exi mv‡_ synchronous speed Gi †mUjvBU c„w_ex‡K cª`k©b K‡i Zv‡K Geo stationary orbit e‡j|

wWwRUvj KwgDwb‡Kkb Gi Amyweav mgyn †jL?

DIi t

1.      Smaller band width

2.     noise world Gi mv‡_ me©`v B›Uvi‡dwms RwVjZvi m¤§Lxb n‡Z nq|

3.     old tecnology Gi mv‡_ e¨envi Kivi Rb¨ AwaK instolotion cost e¨q Ki‡Z nq|

4.     P¨v‡bj K¨vcvwmwU mxwgZ |

5.     Efficiency transmission media Gi Dci wbf©ikxj

PDA Kx?

DIi t Personal dugital Assintant GKwU Advance Ges Mordan communicating hand terminal device hv †`L‡Z GKwU †gvevBj †dvb Gi gZ | Z‡e mvaviYZ gvB‡µvmdU Awdm ;out lock; exprecs; pdf;reaser;image ;ciewer; sftwaer lbultt in AvKv‡i ev BÝUj †hvM¨ nq|

ISDN Gi myweav mg~n D‡j­L Ki|

&DIi t

myweav mg~n t

1.      WvUv UªvÝwgU Gi LiP Kg|

2.     g‡Wg QvovB WvUv UªvÝwgU ev wiwmf Kiv hvq|

3.     wewfbœ wWwRvj ms‡hv‡M †`Iqv qvq |

4.     ‡UwjKbdv‡iÝ Lye fvj |

5.     G‡Z jvBb mvwP©s Gi e¨e¯’v Av‡Q |

6.     WvUv †iU Lye †ewk |

7.     Lye mn‡RB BbUvi‡bU Gi mv‡_ ms‡hvM Kiv hvq|

Double side band Gi `yBwU Amyweav †jL?

DIi t

1.      AwaK UªvÝwgkb cvIqvi Gi cª‡qvRb nq|

2.     AwaK e¨vÛ IqvBW Gi cª‡qvRb nq|

†mUvjvBU AiweU wK?

DIi t †mUvjvBU mg~n †h K¶c‡_ AveZ©b nq Zv‡K AiweU e‡j|

†mUvjvBU diUwcÖ›U wK?

DIi t †h AÂj Ry‡i †mUvjvBU Zvi †bUIqvK© Kfv‡iR _v‡K Zv‡KZvi dU© wcÖ›U e‡j|

cÖ‡UvKj wK?

DIi t `y‡Uv  wWfvB ci¯úi g‡a¨ †hvMv‡hvM ¯’vc‡bi Rb¨ KZ¸‡jv wbqg †g‡b P‡j| GB wbqg mg~n‡KB †cÖvUKj ejv nq| 

†bUIqvK© Gi eûj e¨evnvwiZ cÖ‡UvKj ¸‡jvi bvg wjL।

DIi t

        i.            TCP/TP (Transmission Control Protocol/Internet Protocol )

      ii.            IPX/SPX (Internet working packet Exchange / Sequence Packet Exchange)

    iii.            NET Beui – Net Bios. extended user interface

   iv.            FTP – File Transfer Protocol

     v.            HDLC- High Level Data Control 

Balanced Modulation ckt AsKb K‡i Gi Kvh©cÖYvjx eY©bv Ki।

DIi t 

Balanced Modulation GK cÖKvi wjwbqvi Amplitude Modulator hvi mvnv‡h¨ cÖ‡qvRb Abyhvqx Carrier Frequency †K ev` w`‡q Aewkó Ask‡K o/p G cÖ`vb Kiv hvq | GLv‡b Q<sub>1</sub> I Q<sub>2</sub>  Transistor Gi mvnv‡h¨ cykcyj Amplifier ckt mvwK©U ˆZwi Kiv nq| Balanced Modulation ckt e¨ve¯’vq GKwU †m›UviU¨vc UªvÝwgUvi T<sub>1</sub> Gi I/P G gWy‡jwUs wmMbvj cÖ`vb Kiv nq hv Dfq UªvÝwm÷i Gi †em G ‡cŠQvq G`‡i cÖK„ywZ GKB iKg nIqvq G‡`i †em G wecixZ Polarity wmMbvj Av‡m | Ges T₂ Transformer Gi mvn‡h¨ T₁ Gi †m›UviU¨vc K¨vwiqvi wmMbvj cÖ`vb K‡i| Dfq Transistor Gi Kv‡jKUi ‡_‡K T<sub>3</sub> Gi gva¨‡g O/P wmMbvj MÖnb Kiv nq| cykcyj e¨e¯’vi Kvi‡b wecixZ †cvjvwiwU wewkó Kv‡jK±i Kv‡i›U O/P cÖv`vb K‡i| Zvi O/P Gi `ywU mvBW e¨vÛ cvIqv hvq wKš‘ gWy‡jwUs wd«Kz‡qwÍi †Kvb Ask _v‡K bv |

