CDMA Principle and Measurement

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1 CDMA Principle and Measurement Concepts of CDMA CDMA Key Technologies CDMA Air Interface CDMA Measurement Basic Agilent Restricted Page 1

2 Cellular Access Methods Power Time Power Time FDMA Frequency Power Time CDMA Frequency TDMA Frequency Agilent Restricted Page 2

3 CDMA is Also Full Duplex Amplitude US Cellular Channel 384 Reverse Link Forward Link AMPS 45 MHz Frequency Amplitude MHz MHz Reverse Link Forward Link CDMA 45 MHz Frequency MHz MHz Agilent Restricted Page 3

4 Cellular Frequency Reuse Patterns FDMA Reuse CDMA Reuse Agilent Restricted Page 4

5 CDMA Capacity Gains Capacity = CDMA = (1,230,000) (9,600) (Chan BW) (Data Rate) (1) (E b /I 0 ) (1) (V af ) (Fr) (1) (5.01) (1) (.40) (0.67) Processing Gain CDMA = 42 calls (Using 1.5 MHz BW) AMPS = 1.5 MHz 30 khz = 50 Channels Capacity = 50 Channels 7 (1/7 Frequency Reuse) AMPS = 7 calls (Using 1.5 MHz BW) Agilent Restricted Page 5

6 The CDMA Concept 10 khz BW 1.23 MHz BW 1.23 MHz BW 10 khz BW 0 CDMA Transmitter f c f c CDMA Receiver 0 Baseband Data Encoding & Interleaving Walsh Code Spreading Walsh Code Correlator Decode & De- Interleaving Baseband Data 9.6 kbps 19.2 kbps kbps kbps 19.2 kbps 9.6 kbps -113 dbm/1.23 MHz Spurious Signals 1.23 MHz BW 1.23 MHz BW f c f c f c f c Background Noise External Interference Other Cell Interference Other User Noise Interference Sources Agilent Restricted Page 6

7 CDMA Paradigm Shift Multiple Users on One Frequency Analog/TDMA Try to Prevent Multiple Users Interference Channel is Defined by Code Analog Systems Defined Channels by Frequency Capacity Limit is Soft Allows Degrading Voice Quality to Temporarily Increase Capacity Reduce Surrounding Cell Capacity to Increase a Cell's Capacity Analog Analog CDMA CDMA Agilent Restricted Page 7

8 CDMA Principle and Measurement Concepts of CDMA CDMA Key Technologies CDMA Air Interface CDMA Measurement Basic Agilent Restricted Page 8

9 Walsh Codes W = 2n W W n W W n n n W = W = W = Agilent Restricted Page 9

10 Walsh Code Tree Agilent Restricted Page 10

11 Walsh Coding Example Agilent Restricted Page 11

12 Walsh Decoding Example Agilent Restricted Page 12

13 Three users condition Agilent Restricted Page 13

Efficient Searching Finding the Desired Code Becomes

14 Synchronization All Direct Sequence, Spread Spectrum Systems Should be Accurately Synchronized for Efficient Searching Finding the Desired Code Becomes Difficult Without Synchronization Agilent Restricted Page 14

15 What if Walsh Codes are Not Time Aligned? Channel A +1 Walsh Encoded Voice Data -1 Original Time Delayed Channel B Walsh Encoded Voice Data Sum of A & B Walsh Encoded Data Streams Multiply Summed Data with Desired Walsh Code x = = Original Data Was 0 (-1), We Have Interference Now! Agilent Restricted Page 15

16 CDMA System Time How Does CDMA Achieve Synchronization for Efficient Searching? Use GPS Satellite System Base Stations Use GPS Time via Satellite Receivers as a Common Time Reference GPS Clock Drives the Long Code Generator Agilent Restricted Page 16

17 The Rake Receiver Amplitude Time Frequency Agilent Restricted Page 17

18 Rake Receiver Design Antenna T 0 T 1 T 2 T 3 T 4 Delay Taps W 0 W 1 W 2 W 3 W 4 Tap Weights + Output Agilent Restricted Page 18

19 Power Control Basic CDMA interference limited. Near-Far problem. Agilent Restricted Page 19

20 Reverse Link Power Control Maximum System Capacity is Achieved if: All Mobiles are Powered Controlled to the Minimum Power for Acceptable Signal Quality As a result, all Mobiles are Received at About Equal Power at the Base Station Independent of Their Location There are Two Types of Reverse Control: Open Loop Power Control Closed Loop Power Control Open & Closed Loop Power Control are Always Both Active! Agilent Restricted Page 20

