Philips TW0200 manuale d’uso

Chapter 7[...]

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7-1.5 Meters for M/W System 1. Power Meter Anritsu - ML 4803 A 2. Power Meter HP - 437 B, 4368, Philips 3350 3. Spectrum Analyzer- Anritsu MS 7101 B,10 KHz- 23 GHz, 22 GHz- 140 GHz. 4. M/W System Analyzer (MSA ) Transm itter & Receiver ME 538 M Anritsu 4510 B Transmitter and Receiver. 5. M/W frequenc y counter Anritsu MF 76 A 6. Sweep Generator[...]

7-1.6 Before proceeding any M/W system A/T --------- 1] Get TT-O, TT-1 duly filled in all respect, 2] Collect Survey report which includes, - Check list - Route details - Site survey report - Particulars at a glance - Clearance calculation - Path data calculation - Rain attenuation calculation - Availability calculation - Interference calculation -[...]

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7-2 MICROWAVE SYSTEM A/T Microwave A/T comprises of - Local A/ T of all stations, and Repeaters. - Hop Test. - Through Test. 7-2.1 Local A/T:- There are several makes of Narrow / Wide band m icrowave systems, near about all test are same except power suppl y points, access points. Here for ex ample Satara M/W station to T.E. end link of 11 GHz (1+ [...]

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3. Test on receiver :- - Check of RLO frequency :- Check of RLO frequency with unritsu or HP frequency counter, measure frequency and offset - Write assigned measured and deviation in PPM lim it ±20 PPM - Measure RLO output level at RLO mon limit ≥ -12 dBm - Feed Receive RF frequency at a level of -30 dBm at RX, RF and record - 1.RF frequency li[...]

7-2.2 VSWR: - Voltage standing wave ratio Standing wave :- If the impedance of the load (Ant enna) and source ( Generator ) is not equal, that is not matching then part of the energy is reflected back towards the source., some power is absorbed and rest is reflected .this interference form one set of waves V & I traveling towards the load and r[...]

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MSA Transmitter Fig. 7-10 Conversion chart of VSWR, Return Loss and SW R. VSWR Return loss In dB Reflection Coefficient SWR In dB 1.01 46.1 0.5 0.086 1.02 40.1 1.0 0.172 1.03 36.6 1.5 0.257 1.04 34.2 2.0 0.341 1.05 32.3 2.4 0.424 1.06 30.7 2.9 0.506 1.07 29.4 3.4 0.588 1.08 28.3 3.8 0.668 1.09 27.3 4.3 0.749 1.10 26.4 4.8 0.828 1.11 25.7 5.2 0.906 [...]

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Please see the W iltron diagram, Anritsu detector converts power into voltages. - Connect Open , select - Connect Short , select - Connect device , - Start select, - Function, - Max /select -20 dBm, - Min / select -34 dBm, - Cursor also move for max to minimum. Wiltron Generator: - See Fig. 7-1 2, 7-13. - Take 10.7 to 11.7 GHz - Level +10 dBm ( + 7[...]

182 . Check of BER with IF Loop: - oop IF Trans to If Receive and test 140 Mb/ STM-1 on DTA set for 0 PPM and ± 15 PPM. The result should be 0.00 E -11 5. a) Trans Branching Filter loss: - The difference between Trans Power at PA out and antenna port will be a Trans Branching Filter loss. b) Receive Filter loss: - Feed RF Frequency at a nominal le[...]

7-2.4 HOP A/T OF 11 GHz 140 Mbps or STM-1 1] Receive level : - Note down Surveyed level, Nom inal level and measure Rx RF level at Rx IN by power meter with suitable sens or and pad by removing the W/G from RF IN. m - The same Rx RF l evel can be eas ured with calibrated spectrum analyzer and by ed een survey ed and nominal level should be within ?[...]