Linear diode Detector Gi mvwK©U WvqvMÖvg mn Kvh©cÖYvjx eY©bv Ki|

DIi t

Composite signal ‡_‡K gyj wmMbvj †K envelope AvKv‡i c„_K Ki‡Z  Linear diode Detector e¨envwiZ nq| Gi O/p , I/P Gi mij ˆiwLK fv‡e cwieZ©b nq e‡j G‡K Linear diode Detector e‡j|

GbwUbv‡Z †h †Kvb Rf signal Induced nq| wKš—y kyay gvG resonant frequency mgvb frequency wewkl& wmMbvj ¸‡jvB LC mvwK©U n‡q Wv‡qvW Gi I/P G hvq Ges Wv‡qvW wU Dc‡iv³ wP‡Gi gZ ïay  c‡RwU cwRkb †K O/P cvVvq | GB cwRwUf envelope Gi nvB wd«Kz‡mwÝ Rf signal C₁ capacitor Øvi evB cvm n‡q hvq |  wKš‘ †jv wd«Kz‡qwÝ ¸‡jv evBcvm  n‡Z cv‡ibv | GB †jv wd«Kz‡qwÝ wmMbvj wU‡Z wWwm wgwkªZ _v‡K hv‡K GKwU R Gi gva¨‡g Wªc K‡i I/P G ïay gvG GKwU original low Frequency information signal cvIqv hvq | hv‡K GKwU K¨vcvwmUi Gi gva¨‡g BbcyU / AvDUcyU G ¸nb Kiv nq|

Foster Sheely Gi mvwK©U WvqvMÖvg mn Kvh©vcÖYvjx eY©bv Ki|

DIi t

Foster Sheely phase detector `yÕwU Balanced Doctor Gi mgš^‡q MwVZ | K¨vcwjs K¨vcvwmUi wW e­wKs Gi Rb¨ L collector current Gi wiUvb© c¨v_ wnmv‡e Ges Wv‡qvW ¸‡jv †iKwUdvqvi wnmv‡e KvR K‡i| Secondary i A cÖvš— hLb + Ve nq ZLb D<sub>1</sub> Forward evqvm cvq| d‡j B‡jKUªb K¨v_W †_‡K A¨v‡bv‡Wi w`‡K hvq Ges L Gi gva¨‡g ‡m›Uvj Uªc G wd‡i Av‡m | Avevi hLY Secondary i B cÖvš— +Ve nq  ZLb D_­2 diqvW© evqvm cvq | d‡j B‡KUªb K¨v_W †_‡K Ab¨v‡bvW Gi w`‡K hvq Geq L Gi gva¨‡g ‡m›Uªvj Uc G wd‡i Av‡m |

Faster sheely Detector Gi cÖvB‡gix Ges †m‡KÛvwi †fv‡ë‡Ri ‰ewkó ¸‡jv wbgœ i“c t

                      i.            f_in = f_e , Primary and secondary 90⁰ out of phase

                    ii.            f_in> f_c , Primary and secondary 90⁰ out of phase

        iii.     f_in>f_c , Primary and secondary 90⁰ out of phase.

Varactor  diode Modulation Gi Kvh©cÖYvjx eY©bv Ki wPG mn |

DIi t

Kvh©cÖYvjx t Varactor  diode Modulation GKwU Frequency Modulator Varactor diode P-N Junction diode hv reverse Boise G †fwi‡qej K¨vcvwmUi Gi b¨vq KvR K‡i | 

GLv‡b ,

V = Applied reverse Voltage

c = Capacitance

mgxKiY wU wPG qvwZ K‡i cvB ,

Varactor  diode †K Lye Kvh©Kvix Kvcwjs K¨vcvwmUi Gi gva¨‡g Awm‡jUi mvwK©U Gi c¨vivjvj G mshy³ Kiv nq| hv‡Z Zv wW Kvcwjs K‡¤úv‡bU Gi Rb¨ Awm‡jUi mvwK©U †_‡K wew”Qbœ _v‡K | gWy‡jwUs wmMbvj †K regulated power supply Gi mv‡_ series G mshy³ Kiv nq| †h †Kvb gyn~‡Z© Varactor  diode Gi Kvh©Kvix evqvm †fv‡ëR gWy‡jwUs wmMbvj m(t) I regulated power supply G i exRMvwbwZ¨K †hvMdj mgvb |

A_©vr , V_vb^(t) = Varactor  diode Gi †h K‡bv gyn~‡Z©i evqvwms †fv‡ëR |

         m (t) = Modulating signal Gi †h K‡bv gyn~‡Z©i evqvwms †fv‡ëR |

          V_dc = Regulated power supply

d‡j gWy‡jwUs wmMbvj Gi gv‡bi cwieZ© n‡j Varactor diode Gi K¨vcvwmwUf gv‡bi cwieZ©b nq| d‡j Awm‡jUi mvwK©U Gi ‡gvU K¨vcvwmUi Gi cwieZ©b nq|

Cordless I Mobile phone Gi g‡a¨ cv_©K¨ †jL|

DIi t

Cordless Phone	Mobile Phone
1. GKwU wbw`ó GjvKv coverage Gi Kv‡R e¨envwiZ nq|	1. GKwU wbw`ó GjvKvi g‡a¨ KvR K‡i|
2. Mobility ‡bB ej‡jB P‡j|	2. gwe‡jwU Gi Rb¨ D‡j­L‡hvM¨
3. mvavbY WvUv ev wfwWI Gi Rb¨ c‡hvR¨ bq|	3. mK‡ji Rb¨ cÖ‡hvR¨
4. Fixed line wnmv‡e we‡ewPZ nq |	4. ‡gvevBj wWfvBm wnmv‡e we‡ewPZ nq|
5. LiP Kg &|	5. LiP †ewk |