21 Open Loop Power Control Assumes Loss is Similar on Forward and Reverse Paths Receive Power+Transmit Power = -73 All powers in dbm Example: For a Received Power of -85 dbm Transmit Power = (-73) -(-85) Transmit Power = +12 dbm Provides an Estimate of Reverse TX Power for Given Propagation Conditions Agilent Restricted Page 21

22 Closed Loop Power Control Directed by Base Station Updated Every 1.25 msec Commands Mobile to Change TX Power in +/-1 db Step Size Fine Tunes Open Loop Power Estimate Power Control Bits are "Punctured" over the Encoded Voice Data Puncture Period is two 19.2 kbps Symbol Periods = usec Agilent Restricted Page 22

23 CDMA Variable Rate Speech Coder DSP Analyzes 20 Millisecond Blocks of Speech for Activity Selects Encoding Rate Based On Activity: High Activity: Full Data Rate Encoding (9600 bps) Some Activity: Half Data Rate Encoding (4800 bps) Low Activity: Quarter Rate Encoding (2400 bps) No Activity: 1/8 Data Rate Encoding (1200 bps) How Does This Improve Capacity? Mobile Transmits in Bursts of 1.25 ms System Capacity Increases by 1/V af Agilent Restricted Page 23

24 Mobile Power Bursting Each Frame is Divided Into 16 Power Control Groups Each Power Control Group Contains 1536 Chips (represents 12 encoded voice bits) Average Power Is Lowered 3dB for Each Lower Data Rate CDMA Frame = 20 ms Full Rate Half Rate Quarter Rate Eighth Rate Agilent Restricted Page 24

25 4 Soft handover Unlike GSM hard handover Cdmamake soft handover for BS with same frequency Soft handover, more effective and reliable BS Frequency f1 BS Frequency f1 Agilent Restricted Page 25

26 CDMA Principle and Measurement Concepts of CDMA CDMA Key Technologies CDMA Air Interface CDMA Measurement Basic Agilent Restricted Page 26

27 Forward Link Traffic Channel Physical Layer Vocoded Speech data 20 msec blocks Convolutional Encoder 9.6 kbps 14.4 kbps 1/2 rate 3/4 rate 19.2 kbps 19.2 kbps Interleaver Long Code Long Code Scrambling 19.2 kbps 19.2 kbps Power Control Puncturing 19.2 kbps 800 bps P.C. MUX 800 bps 19.2 kbps Walsh Cover Mbps Walsh Code Generator Mbps Mbps I Short Code FIR Short Code Scrambler FIR Q Short Code Mbps I Q Agilent Restricted Page 27

28 Why Spread Again with the Short Sequence? Provides a Cover to Hide the 64 Walsh Codes Each Base Station is Assigned A Time Offset in its Short Sequences Walsh Coded Data at Mbps Mbps I Channel Short Sequence Code Generator Time Offsets Allow Mobiles to Distinguish Between Adjacent Cells Also Allows Reuse of All Walsh Codes in Each Cell Mbps To I/Q Modulator Q Channel Short Sequence Code Generator Agilent Restricted Page 28

Auto-Correlation Is a Comparison of a Signal Against Itself Good Pseudo-Random Patterns Have: Strong Correlation at Zero Time Offset Weak Correlation at Other

29 Auto-Correlation Is a Comparison of a Signal Against Itself Good Pseudo-Random Patterns Have: Strong Correlation at Zero Time Offset Weak Correlation at Other Time Offsets Pseudo-Random Sequence chip Auto-Correlation Versus Time Offset chip offset Agilent Restricted Page 29

30 Short Code Correlation Short Codes Are Designed to Have: Strong Auto-Correlation at Zero Time Offset Weak Auto-Correlation at Other Offsets Good Auto-Correlation In Very Poor Signal-to-Noise Ratio Environments Allows Fast Acquisition in Real World Environment Auto-Correlation Versus Time Offset with 17 db Noise Added chip offset Agilent Restricted Page 30