4] BER measurement:- - Ask distant station loop on 140 Mb or STM-1 which is installed. - Carry out BER Test as usual for 0 and ± 15/20 PPM. - Take out printout for each channel/PPM , - Limit: - 1x 10 E -11 5] i Carr on channels for the following freq Filters as HP-1+LP & HP-2 +LP. o ± 15 or 20 PPM t 0 PPM, note down the ber 8] Check of ORDER [...]

which transmits and receives Radio sig nals agnetic waves. Antenna used for the transmission of Radio, TV, , GSM and CDMA network. y in all direction) nal antenna of array of dipoles. - Parabolic: - It is made up of 2 to 4 meter diameter nd its components are Reflector, Feed, Support (Tie beam) ----------------- ------------- Or ------------ Λ (Wa[...]

7-3.2 3. Link Budget:- Link budget is to calcula Receive level taking into consideration all gains and losses in the ne rk. It accounts atte nuation of transm itted FL – Br Where ns. not for at antenna port. e.g. Free space loss = 20 log FD + 92.4 = 144.60 dB Meter.) 91.20 dB 30.0 dBm Calculated Receive le vel = - 36.52 dBm ith thick blanket in d[...]

7-3.3 5. Fresnel zone: - No. of concentric ellipsoid revolutions whic h defines volumes in radiation pattern of ircular aperture and it is due to diffraction by circular aperture ar in cross s ection and concentric near th e path of radio beam. TR – Direct path and TAR – ary transmission path eflection of M/W energy from A. in radio system fadi[...]

-3.4 8. Rain attenuation: - As the water droplets scatters and absorb s radiation the effect of es on increasing with the increase of fr equencies i.e. it is more in 13 GHz system GHz stance likely size of rain cell i.e. by space diversity. in 1+1 traffic, called es, cost of the version of the same signal are transm itted at different time instance[...]

Antenna diversity: - In this diversity sc hem microwave signals are transmitted along st instantaneously on failure of 11 Thi for ove 1. B 2. Frame Synch loss when BER >10 3. CMI O/P to Mux is lost Here Priority is 3>2>1 Process:- - Fault in reg annel detected at receiving end. - Faulty cha l switching control is tr ansmitte received end t[...]

13. Wayside dropping: - If any small station in any hop requires 2 MB stream, an additional card is provided in system so as to handle th e traffic of small station along with main M/W system. fferential Absolute Delay Equalizer. It is to adjust the phase difference between signals received through 15. ATPC: - Automatic Trans Power Control. ATPC fa[...]

7-4 2 GHz / 8 MB D/ UHF System A/T Make: - ARM-2208-M3 Specification: - 7-4.1 - Frequency band 2.0 to 2.3 GHz. range 45 dBm for threshold. - Ref Rec. I/P level -42 dBm ± 1 dBm. - Overload of LNA -35 dBm or better. Bm at Rx In. - O/W response ± 2 dBm. 7 nal level, the deviation should not be more than ± 3 dBm. - Mostly towers are existing but whe[...]

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- Disconnect RF cable from Rx In. - Make a test set up as above for AGC calibration. - Select RF frequency and level say -40 dB m and calibrate it for the correct O/P level. - Put ON RF O/P and monitor AGC voltage. - Note down AGC voltage up to -75 dBm in steps of -10 dBm and there after in 5 dBm steps when E -3 LED lights. - Reading will be -86 to[...]

7-4.4 HOP/ through A/T 1. Receive level: - - Measure RF Rx level at Rx IN a nd compare it with surveyed level. Deviat - ion between surv eyed and measured le vel should be within ±1 dBm. 5 minutes each. n: - m distant station. - r channel. as been switched to Same observe by making receiver off. - d ask other end to observe protection switching. -[...]

- Tele command status TC1, TC2 OFF. - supervisory card out. - ous alarm on Transm itter . - / front pane l synthesizer go es 0/0 lock. ecovered. arranging loop from other station. % DM 0.045 7-4.5 C ial Feeder. /8 coaxial Cu 50 Ω . 9.1 mm. 28.9 mm er. 6. BITE Alarms: - - Eqpt fail: - Any Eqpt failure. - System fail: - Any System failure. Micropro[...]