AcwUK¨vjm dvBevi wK wK g¨vUwiqv‡ji ˆZwi nq|

DIi t

1.      Silica

2.     Flour zircon ate

3.     Fluoro aluminate

4.     chaloeogenide glesses

5.     Geo₂

6.     B₂o₃

7.     AL₂o₃

AcwUK¨vj dvBevi Gi jvBU †mvm© ¸‡jvi bvg wjL |

DIi  t

1.      LED

2.     Planner LED

3.     Done LED

4.     Superluminiscent LED

5.     Surface Emitter LED

6.     Edge Emitter LED

7.     LASER

‡UwjwcÖ›Uvi wK?

DIi t †UwjwcÖ›Uvi nj GKwU KwgD‡b‡KwUs wWfvBm hv `~ieZx ¯’vb n‡Z †cÖwiZ †Kvb Qwe ,†U¯‹ BZ¨vw` KvM‡Ri Dci Qvcv‡Z e¨envwiZ nq|

Heterodyne Action Kx?

DIi t  Heterodyne Action ej‡Z †Kvb wmMbvj Gi mv‡_ K¨vwiqvi wmMbvj Gi imposing ‡K †evSvq |

AM and FM Gi ga¨Kvi c_©K¨ wjL |

DIi t

Subject:	AM	FM
Band width	Kg	†ewk
Noise	†ewk	Kg
Fidelity	Kg	†ewk
Sensitivity	Kg	†ewk
AM Gi cwieZ©b	nq	nqbv
Frequency	nqbv	nq

Optical fiber Gi ga¨ w`‡q Av‡jvK mÂvjb cÖwµqv eY©bv Ki|

DIi t

AcwUKvj dvBevi Gi †Kvi ,K¬vwWs gyjZ &Av‡jvK mÂvjK Ask MÖnb K‡i|

GLv‡b , μ₁ = Core Gi cÖwZmvs¼

          μ₂ = K¬vwWs Gi cÖwZmvs¼

AcwUKvj dvBevi G Av‡jvK iwkœ GK cÖvš— n‡Z Avi GK cÖv‡š— c~Y© Af¨š—ixb cÖwZdj‡b gva¨‡g †Kvi w`‡q mÂvwiZ nq | Av‡jvK iwkœ msKU †Kvb‡i †P‡q ev eo †Kvb †Kvi G AvcwZZ n‡j Zv c~Y© Avf¨š—ixb cÖwZdj‡bi gva¨‡g GK cÖvš— †_‡K Ab¨ cÖv‡š— Mgb K‡i| `yBwU gva¨‡gi g‡a¨ msKU †Kvb wb‡gœ i m~‡Gi mvn‡h¨ †ei Kiv hq|

Av‡jvK iwk& hw` msKU †Kv‡b  †Kvi G AvcvwZZ nq | Z‡e Zv ‡Kvi G mgvš—iv‡j AcwUKvj dvBevi Gi GK cÖv‡š— †_‡K Ab¨ cÖv‡š— Mgb K‡i| †m dvBevi Gi GKwU gvG Av‡jvK mÂvjb c_ _v‡K Zv‡K wmMbvj †gvW dvBevi e‡j| Avi †h dvBevi Gi GKvwaK Av‡jvK mÂvjb c_ _v‡K Zv‡K gvwë‡gvW dvBevi e‡j | wmMbvj †gvW dvBevi `xN© `~i‡Z¡i †hvMv‡hvM Ges gvwë‡gvW dvBevi Kg `~i‡Z¡i ‡hvMv‡hvMG e¨envwiZ nq wmMbvj †gvW Gi Rb¨ †Kvi AvcZb †Kvb θ_c   †Z nq| GLb AcwUK¨vj dvBevi G AcwUK¨vj wmMbvj θ_c    ev Zvi Pvq‡Z eo †Kv‡b AvcvwZZ n‡j gvwë‡gvW dvBevi Gi Rb¨ Av‡jvK iwkœ ¸‡jv wb‡gœi wP‡Gi gva¨‡g †Kvi Ges K¬vwWs Gi we‡f` Z‡j AvcvwZZ n‡q c~Y© Af¨š—ixY cÖwZdj‡bi d‡j Avevi ‡Kvi I K¬vwWs G cÖwZdwjZ n‡q †Kvi w`‡q Aci cv‡k †Kvi I K¬vwWs | Gfv‡e av°v †L‡Z †L‡Z AcwUKvj dvBevi Gi GK cÖvš— n‡Z Ab¨ cÖv‡š— Av‡jv Mgb K‡i |

