Nortel Networks 411-2021-111 manual Modulation, Omni, Dqpsk, Return loss, Reverse path

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xivList of terms

Modulation

The process of placing information on an RF carrier. The modulation technique may involve changing the amplitude, frequency, or phase of the carrier determined by the modulation index.

NES

Non-expanded Spectrum. The frequency spectrum initially assigned to the cellular band. The Non-expanded Spectrum provides 333 channels to each of the two bands, the A-Band and the B-Band.

Omni

An antenna design which permits radiation in essentially all H-Plane azimuths. In cell sites, an Omni configuration means a single set of omni antennas is used for all channels.

π/4 DQPSK

Variation of Differential Quadrature Phase Shift Keying used in D_AMPS IS-54 TDMA for improved spectral characteristics and phase resolution. Permissible phase changes are integral multiples of π/4 radians (45 degrees). π/4 is used to reduce the peak to root mean square ratio requirements for linear PAs.

Return loss

A logarithmic relationship of the incident signal to the reflected signal as expressed, in dB, by the following relationship:

Return Loss = 10 log Pr

Pi

where Pi = incident power in watts Pr = reflected power in watts

The strength of the signal, expressed in dB, reflected by a load back into a transmission line due to impedance mismatch. -14 dB corresponds to a VSWR of 1.5:1.

Reverse path

The path from cellular subscriber terminal to cell site.

RF

Radio Frequency. Electromagnetic energy of the frequency range just above the audible frequencies and extending to visible light.

RIP

Rack Interface Panel. The RIP is the interface between the cell site power supply and the cell site equipment.

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 publication How this publication is organized Applicability of this publicationCarrier RF List of termsBand DBW CellDBm DuplexerIsolation FilterForward path LossDqpsk ModulationOmni Return lossSectorization Signal RFSector 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 Band a 416 channels Band B 416 channels 800 MHz cellular bandChannel assignment for 800 MHz cellular systems Introduction 6Introduction Standard 01.01 June Overview Cell Site ConfigurationsOmni configuration 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 AcualmCavities Fan Pwr Alarm PointsMetro RF Frame ATC Hsmo +27V a Port # Rip Connector J206Table VCHINV, CCHINV, Lcrinv Frequency Assignment Example Example of Metro TRU datafillExample of Metro ICRM/TRU hardwire configuration Icrm8Datafilling a Metro Cell Site Standard 01.01 June Radio Frequency Appendix a DualMode Metrocell Cell Site SpecificationsSystem Configuration Alarms Audio InterfaceMechanical DC Power RequirementsPower Distribution Requirements Packaging EnvironmentalTelecom Compliance Regulatory Electromagnetic EmissionsRadiated Emissions 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