Nortel Networks 411-2021-111 manual Stsr cell site configuration, Control Channel redundancy

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3-8Cell Site Layouts

120° STSR cell site configuration

The Metrocell in a 120° STSR configuration uses at least two equipment frames, one CE Frame and one RF frame (see Figure 3-4). Each TRU/DPA Shelf and its associated ATC on the RF frame support one of the three sectors. With only one RF frame, the maximum number of Voice Channels (VCH) supported by each sector is six since two of the eight TRUs on the TRU shelf have to be assigned as the Control Channel (CCH) and the Locate Channel Receiver (LCR). A 120° STSR Metrocell with one RF Frame requires six antennas; one TX/RX antenna and one RX only antenna for each sector (see Figure 3-6). As traffic grows, two additional RF frames can be added to accommodate more VCHs (see Figure 3-5).

A 120° STSR Metrocell with three RF Frames requires six antennas. It may be three TX/RX antennas and three RX only antennas or six TX/RX antennas depending on the number of channels in each RF Frame. An RF Frame with 20 channels or less in one sector requires one duplexer in the RF Frame and one TX/RX antennas for that sector. The outputs of the three combiners are combined through one phasing transformer (located at ATC 2) and connected to Duplexer position 2 in that RF Frame. The output of the duplexer is then connected to the main TX/RX Antenna of that sector).

An RF Frame with 21 channels or more in one sector requires two duplexers in the RF Frame and two TX/RX antennas for that sector. The outputs of ATC 1 and ATC 2 are combined through one phasing transformer (located at ATC

2)and connected to Duplexer position 2 in that RF Frame. The output of the duplexer is then connected to main TX/RX Antenna of that sector. The output of ATC 3 is connected to Duplexer position 3 and then to the diversity TX/RX Antenna of that sector. This arrangement is used to meet the requirement of a minimum of 21 channel spacing (630 kHz) between the channels in one RF

Frame. Figure 3-5 shows the frame layout and Figure 3-7 shows the block diagram of a 120° STSR Metrocell with three RF Frames.

Control Channel redundancy

Control Channel (CCH) redundancy is commonly provided with a Locate Channel Receiver (LCR) backup. With one RF Frame, the CCH of each sector is assigned to position 1 on the TRU/DPA Shelf of that sector and the LCR is assigned to position 4 on the same shelf. With three RF Frames, the CCH of each sector is assigned to position 1 on TRU/DPA Shelf 1 of that sector and the LCR is assigned to position 4 on the same shelf. This arrangement will have the CCH and the LCR supplied on a different DC power feed and a TCM card. No RF coaxial switch is required since the cavity of the LCR position on the ATC will tune to the CCH frequency when backup is required.

411-2021-111 Standard 01.01 June 1996

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Contents
DualMode Metrocell Page Page Publication history JuneContents Datafilling a Metro Cell Site Power and Grounding RequirementsCell Site Components AppendicesBlock diagram of a 120 Stsr Metrocell using one RF Frame List of tablesPage About this document Intended audience for this publicationHow this publication is organized Applicability of this publicationBand List of termsCarrier RF DBW CellDBm DuplexerIsolation FilterForward path LossDqpsk ModulationOmni Return lossSector Signal RFSectorization Stsr Introduction Northern Telecoms DualMode MetrocellSystem architecture of a DualMode Metrocell Digital ready cellular productBasic components of a DualMode Metrocell Universal CE Frame Metro RF FrameChannel assignment for 800 MHz cellular systems 800 MHz cellular bandChannel assignment Band a 416 channels Band B 416 channels Introduction 6Introduction Standard 01.01 June Omni configuration Cell Site ConfigurationsOverview Sectorized configuration Omni N=7 frequency reuse plan120 N=7 sectorized frequency reuse plan 60 N=4 sectorized frequency reuse plan Omni cell site configuration Cell Site LayoutsControl Channel redundancy RF FrameCell Site Layouts 4Cell Site Layouts Transmit cabling TRU/DPA6Cell Site Layouts No. Receive cablingComponent requirement Frames TRUs ATCsStsr cell site configuration CE Frame Block diagram of a 120 Stsr Metrocell using one RF Frame RF FrameBlock diagram of a 120 Stsr Metrocell using three RF Frames 12Cell Site Layouts DPA 9 Port1 CCH ATC3 Port DPA 10 Port1 14Cell Site Layouts TRU/DPA ATC 16Cell Site Layouts Sector Sector Y Sector ZSector Y TX/RX, 3 RX Sector U Stsr cell site connectionControl Channel Locate Channel Receiver Sector Sector W22Cell Site Layouts Block diagram of a 60 Stsr Metrocell with two RF Frames 24Cell Site Layouts Block diagram of a 60 Stsr Metrocell with four RF Frames 26Cell Site Layouts Transmit cabling 28Cell Site Layouts TRU/DPA 30Cell Site Layouts Port2 ATC3 Port DPA Port1 RF Frame 32Cell Site Layouts Receive cabling 34Cell Site Layouts Sector Y 36Cell Site Layouts Component requirement 38Cell Site Layouts Standard 01.01 June Cell Site Components Major components of a DualMode Metrocell DescriptionNTAX98AA FRU Customer Service Operations 4Cell Site Components Standard 01.01 June Power and Grounding Requirements Safety requirementsPower and grounding requirements Power and Grounding Requirements 4Power and Grounding Requirements Frame power distribution Power distribution for the CE and RF Frames in a MetrocellSystem power protection Grounding UL/CSA approvalCEC par DC coupled signals Cable Identification 10Power and Grounding Requirements Standard 01.01 June Datafilling a Metro Cell Site Datafill OverviewTable Clli Table AcualmMetro RF Frame ATC Alarm PointsCavities Fan Pwr Hsmo +27V a Table VCHINV, CCHINV, Lcrinv Rip Connector J206Port # Frequency Assignment Example Example of Metro TRU datafillExample of Metro ICRM/TRU hardwire configuration Icrm8Datafilling a Metro Cell Site Standard 01.01 June System Configuration Appendix a DualMode Metrocell Cell Site SpecificationsRadio Frequency Alarms Audio InterfacePower Distribution Requirements DC Power RequirementsMechanical Packaging EnvironmentalRadiated Emissions Regulatory Electromagnetic EmissionsTelecom Compliance Product Safety Appendix B Frequency Plans =7 Frequency plan Band a=7 Frequency plan Band B =4 Frequency plan Band a =4 Frequency plan Band B10Frequency Plans Standard 01.01 June Page Cell Site Description
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