 AcwUK¨vj dvBevi Gi MVb cÖYvjx wPG mn eY©bv Ki|

DIi t Optical fiber GK ai‡bi bgbxq KuvP ev c­vw÷‡Ki Zš‘ hv †Kvi (Av‡jvK enb K‡i), Cladding (Av‡jvi cÖwZdjb K‡i) Ges Jacketing (hv AvNvZ ev Av`ªZv †_‡K i¶v K‡i) wb‡q MwVZ GK ai‡bi Av‡jvK evnx bj|

MVb I wPG tÑ cÖavbZ Optical fiber wZbwU Ask h_v    

1.     Core

2.     Coding                                                   

3.     Jacketing                                                                     

                    

eY©bv tÑ

i ) Core : Optical fiber Gi cÖavb Ask nj Gi †Kvi hvi ga¨w`‡q AcwUKvj wmMbvj Mgb K‡i| GUv Lye mi“ I m”Q nq Gi e¨vm mvaviYZ 8μm Gi gZ| GUv KuvP ev c­vw÷‡Ki n‡Z cv‡i †jRvi iwkœ Drcvw`Z AcwUKvj wmMbvj †K A‡bK `~‡i enb K‡i wb‡Z cv‡i|

ii )  Cladding : Optical fiber Gi Ab¨Zg Av‡iKwU cÖavb Ask nj Gi Cladding hv Av‡jvi cÖwZdj‡b ¸i“Z¡c~Y©  f~wgKv iv‡L| ‡Kv‡ii Zzjbvq Cladding  GKwUz Kg m”Q| Gi e¨vm 12 μm Gi gZ nq| Gi cÖwZmi¼ †Kvi Gi †_‡K Kg nq| †Kvi w`‡q cÖevwnZ Av‡jv hLb †Kvi cladding Gi we‡f` Z‡j AvcvwZZ nq ZLb cÖwZd‡bi wbqg Abyhvqx Av‡jvK AcwUK¨vj dvBevi Gi GK cÖvš— †_‡K Ab¨ cÖv‡š— Mgb K‡i| G‡K †Kvi Gi Dci †cPv‡bv nq|

iii ) Jacketing : GUv mvaviYZ K‡qK ¯’i wewkó Am”Q c­vw÷‡Ki hv aZe c`v‡_©i n‡q _v‡K| hv Cladding Gi Dci cPv‡bv nq| †h‡nZz AcwUK¨vj dvBevi †K `xN© `yi‡Z¡i Communication Ki‡j gvwUi wb‡P cy‡Z e¨venvi Kiv nq ZvB cieZ©x‡Z †hb KL‡bv gvwU †Lvovi mgq †Kv`v‡ji ev mvd‡ji ANv‡Z ev gvwUi wb‡Pi Av`ªZv ev mg~‡`ªi †jvbv cvwb‡Z AcwUK¨vj dvBevi Gi †Kvi Cladding ‡K ¶wZMÖš’ Ki‡Z bv cv‡i †mB Rb¨ Jacketing Kiv nq| Gi e¨vm mvaviYZ μm Gi gZ nq|

AcwUK¨vj dvBevi wm‡÷g KwgDwb‡Kkb Gi e­K WvqvMÖvg mn Kvh©vcÖYvjx eY©bv Ki|

DIi t †Kvb Z_¨ GK RvqMv †_‡K Ab¨ GK RvqMvq Av`b cÖ`vb †KB KwgDwb‡Kkb e‡j| Avi GB KwgDwb‡Kk‡b hw` Zvi wnmv‡e AcwUK¨vj dvBevi e¨venvi Kiv nq Z‡e Zv‡K AcwUK¨vj dvBevi KwgDwb‡Kkb wm‡÷g e‡j|

Kvh©cÖYvjx r

Information I/P – Analog information I/P wnmv‡e Voice, text , Music, Video, Data BZ¨vw` e¨venvi nq|

Signal shaping – digital modulation ‡hgb Pem Gi Rb¨ Sampling quantization m¤úY© K‡i| GbvjM gWy‡jk‡bi Rb¨ K¨vwiqvi Introduce K‡i |

Modulation drive – Modulation ckt Gi mvn‡h¨ gWy‡jU wmMbvj Gi SSB,VSB,DSP, Gi †h †Kvb GK GKwU UªvÝwgU G †cÖiY Gi Rb¨ cÖ¯‘Z K‡i | Avi  WªvBf ej‡Z jvBb WªvBf †K eySvq| hv wKbv wmMbvj wU‡K Ggb gv‡b ewaZ© K‡i †`b Zv AcwUK¨vj †mvm© †K WªvBf Ki‡Z cv‡i|

Optical source – I/P electrical signal wU nvB cvIqvi LED Gi gva¨‡g AcwUK¨vj wmMbv‡j i“cvš—i nq|

Transmit media fiber – Optical signal wmMbvj †K T_x ‡_‡K R_x enb K‡i|

Optical decoder – AcwUK¨vj wmMbvj †K d‡Uv Wv‡qvW Gi gva¨†g B‡jKwUªK¨vj wmMbv‡j i“cvš—i K‡i|

Amplifier - ‡h‡nZz d‡Uv Wv‡qvW Gi BbcyU LyeB `ye©j ZvB G‡K Amplifier w`‡q Gg gv‡b ewa©Z Kiv nq hv‡Z GwU ciewZ© wmMbvj †K WªvBf K‡i |

