Sercel LRU User Manual LRU user

Sercel Inc LRU user

User Manual

March 2002LRU User Manual
In no event shall SERCEL be liable for incidental or consequential damages or related expensesresulting from the use of this product, or arising out of or related to this manual or the informa-tion contained in it, even if SERCEL has been advised, or knew or should have known of thepossibility of such damages.The information included in this documentation is believed to be accurate and reliable.However, SERCEL reserves the right to make changes to its products or specifications at anytime, without notice, in order to improve design or performance and to supply the best possibleproduct. This documentation does not form in any way a contractual agreement of salespromise on the part of SERCEL.Software mentioned in this documentation is sold under a precise licence agreement and assuch the documentation may cover technical areas for which the user may not have a finallicence.No part of this documentation, or any of the information included herein may be modified orcopied in any form or by any means without the prior written consent of SERCEL.Acknowledgments: All brand or product names are trademarks or registered trademarks oftheir respective companies or organizations.To contact SERCELNantes, FranceCommercial; Customer Support;Manufacturing & Repair.B.P. 439, 16 rue de Bel Air44474 Carquefou CedexTel: +33 2 40 30 11 81, Fax: +33 2 40 30 19 48Hot-Line: Land: +33 2 40 30 58 88Marine: +33 2 40 30 59 59E-mail: sales@sercel.frcustomer.support@sercel.frwww.sercel.comSt Gaudens, FranceVibrator Customer Support;Vibrator Manufacturing & Repair;Streamer Manufacturing & Repair.Tel: +33 5 61 89 90 00, Fax: +33 5 61 89 90 45Hot Line: +33 5 61 89 90 91Alfreton, U. K.Streamer Manufacturing & Repair;Customer Support.Tel: +44 1 773 605 078, Fax: +44 1 773 541 778Houston, USACommercial; Customer Support;Manufacturing & Repair;Streamer Manufacturing & Repair.Tel: +1 281 492 66 88, Fax: +1 281 492 69 10Hot-Line: +1 281 492 66 88E-mail: sales.hou@sercelus.comtraining.hou@sercelus.comcustomer.support@sercelus.comPonca City, USAVibrator Customer Support;Vibrator Manufacturing & Repair.Tel: +1 580 763 00 00, Fax: +1 580 763 00 22Moscow, RussiaCommercial; Customer Support.Tel: +7 095 254 06 59, Fax: +7 095 254 66 80Beijing, P. R. of China Commercial; Customer Support.Tel: +86 106 43 76 661, Fax: +86 106 43 76 307Tanggu, P. R. of ChinaManufacturing & Repair.Tel:+86 222 58 23 224 , Fax:+86 222 58 23 242Xian, P. R. of ChinaManufacturing & Repair.Tel: +86 297 85 25 05, Fax: +86 297 85 55 04SingaporeStreamer Manufacturing & Repair;Customer Support.Tel:+65 545 0411, Fax:+65 545 1418Dehradun, IndiaCustomer Support.Tel: +91 135 773 387, Fax: +91 135 773 132E-mail: sercel@nde.vsnl.net.in
LRU User Manual 1-1GeneralThe LRU (Line Remote Unit) relay is a long range point-to-point radiorelay cell that can be inserted anywhere in a spread as an element of the408UL network to relay the data transmission on a Line or a Transverse.It connects to any type of 408UL field electronics (LAUX, LAUL, FDULink, etc.). Built in the LRU is a full performance LAUX.In the LRU transmission protocol (Half-duplex), time is shared betweentransmission of Master-to-Slave messages and transmission of Slave-to-Master messages.Master-to-Slave messages are called Network Control Sequences(NCS), used for synchronization, zero-time transmission and control.Slave-to-Master messages are called Data Transfer Sequences (DTS),used for data retrieval, seismonitor and collecting test results.
Typical setups1-2 March 2002Typical setupsCAUTIONIf you wish to test a radio relay cell through a wireline link between the coaxial connectors of two LRUs, use a 60 dB (minimum), 20 W attenuator. 20 W60 dB min.12 V 12 VAttenuator(test setup)LRU12 VLRU12 VNOLRU12 VLRU12 VYESFor optimal performance of the radio link, do not place any electric device (including LRU, FDPA408, etc.) on the same side as the radiating elements!Do not raise any antenna near electric power distribution lines!The antenna should be at the top the mast.8 mUse the whole cable lengthto keep clear from the antenna.
