Motorola i860 manual DEN Voice Compression Technology, RF Transmission Bursts

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OVERVIEW: iDEN Voice Compression Technology

algorithms and one digital-signal processor (DSP) to perform voice compression/decompression and RF modulation/demodulation.

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Transmitting 6 of 6 slots continually.

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When turned on, scans for control station, then transmits one slot every six slots.

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Figure 1-2. i DEN TDMA Format

1.2i DEN Voice Compression Technology

Voice is converted into a digital bit stream by sampling the voice signal at a high rate and converting the samples into numbers, which are represented by bits. A sample consists of 8 bits. Approximately 8000 samples per second (64 Kbps) are required to maintain a reasonable quality.

Voice compression reduces the number of bits per second while maintaining the voice at an acceptable quality level. The iDEN system uses a coding technique called Vector Sum Excited Linear Prediction (VSELP) to compress voice to 4.2 or 8.0 Kbps. The compressed voice-data bits modulate the RF signal. The compression rate is based on the type of call (dispatch or interconnect) and the network configuration established by the local service provider.

Adding error-correction bits to the coded-voice bits increases the required RF-transmission bit rate to approximately 7.4 Kbps for the 4.2 Kbps voice coder and 14.8 Kbps for the 8.0 Kbps voice coder.

1.2.1RF Transmission Bursts

All RF transmissions within an iDEN system occur in 15-millisecond blocks called bursts. An

iDEN base station transmits bursts continuously on each RF frequency it uses. Transmission bursts from the stations are synchronized in time by signals received from the global positioning satellite

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Contents Page I860 Manual Revisions Safety and General Information Electro Magnetic Interference Compatibility Medical DevicesAccessory Safety Information Cleaning and Drying ConsiderationsSafety and General Information Model Information Model Numbering SystemModel Specifications General Receiver TransmitterContents Chapter Chapter Field Level Test Modes Procedures Appendix a Ordering Replacement Parts Preface Who Should Use This ManualHow This Manual Is Organized Conventions Used in This Manual Related PublicationsOverview DEN Digital Modulation TechnologySpectrum of i DEN Quad 16QAM DEN Voice Compression Technology RF Transmission BurstsCalling Area Coverage Global Positioning System GPS Section SIM CardsRemoving and Inserting a SIM Card To remove a SIM card Figure To insert a SIM card FigureCOMPONENTS, ICONS, and Indicators Component ViewsDisplay Icons Main Menu IconsAbc d efg d Opqr s Status IconsDEF Call IconsContacts Type Icons Outbox IconsThis page intentionally left blank Power-Up Sequence DISPLAYS, MESSAGES, and AlertsSelf-Test Reset Errors Power-Down SequenceSelf-Test Errors MessagesService Messages Service MessagesMessage Cause Action Tone Low High Freq Cadence When Tone Occurs Alert TonesAlert Tones Alert Tones Mode Cadence Using the Optional Vibrate FunctionVibrator Settings To set unit to vibrate for all callsFrom the main menu, select Settings 2-Way Radio Alert Type This page intentionally left blank Test Equipment Preparing for Basic Level TestingReference Accessories Reference UnitThis page intentionally left blank Customer Care Reset ConditionBasic Level Checks and Self Tests Test ConditionsBasic-Level Test Checklist Basic-Level Test ChecklistPreventive Maintenance To clean the unit approximately 3 minutesShock and pressure test time is approximately 3 minutes Mechanical and Electrical ChecksSIM Card Swap Test SIM card swap test time is approximately 5 minutesLockup Test Accessory Swap TestAccessory swap test time is approximately 5 minutes Lockup test time is approximately 6 minutesBattery connections test time is approximately 5 minutes Battery Connections TestTesting the GPS Receiver To test this functionVoltage Recognition Test Camera TestVoltage recognition test time is approximately 4 minutes Passcode Test TroubleshootingSelf-Test Procedures Passcode test time is approximately 5 minutesProgramming Menu Settings Check Settings check test time is approximately 10 minutesPhone Calls Features Way Radio Options Volume Features PersonalizeSecurity Features From the main menu, select Settings Security SIM PINAdvanced Features From the main menu, select Settings Advanced Headset/SpkerCall Performance Test Call performance test time is approximately 7 minutesThis page intentionally left blank To enter debug mode Basic Level Test Modes and ProceduresEntering Debug Mode Test ModesDisplay Screens Display ScreensName Description Entering Test Mode To enter test modeTest Mode Test Procedures Audio Loopback TestTo perform the audio loopback test test time approx min To perform the matching test test time approx min ESN and Imei Matching TestEngineering Debug Check To monitor the data in the unitSoftware choice 68P80400P73-A Technician Test Procedures Programming the i 860 UnitConnecting the Unit to the RSS Workstation Data Cable Programming SetupCodeplug Repair Procedure Codeplug TroubleshootingTo access the codeplug Help topic in Windows Preparing for Field Level Testing Preparing Equipment for TestingUsing RSS Connecting an i DEN Unit to the R-2660To connect the unit to the R-2660 Coaxial Cable In/Out TypeRF Zone Fields and Values To enter Initial Registration modeOperating the R-2660 Field ValueDisassembling and Reassembling the Unit SIM Card Battery CoverInstall RemoveAntenna Required Tools T-4 Torx bitBack Housing Coin Cell Required Tools Black stickMain Board, Microphone Seal, and Keypad Flip Assembly Remove Flip AssemblyPage Install Page Exploded View and Parts List Component Parts List Component ListDescription Part Number Reference Exploded View This page intentionally left blank Field Level Test Modes and Procedures Field-Level Test Checklist Required Test EquipmentField-Level Test Checklist Done Technical Tests Pass FailSee the Strong Signal Environment section Registration/Call TestSQE Reference Chart SQE TestTX Power Test See Entering Test Mode Press Menu, EditBER Test FailPower-Up Test Keypad Test Audio Test Use this test to check the audio portion of the unitReset Test No reset ResetReset Log Test To perform the reset log testModel Assembly MA Test Mode Test Model Assembly MA Test Mode Test GPS Receiver Use this test on a unit to check functionality of the GPSCamera Test Replacement Parts Ordering Replacement Parts and KitsCustomer Service Domestic OrdersReplacement Kits Table A-2. i 860 Replacement KitsDescription Kit Number Vehicle Power Adapters Recommended Test Equipment and Tools Table A-3. Recommended Test Equipment and ToolsDescription Part Number Table A-5. Recommended Software Recommended Programming EquipmentTable A-4. Recommended Programming Equipment Name Part Number DescriptionThis page intentionally left blank Index BcchQAM RSS Vselp @6880400P73@