Decoder – gWy‡j‡UW I‡qf †_‡K K¨vwiqvi †K wg¯‹vi Øviv †jvKvj Awm‡jUi Gi mvn‡h¨ `~i K‡i|

Information I/P – GKwU †jv cvm wdëvi e¨venvi K‡i Bbdi‡gkb AvDcyU G †bIqv nq|

122. wPG mn g‡Wg Gi KvR e¨vL¨v Ki|

DIi t

g‡Wg mvaviYZ GbvjM Ges wWwRUvj ‡bUIqv‡K©i gva¨‡g m¤úK© ¯’vc‡b e¨venvi nq| wb‡P GKwU g‡Wg Gi Kv‡bKkb †`Lv‡b nj t

A_©vr g‡Wg gWy‡jkb I wW-gWy‡jkb DfqB K‡i | g‡Wg GbvjM wmMbvj ‡K wWwRUvj wmMbvj  Ges wWwRUvj wmMbvj †K GbvjM G i“cvš—i K‡i| G Rb¨ Kw¤úDUvi †K PSTN  †bUIqvK© Gi mv‡Z hy³ Ki‡Z g‡Wg e¨envwiZ  nq| GLv‡b , Kw¤úDUvi Gi wWwRUvj WvUv †K g‡Wg PSTN †bUIhvK© Gi UªvÝwgU Kivi c~‡e© Zv‡K GbvjM wmMbvj G i“cvš—i K‡i| Avei PSTN †bUIqvK© †_‡K wmMbvj †K KwgDwb‡Kkb G cvVv‡Z wWwRUvj WvUv †Z i“cvš—i K‡i|

†gvevBj KwgDwb‡Kk‡b e¨venwiZ wWfvB mg~‡ni bvg wjL।

DIi t

        i.            Sencor

      ii.            Pager

    iii.            Personal digital Antenna

   iv.            Note Book Laotop

     v.            Embeded Controller

   vi.            Mobile Phone

†mUvjvBU Gi Avc wjsK Ges WvBb wjKs wd«Kz‡qwÝ KZ?

DIit

AvcwjKs wd«Kz‡qwÝ mvaviYZ 5.75 †MMv  nvR©

WBb wjsK wd«Kz‡qwÝ mvaviYZ 3.45 †MMv nvR©

Telephone exchange G e¨evnwiZ cÖ‡UvKj wWfvBm mg~‡ni bvg wjL |.

DIi t

1.      Fuse

2.     Heating Coil

3.     Carbon Block

4.     Light Protecting Device

Side tone Kx? Side tone wK m¤úY© AbvKvw•LZ?

DIi t e³vi Microphone Gi K_vB real time G Zvi wb‡Ri w¯úKv‡i  †kvbv hvq | Ges G‡¶‡G e³viv  Lye †Rv‡o K_v ej‡j †m Zvi wb‡Ri kãwU Zxeª wi‡qj UvBg cÖwZaŸwb ky‡b hv Lye weiw³ Ki| G mgm¨ `~i Kivi Rb¨ †Uwj‡dvb wm‡÷‡g G exchange ‡_‡K GK ai‡bi G¨vKwUf DRvi wdWe¨vK wmMbvj me©`v †cÖiY Kiv nq hvi †_‡K eySv hvq †h wj‡mbvi e³vi K_v ïb‡Q GB †cÖiY tone †K Side tone e‡j|

UªvÝwgkb wgwWqv ej‡Z wK eySvq?

DIi t hv wKQzi ga¨ w`‡q wmMbvj GK ¯’vb †_‡K Ab¨ ¯’v‡b Mgb K‡i Zv‡K UªvÝwgkb wgwWqv e‡j|

                                                                                                                 

 AcwUK¨vj dvBevi ˆewkó mg~n wjL |.

DIi t

1.      Lye Kg WvUv jm nq |

2.     Wider band width

3.     AvK‡i †QvU

4.     IR‡b nvjKv

5.     AwaK wbivc`

Frequency Allocation ej‡Z wK eySvq?

DIi t wd«Ky‡qwÝ Gi gvb †K wewfbœ †iÄ G fvM K‡i ‡h MÖ“wcs Kiv nq Zv‡K Frequency Allocation e‡j|

AcwUK¨vj wmMbvj Gi gvwë‡c¯‹ Ges wW-gvwë‡c¯‹ eY©bv Ki|

DIi t

AcwUK¨vj dvBevi KwgDwb‡Kkb G MwZ e„w× Kivi Rb¨ I/P Section G GKvwaK AcwUK¨vj wmMbvj †K GKwU gvwë‡c­¯‹ Gi mvnv‡h¨ GKwU wmMbvj G i“cvš—i Kiv‡K gvwë‡c­¯‹ e‡j|

Avevi O/P section G GKwU wmMbvj †K GKwU wW-gvwë‡c­¯‹ w`‡q GKvwaK wmMbvj G i“cvš—i Kiv‡K wW-gvwë‡c­¯‹ e‡j|

†iwWI wmMbv‡j If frequency Gi gvb KZ?