LRU User Manual Typical setups 1-3CAUTIONAntenna height is limited to 6.1 metre near airports.Below are typical examples of setups along with the associatedspecifications in terms of covered range and transmission capacity.Basic radio relay cell. Typical performance (Ground-Wave propagation above flatterrain):- Range: 24 km, 60 Ch @ 2 ms, Real time.- Range: 10 km, 240 Ch @ 2 ms, Real time.See CAUTION on page 1-2.For the Left/Right and Low/High ports of the LRU, connect as usual(Left to Right; Low to High).LRU12 VLAUX and UnitTransverseto Centralradio functionsLine or LRU12 VCoax downlead1Seebelow7-elementYagi antennaBattery1
Typical setups1-4 March 2002Radio relay in series connectionTo extend the relay range, you can use two relay cells in seriesconnection as shown below. You can choose between two types ofseries setups, one with fewer antenna masts to raise, the otheroptimizing the data rate.• Two-mast series setup (high data rate) Typical performance of each relay cell (Ground-Wave propagationabove flat terrain):- Range: 24 km, 60 Ch @ 2 ms, Real time.- Range: 10 km, 240 Ch @ 2 ms, Real time.Setups with more than two relay cells in series connection have not beentested yet.See CAUTION on page 1-2.LRU12 VUnitTransverseto CentralLine orLRU12 V1SeebelowBattery LRU12 VLRU12 V1SeebelowRequirements:- At least 300 m between antennas,- At least 13 MHz frequency separation.Transverse portsLine orFor optimalperformance,use vertical polar-ization in one celland horizontal inthe other.1
LRU User Manual Typical setups 1-5• Single-mast series setup Typical performance of each relay cell (in Ground-Wavepropagation conditions above flat terrain):- Range: 24 km, 30 Ch @ 2 ms, Real time.- Range: 10 km, 120 Ch @ 2 ms, Real time.For the single-mast series setup, a special software configuration needsto be programmed in the LRUs, using an FDPA408 pocket terminal orthe 408UL HCI workstation: in each intermediate pair, not to have oneof the LRUs transmitting while the other is receiving, you must havethem working on two distinct “Subframes”. That’s why the date rate isdivided by two in the above example.See LRU Operational Description.LRU12 VUnitTransverseto CentralLine orLRU12 V1SeebelowBattery LRU12 VLRU12 V1Seebelow(Line orTransversecable)1
Typical setups1-6 March 2002Where more than two relay cells are used in “single-mast seriesconnection”, you can avoid reducing the data rate any further if you stillwork with only two Subframes, provided adjacent relay locations do notuse the same Subframe.In the example below, relay cell (A) can use the same Subframe as relaycell (C) if they are distant enough and if they use two separate frequencychannels.Relay Cell LRU No. Transmit on Subframe 1 Transmit on Subframe 2(A) 1✔2✔(B) 3✔4✔(C) 5✔6✔LRU 1LRU 2LRU 3LRU 4LRU 5LRU 6(A)(B)(C)
LRU User Manual Typical setups 1-7Radio relay with REM Typical performance of each relay cell (in Ground-Wave above flatterrain):- Range: 24 km, 60 Ch @ 2 ms, Real time.- Range: 10 km, 240 Ch @ 2 ms, Real time.The antenna of the REM and the antenna of the LRU attached to thatREM can be mounted on the same mast, but in that case a minimumvertical separation of 30 metres (100 feet) should be provided. The ruleis to have at least 80 dB attenuation between the two antennas to alloweach system to work at its full sensitivity. The cavity filters for theREMs are still required.A REM upgrade may be required.See CAUTION on page 1-2.LRU12 VUnitTransverseto CentralLine orREM12 V1SeebelowBattery LRU12 V(Transverse cable)Insert acavity filter forRequirements:- At least 300 m between antennas,- At least 13 MHz frequencyseparation.bandpasseach REM(case of multi-REMsetup) and onemore if Audio isused with SU6-RSU6R SU6R SU6R1
