Agilent Technologies 8922

17-2

GSM Theory

Introduction

The HP/Agilent 8922 product family is designed to measure and generate signals for the

GSM digital cellular telephone system. The HP/Agilent 8922 is both a signal generator

and a measuring receiver.

This chapter describes GSM system signals that are generated and received by the HP/

Agilent8922. The GSM system is not described in detail due to complexity. This chapter

is intended only to describe the system as it relates to servicing the HP/Agilent 8922,

meaning the need to know the character of the signals generated and received.

Contents

Main Page Repairing the HP/Agilent 8922 Book Organization Page Page 6 Troubleshooting the Power Supply 7 Adjustments and Calibration 8 Assembly and Disassembly Procedures 9 Replacing a Part 10 Service Screen 11 Self-Test Error Messages 12 Module I/O Specications 13 Instrument Block Diagrams 14 Block Diagram Theory of Operation 15 Diagnostics Theory Page Page Page Page 1-3 Localizing the Problem - Flow Chart (Power-Up) Figure 1-1 Localizing the Problem - Flow Chart Localizing the Problem - Flow Chart (Power-Up) See "Power Up Checks", in this Chapter, for details of the steps given in the ow chart below. Power-Up Checks Power-Up Checks If Power-Up Checks FAILED Error Message Numbers Page Page Page Page If Power-Up Happened Correctly If Power-Up Happened Correctly Page Page Page Page Page Page Page Page Running Memory Card or ROM Based Diagnostics Page Page Running Memory Card or ROM Based Diagnostics Selecting Memory Card Diagnostic Test Execution Conditions Loading and Running the Ram Test Loading and Running the Ram Test Loading the RAM Test Page Page Installing and Operating the Software Using the Compatibility Switch for the HP/Agilent 8922F/H or M/S Back Conversion Forward Conversion Page Page Page Using the HP/Agilent 83210A Service Kit Conguring the RF Extender Configuring the RF Extender Page Using the HP/Agilent 83210A Service Kit Extending Modules Extending Modules Making Measurements Page Page Page Page Parallel Bus Parallel Bus Serial Bus Display Display Keyboard Keyboard Page Page Page Page 6-3 Power Cord Verication Continued Over Power Cord Verification Use this diagram to verify that the correct line cord is being used. Table 6-1 Line Cords PlugType Cable Agilent Part Number C DPlug Description Length, inches (mm) Power Cord Verication Page Page Page Page Page Adjustments and Calibration Timebase Adjustments Page Periodic Calibrations Adjustments and Calibration Sum Loop Adjustment Procedure Sum Loop Adjustment Procedure Procedure: First Adjustment Page Page Page Recommended Torque Top and Bottom Cover Removal Top and Bottom Cover Removal SIDE VIEW 8-4 Inside Protective Covers Inside Protective Covers All covers can be removed with a TX-15 screw driver. Screws shown circled only require loosening. 8-5 AF, Digital and RF Assemblies Removal AF, Digital and RF Assemblies Removal Page A1 Front Panel Removal A1 Front Panel Removal 8-8 A1 Front Panel Removal A1 6 7-11 (A1 Mounting Screws) RFI Gaskets A10 Power Supply Regulator Removal A11 Receiver Mixer Removal Page A12 Pulse Attenuator Removal Page A21 GPIB Interface Removal Page A22 Display Removal A22 Display Removal Page A23 Input Section Removal A23 Input Section Removal A24 Attenuator Removal A24 Attenuator Removal A28 Power Supply Removal A28 Power Supply Removal Page Fan Removal Page Transformer Removal Page Assembly Replacements Adjustments after Replacing Assemblies Page 9-4 Table 9-2 Replaceable Parts 9-5 A1 6 7-11 (A1 Mounting Screws) RFI Gaskets 9-6 Table 9-3 Replaceable Parts Page 9-8 Table 9-4 Replaceable Parts Page 9-10 Table 9-5 Replaceable Parts Page 9-12 Table 9-6 Replaceable Parts Page 9-14 Table 9-7 Replaceable Parts Page Page Page 9-18 Table 9-8 Replaceable Parts Page 9-20 Table 9-9 Replaceable Parts 9-21 9-22 Table 9-10 Replaceable Parts Page Page Page 9-26 Table 9-13 Replaceable Parts Page 9-28 Table 9-14 Miscellaneous Replaceable Parts Firmware Upgrades Page Page Page Page Page Page 11-2 Self-Test Error Messages Page Page A2 Audio Analyzer 2 A2 Audio Analyzer 2 A2 Audio Analyzer 2 A3 Audio Analyzer 1 Page Page A4 Modulation Distribution A4 Modulation Distribution A4 Modulation Distribution A5 Premodulation Filter and NSM Page A5 Premodulation Filter and NSM Serial I/O A6 Signaling Source/Analyzer Page A9 Global Test and Demod Page Page Page A11 Receiver Mixer Page A11 Receiver Mixer A13 Output Inputs2 Page A14 Pulse Driver A14 Pulse Driver A15 Reference Hop Control Page Page Page Page A16 Receiver Page Page Page A18 Spectrum Analyzer A18 Spectrum Analyzer A18 Spectrum Analyzer A19 Measurement Page Page Page Page A23 Input (HP/Agilent 8922A.B,E,F,G,H) Only Page Page Page A23 Input (Agilent 8922M/S Only) Page Page A25 Sum Loop Page Page A17, A26 Step Loop A17, A26 Step Loop Page A27 DAC/Upconverter Page A28 Power Supply A28 Power Supply Input A33 Hop Controller Page Page Page Page Instrument Block Diagrams Reading the Pin Numbers Page Page Page Page Technical Discussion Technical Discussion Block Diagram 1 A23 Input A24 High Power Attenuator A17 StepLoop B A11 Receiver Mixer Page A18 Spectrum Aanalyzer A2 Audio Analyzer 2 A3 Audio Analyzer 1 Page Block Diagram 2 A5 Premod Filter and NSM Page A26 Step Loop A Page A12 Pulse Attenuator A23 Input A24 High Power Attenutor Page Block Diagram 3 HP/Agilent 8922B Only Block Diagram 3 HP/Agilent 8922B Only A35 B Reference A36 FIFO/GPIO Page Block Diagram 4 Block Diagram 4 A31 CODEC A32 GSM Controller A34 GSM RTI A35 Protocol Interface (HP/Agilent 8922F/HM/S Option 003 Only) Block Diagram 5 Block Diagram 5 Page Page AF_DIAGS Page RF_DIAGS RF Generator Step Loop Sum Loop Output Section Pulse Attenuator and Drive Input Section RF Analyzer Step Loop Spectrum Analyzer Receiver Page MS_DIAGS GSM and DCS Diagnostic Tests GSM and DCS Diagnostic Tests Interpreting Results Interpreting Results Page Page Page Page Page Page Page Page Page GSM Theory The GSM System The GSM System GSM Theory E-GSM, DCS1800 and PCS1900 Systems E-GSM, DCS1800 and PCS1900 Systems Index-1 Symbols Numerics A Index-2 B Index-3 C D E F Index-4 K L M N Index-5 S T V