DIi t 455wK‡jvnvR© †_‡K 665 wK‡jvnvR© ch©š—

LAN Gi ‰ewkó mg~n wjL।

DIi t

1.      Wider Band width

2.     Data transmit speed ‡ewk |

3.     ‡QvU GjvKv wb‡q MwVZ |

4.     G‡Z wiwcUvi e¨envwiZ nq|

WAN Gi ˆewkó mg~n wjL।

DIi t

1.      Band width mxwgZ

2.     Data transmit speed Kg |

3.     A‡bK we¯‘„Z GjvKv wb‡q MwVZ

4.     G‡Z wiwcUvi e¨envi nq bv |

Hub Kv‡K e‡j?

DIi t †h †m›Uvivj Kv‡bKwUs wWfvB‡mi gva¨‡g GKvwaK mvf©vi †K Star topology †Z  ms‡hvM Kiv nq Zv‡K Hub e‡j|

AcwUK¨vj dvBev‡i e¨envwiZ †mbmi ¸‡jv wK wK?

DIi t

1.      Intercity Modulation Sensor

2.     Phase Sensor

3.     Detraction Sensor

4.     Chemical Sensor

5.     signal mode fiber

6.     Medical sensor

LAN and MAN Kx?

DIi t

LAN –  mvaviYZ GKwU †QvU Storage Building Gi wKQz PC †K  ci¯ú‡ii  g‡a¨ WvUv exchange Kiv nq|

MAN – mvaviYZ MAL,LAN Gi Pvq‡Z A‡bK †ewk PC ci¯ú‡ii mv‡_ ms‡hvM Kivi Rb¨ GUv e¨venvi Kiv nq|

†cÖvUKj Gi Dcv`vb mg~n wjL?

DIi t

1.      Syntax

2.     Semantics

3.     Timing 

AcwUK¨vj dvBevi Gi Sensor Gi KvR wK?

DIi t

1.      GKwU `ye©j wmMbvj †K ewa©Z Kiv |

2.     GKwU cÖ‡mm‡K cwigvc K‡i|

3.     ‡cÖvqRbxq WvUv A‡Uv‡gwUK¨vjx †iKW© K‡i mgq gZ e¨venvi K‡i|

FDM Gi cÖwµqv eY©bv Ki|

DIi t

FDM – Frequency division Multiplex . FDM G GKvwaK †em e¨vÛ wmMbvj ‡K wewfbœ wd«Ky‡qwÝ wewkó K¨vwiqvi I‡qf Gi mv‡_ gWy‡j‡UW Kiv nq| Ges  G‡`i †K hy³ K‡i GKwU K¤úwmU wmMbvj ˆZix Kiv nq | GB wmMbvj wU‡K AcwUK¨vj P¨v‡bj G †cÖiY Kiv nq| Z‡e K‡¤úvwms wmMbvj †_‡K P¨v‡bj Gi e¨vÛ IqvBW Aek¨B †ewk n‡Z n‡e| GKB dvBevi G GKvwaK P¨v‡bj e¨vevn‡ii Rb¨ cÖwZwUi P¨v‡bj Gi SeparationGi Rb¨ GKwU guard band e¨envwiZ Kiv nq| wWgvwë‡c­¯‹ Gi wdëvi e¨envi Kiv nq| GK GKwU wdëvi GK GKwU gWy‡j‡UW wmMbvj †K cvm K‡i | GB gWy‡j‡UW wmMbvj ¸‡jv‡K GKwU wg¯‹vi Øviv K¨vwiqvi wmMbv‡ji mvnv‡h¨ g~j wmMbvj †K cybi“×i Kiv nq|

PCM Gi †KvwWs Ges quantizing Gi mwPG eY©bv `vI।

DIi t

PCM – Pulse code Modulation G GbvjM wmMbvj †K wWwRUvj G i“cvš—i Ki‡Z GbvjM wmMbvj Gi Ggwc­Pz‡qW Gi †iÄ †K KZ¸‡jv ÷ªvÛ ev Av`©k ‡j‡fj G fvM Kiv nq| Ges †j‡fj Gi msL¨v 2 Gi cvIqvi nq| e¨envwiK †¶G †j‡fj msL¨v 128 ch©š— ev Zvi Pvq‡Z †ewk nq| AsK‡bi myweav‡_© GLv‡b 8wU †j‡fj †`Lv‡bv nj

Sampling pulse Gi Ggwc­Pz‡qU †K wbKUeZ©x Av`k© †j‡f‡j i“cvš—i Kiv‡K quantizing e‡j| quantizing Gi mgq †j‡fj ¸‡jv‡K Zv‡`i Avmbœ gv‡b DbœZ Kivi mgq wKQz B‡ivi aiv nq| GB B‡ivi ¸‡jv‡K quantizing B‡ivi ejv nq|

PCM Gi e­K WvqvMÖvg mn Kvh©cÖYvjx  eY©bv Ki|

DIi t

Band pass filter – wbw`ó e¨vÛ Gi wmMbvj †K wdëvi K‡i|

Sampling & hold ckt – Analog continuous Value signal Gi Amplitude ‡K w¯’i iv‡L|

A/D converter – G¨vbvjM wmMbvj †K wWwRUvj wmMbv‡j i“cvš—i K‡i|

Parallel to serial converter – Parallel input data ‡K wmwiqvj BbcyU WvUv ‡Z i“cvš—i K‡i|