Typical setups1-8 March 2002LRU12 VREM12 VLRU12 VRequirements:- At least 300 m between antennas,- At least 13 MHz frequencyseparation.REMSU6RSU6RSU6RSU6R12 Vup to 24 km
LRU User Manual Antennas 1-9AntennasThe LRU is used as a point-to-point radio relay. For a stationary relay,directional antennas are used, allowing maximum performance andprotection from interference. Where one of the two LRUs involved in aradio relay is subject to roving (Marine, Shalow-water operation, etc.)omni-directional antennas are more suitable.Directional antennaBelow are the specifications of a wide-band, 7-element Yagi antennaavailable from SERCEL.This directional antenna can be used either horizontally or vertically.A 50-ohm impedance coax cable should be used to connect the antennato the LRU. To increase the system performance, a low-attenuation,double-shield coax cable is recommended.Prior to using the antenna, especially after assembly, a VSWR checkshould be done, including the coax cable. The maximum VSWR withinthe bandwidth of interest should be less than 1.7:1 to work in goodconditions.• Specifications• Type: Wideband 7-Element Yagi (Sercel P/N: 07-820070-001).• Frequency: 215 to 240 MHz.• Power Gain: 10.5 dBi, Center frequency.• VSWR: 1.6:1 Max.1.3:1 Center frequency. • Front-to-back Ratio: 20.45 dB, Center frequency• 3-dB beamwidth: E = 48 degrees.H = 57 degrees
Antennas1-10 March 2002• Feed Impedance: 50 ohm.• Connector type Type UHF.• Antenna Boom length: 1.9 m (75").• Longest Element: 68 cm (26.772").• Shortest Element: 48 cm (18.898'').• Weight: 900 g (2 lb).• Maximum mast OD: 5 cm (2").
CABLE PERFORMANCES(Typical @ 2 ms sample rate and 25°C)Maximum number of FDU's per LRU :- 120 with up to 30 m interval - 96 with up to 55 m interval- 80 with up to 75 m intervalMaximum number of FDU's between LRU's or between LRUand LAU :- 60 with up to 30 m interval - 48 with up to 55 m interval- 40 with up to 75 m intervalPHYSICALMaterial AluminiumDimension and Weights Size380x380x225 mm (14.9x14.9x8.8 in)Weigths 12.6 kg (27.8 lbs)PowerOperating Power Voltage10.5 to 15 VDC, 2 batteryconnectors, to allowuninterrupted operation duringbattery replacementPower consumptionMaster : 23 WSlave : 80 W when retrievingSleep : 1,2 WOperating Temperatures-40°C to 70°CStorage Temperatures-40°C to 70°CWater Depth 1.5 m(*) the number of channels increases proportionally with the ratio : (shot cycle time) / (acquisition time).RADIO PERFORMANCESRadio link between LRU’s (Typical propagation condition, bit error rate better than 10-6,8 m (26 feet) antenna mast, Yagi type antenna)- 16 km (10 miles) up to 240 Channels (*) @2ms samplerate real time retrieval.- 24 km (15 miles) up to 60 Channels (*) @2ms samplerate real time retrieval.RF Characteristics :RF Frequencies USA use : limited to 216 MHz to218 MHz and 219 MHz to 220 MHzCanadian use : limited to 217 MHz to218 MHz and 219 MHz to 220 MHzOther countries : in respect with localregulationOverall capability : 215 MHz to 250 MHzRF Output Power RF power management ; 6W nominalRF OutputImpedance 50 ΩFCC EmissionDesignators 200K0D1D and 800K0D1DGENERALRadio Functions Communication with another LRUfor data transmission with errorrecovery and temporary storageCable Functions full LAUX capabilitiesTests capabilities Power supplyRadio data transmissionCable data transmissionField tests Instrument testsAntenna spectrum monitoring capabilityRadio setup Pocket terminal connectioncapabilityMemory 4Mb local buffer for non-real timetransmission modeInterval betweenLRU's or LRU and LAUXon transverse Up to 300 m with ST cableUp to 250 m with WPSRUp to 400 m with WPSRLRLRU Specifications

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