Repeater – wWwRUvj wmMbvj †K nq GKwU wbw`wó gv‡b ewa©Z K‡i bv nq wbw`ó gv‡b n«vm K‡i|

Serial to parallel Converter – wmwiqvj BbcyU WvUv †K c¨vivjvj BbcyU WvUv‡Z i“cvš—i K‡i |

D/A converter – wWWRUvj WvUv‡K GbvjK WvUv‡Z i“cvš—i K‡i|

143. FDDI Gi mwPG eY©bv `vI?

DIi  t IEEE 802 base LAN Gi weKí n‡jv hv D”P MwZi WvUv UªvÝwgkY Gi Rb¨ D‡j­L †hvM¨ LAN c×wZ |

Sampling TheoremwjL।

DIi t Sampling Frequency Gi gvb gWy‡jwUs wmMbvj Gi m‡e©v”P gvb Gi Kgc‡¶ wظb  n‡j ‡m¤úwjs wmMbvj †K cybi“×vi Kiv hvq|

 Facsimile Gi gyjbxwZ wjL।

DIi t Transmitting end information †K GKwU Scanner Øviv Scan K‡i G‡K Dchy³ †KvW wmMbvj G i“cvbZi K‡i Gi mv‡_ Conscription I address Ry‡o w`‡q UªvÝwgU K‡i| wiwmfvi GB wmMbvj wU wiwmf K‡i decryption I Decoding K‡i Receiver Fax machine Gi †ccvi G wcÖ›U K‡i |

Crystat filter Gi KvR wK?

DIi t w¯’i wd«Ky‡qwÝ Drcbœ Kiv |

Insertion Loss wK ?

DIi t †Kvb UªvÝwgkb jvBb Gi ga¨ w`‡q wmMbvj †cÖvcv‡Mkb Gi mgq Gi gv‡bi †h n«vm nq Zv‡K Insertion Loss e‡j|

Exchange Kx? Gi †kªYxwefvM †`LvI?

DIi t Exchange – Telephone servic Gi †¶‡G †h c‡q›U G e¨venviKvwi Mb ¯—vqx ev A¯—vqx fv‡e mshy³ _v‡K Zv‡Z Exchange e‡j|

Local battery and contral Battery Exchange wK?

DIi t

Local battery Exchange – †h Exchange system G e¨venviKvix †mU G e¨vUvix e¨venvi Kiv nq Ges e¨vUvix †kl n‡j cybivq e¨vUvwi wi‡c­m Kiv nq Zv‡K †jvKj e¨vUvix GK‡Pb&R e‡j|

Control battery exchange - ‡h Exchange system G e¨enviKvix †mU e¨vUvix e¨envi bv K‡i ExchangeG e¨vUvix e¨evnvi Kiv nq Zv‡K contral Battery Exchange e‡j|

SSB Kx?

DIi t gWy‡jkb wmMbvj Gi †h †Kvb GKwU e¨vÛ †K wmMbvj mvBW e¨vÛ ev SSB e‡j|


 Satellite communication Gi gyjbxwZ †jL |

DIi t Satellite communication Gi †h ‡Kvb Av_© †÷k‡b wU I‡qf wjsK Gi gva¨‡g AvcwjsK wd«Ky‡qwÝ †Z Bbdi‡gkb ‡K †mUvjvBU Gi D‡Ï‡k¨ †cÖib K‡i hv ‡mUvjvU MÖnb K‡i cÖ‡qvRbxq cÖ‡mwms †k‡l Avevi Aci †Kvb wWmwU‡bk‡b ‡cÖiY K‡i|

LASER Gi c~Y ©A_© wjL।

DIi t LASER – Light Amplifier  by stimulated Emission of Radiation

PAM I PWM Gi e¨envi wjL।

DIi t

PAM – UªvÝwgUvi Gi BbcyU †K w¯’ i ivL‡Z

PWM- UªvÝwgUvi I wiwmfv‡ii g‡a¨ synchronizing Ki‡Z |

VSB ej‡Z wK eySvq?
DIi t Transmitting section G †h †Kvb GKwU mvBW †K m¤úY© i“‡c I Aci mvBW †K AvswkK i“‡c UªÝwgU Kivi Rb¨ †h gWy‡jkb e¨venvi Kiv nq ZvB VSB |

GPS Gi mwPG eY©bv `vI।

DIi t GPS – Global Positioning system

Bnv GKwU ‡iwWI †emW †b‡Mkb wm‡÷g hv mvaviYZ Military Communication Gi Rb¨ I KwgDwb‡Kkb Kv‡R e¨envi G Rb¨ wWRvBb Kiv nq| GPS gvwUi Dci †h †Kvb RvqMv‡K AwZ mn‡R wPý Z Ki‡Z cv‡i| G Rb¨ GPS wegv‡b , Mvwo‡Z GgbwK Rvnv‡RI e¨envi Kiv nq|

eY©bv t GPS Gi cÖavbZ 3 wU Ask

1.      Space segment

2.     Control segment

3.     User segment

Space segment – Space segment 24 wU m¨vUvjvBU wb‡q MwVZ | GPS Satellite mg~n gvwU †_‡K 20,200 wKtwg Dc‡i e„IKvi K¶c‡_ Aew¯’Z| G`i AiweUvj wcwiIW 11  N›Uv 58 wgwbU Ges ci¯úi 55⁰  †Kvb Aew¯’Z| 24 wU †mUvjvBU Gi 21wU KwgDwb‡Kkb wm‡÷‡g Ges 3 wU K‡›Uªvj wm†÷‡g e¨venvi nq|

Control segment – GB Ask we‡k^ wewfb As‡k AvcvwZZ †mUvjvBj m‡gy‡ni wbqš¿‡b I mKj †mUvjvBU mg~‡n wbqš¿‡b e¨envwiZ nq| GB As‡ki Rb¨ GKwU gv÷vi K‡›Uªvj ‡÷‡Ukb e¨envwiZ nq|

User segment – GPS receiver mg~‡ni mvgwqK I †emvgwqK Kv‡R e¨envwiZ nq| GPS receiver ‡÷kb KZ…K †cÖwiZ wmMbvj †K wW‡KvwWs K‡i Zv‡`i ci¯ú‡ii `~i‡Z¡i wb‡R‡`i DPPZv I mgq wbY©q Ki‡Z cv‡i|

SSB(signal side Band )Transmission Gi e­K WvqvMÖvg mn Kvh©cÖbvjx eY©bv Ki|

DIi t wb‡gœ GKwU wP‡G signal side band Transmission Gi e­K WvqvMªvg mn Kvh©cÖYvjx eY©bv Kiv nj t

Crystal Oscillator – Gi mvn‡h¨ GKwU wbw`ó g‡bi K¨vwiqvi wd«Ky‡qwÝ Drcbœ Kiv nq| D³ wd«Ky‡qwÝ †K GKwU e¨v‡jÝ gWy‡jkb G cÖ‡qvM Kiv nq|

Audio Amp – AwWI Aw¤údvqvi Øvi 0.1 wK‡jvnvR© - 3 wK‡jvnvR© Gi AwWI gWy‡jkb wmMbvj †K ewa©Z K‡i e¨v‡jÝ gWy‡jU‡i †`Iqv nq|

Balance Modulator – Crystal  oscillator  ‡_‡K AvMZ K¨vwiqvi wmMbvj Ges AwWI A¨vgwc­dvi †_‡K AvMZ gWy‡jwUs wmMbvj †K e¨v‡jÝ gWy‡jUi Gi mvn‡h¨ A¨vgwc­Pz‡hW gWy‡jkb K‡i K¨vwiqvi mv‡cÖmW Kiv nq|

Band pass Filter – Band pass Filter carrier mv‡cÖmW gWy‡j‡UW wmMbvj Gi GKwU mvBW e¨vÛ †K ev` w`‡q Avcvi mvBW e¨vÛ MÖnb Kiv nq|

Power Amp – Band Pass Filter ‡_‡K AvMZ 100.1 - 103 wK‡jvnvh© Gi Avcvi mvBW e¨vÛ †K cvIqvi A¨vw¤údvqi Øvi ewa©Z K‡i cÖ_g wg¯‹vi Gi mv‡_ †cÖvqM Kiv nq|

1^st Oscillator – Gi mvn‡h¨ 3 MHzGi GKwU wmMbvj Drcbœ Kiv nq| Drcbœ wmMbvj †K 1^st Mixer G cÖ‡qvM Kiv nq|

1^st Mixer – Power Amp ‡_‡K AvMZ Ges 1^st oscillator †_‡K AvMZ GKwU wmMbvj †K 1^st Mixer G Heterodyne action NUv‡bv nq| d‡j †hvM dj AvKv‡i GKwU I we‡qvM dj AvKv‡i GKwU wmMbvj Drcbœ nq hv‡`i wd«Ky‡qwÝ h_vµ‡g 3.1001 -3.103 †gMvnvR© Ges 2.897 - 2.99 †gMvnvh© Gi wmMbvj †K e¨vÛ cvm wdëvi G gva¨ w`‡q 2^nd Mixer G cÖ‡qvM Kiv nq|

Second oscillator – Gi mvn‡h¨ 12 †gMvnvR© Gi GKwU wmMbvj Drcbœ Kiv nq| Drcbœ wmMbvj †K 2^nd Mixer G cÖ‡qvM Kiv nq|

2^nd Mixer – 1^st Mixer n‡Z AvMZ Ges 2^nd oscillator  †_‡K AvMZ hvi GKwU wmMbvj †K GLv‡b Heterodyne action NwU‡q †hvMdj AvKv‡i I we‡qvMdj AvK‡i GKwU wmMbvj Drcbœ K‡i hv‡`i wd«Ky‡qwÝ h_vµ‡g 15.1001 - 15.103 †gMvnvR© Ges 8.837- 8.8999 †gMvnvh© nq|

Final Power Amplifier – 2^nd Mixer n‡Z AvMZ 15.1001 - 15.103 †gMvnvR©  nq Gi wmMbvj †K dvBbvj cvIqvj A¨vwc­dvB Øvi ewa©Z K‡i UªvÝwgkb GbwUbv Gi gva¨‡g UªvÝwgU Kiv nq|