31 Forward Link Channel Format Walsh Code 0 Pilot Channel Sync Channel All 0's 4.8 kbps kbps Walsh Code kbps Walsh Codes 1 to 7 Convert to I/Q & Short Code Spreading Convert to I/Q & Short Code Spreading I Data Q Data I Data Q Data FIR LP Filter & D/A Conversion FIR LP Filter & D/A Conversion I Paging Channels 1 up to 7 Channels Traffic Channels 1 up to 55 Channels 19.2 kbps kbps Convert to I/Q & Short Code Spreading Walsh Codes 8-31, kbps kbps Convert to I/Q & Short Code Spreading I Data Q Data I Data Q Data FIR LP Filter & D/A Conversion FIR LP Filter & D/A Conversion Q Agilent Restricted Page 31

32 Pilot Channel Physical Layer l Uses Walsh Code 0: 3All 64 bits are 0 Walsh Modulator Mbps I Short Code l All Data into Walsh Modulator is 0 l Output of Walsh Modulator is Therefore all 0's l Pilot Channel is just the Short Codes All 0 input Mbps Walsh Code Generator Walsh Code Mbps FIR Short Code Scrambler FIR Q Short Code Mbps I Q Agilent Restricted Page 32

33 Sync Channel Physical Layer Sync Channel Message Data Convolutional Encoder 1.2 kbps 1/2 rate 2.4 kbps Symbol Repetition 2x 4.8 kbps Interleaver 4.8 kbps Walsh 32 Cover Mbps Walsh Code Generator Mbps Mbps I Short Code FIR Short Code Scrambler FIR Q Short Code Mbps I Q Agilent Restricted Page 33

34 Paging Channel Physical Layer Paging Channel Message Data Convolutional Symbol Encoder Repetition 4.8 kbps 1/2 rate 9.6 kbps 2x 19.2 kbps Interleaver Paging Channel Long Code Long Code Scrambling 19.2 kbps 19.2 kbps 19.2 kbps Walsh 1 to 7 Cover Mbps Walsh Code Generator Mbps Mbps I Short Code FIR Short Code Scrambler FIR Q Short Code Mbps I Q Agilent Restricted Page 34

35 Reverse Link Traffic Channel Physical Layer Vocoded Speech Data 9.6 kbps 20 msec blocks Convolutional Encoder Interleaver 1/3 rate 14.4 kbps 1/2 rate 28.8 kbps 28.8 kbps 28.8 kbps 64-ary Modulator 1 of 64 Walsh Codes Walsh Code 63 Walsh Code 62 Walsh Code 61 Walsh Code 2 Walsh Code 1 Walsh Code 0 Long Code kbps Mbps Long Code Modulator Mbps Mbps I Short Code Short Code Scrambler t/2 1/2 Chip Delay FIR FIR Q Short Code Mbps I Q Agilent Restricted Page 35

36 64-ary Modulation Every 6 Encoded Voice Data Bits Points to One of the 64 Walsh Codes Spreads Data From 28.8 kbps to kbps: (28.8 kbps * 64 bits)/ 6 bits = kbps) Is Not the Channelization for the Reverse Link 28.8 kbps Walsh Code 63 Walsh Code 62 Walsh Code 61 Walsh Code 2 Walsh Code 1 Walsh Code kbps Agilent Restricted Page 36

37 Why Aren't Walsh Codes Used for Reverse Channelization? All Walsh Codes Arrive Together in Time to All Mobiles From the Base Station However, Transmissions from Mobiles DO NOT Arrive at the Same Time at the Base Station Agilent Restricted Page 37

Reverse Channel Long Code Spreading Long Code Spreading Provides Unique Mobile Channelization Walsh Modulated Voice Data 307.

38 Reverse Channel Long Code Spreading Long Code Spreading Provides Unique Mobile Channelization Walsh Modulated Voice Data kbps XOR Mbps Mobiles are Uncorrelated but not Orthogonal with Each Other Long Code Generator Mbps Agilent Restricted Page 38

39 Reverse Channel Short Sequence Spreading Same PN Short Codes Are Used by Mobiles Short Sequence Spreading Aids Base Station Signal Acquisition Extra 1/2 Chip Delay is Inserted into Q Path to Produce OQPSK Modulation to Simplify Power Amplifier Design Mbps Mbps I Short Code t/2 FIR Q 1/2 Chip Delay Q Short Code Mbps FIR I Agilent Restricted Page 39

40 OQPSK Modulation QPSK Makes one Symbol Change Every Period I OQPSK Makes two Symbol Changes Every Period if both I and Q Data Changes Q Example Symbol Pattern is: 00, 10, 01, I Q Agilent Restricted Page 40

41 CDMA Modulation Formats Base Station Pilot Channel TX Q Mobile Station TX Q I I Filtered QPSK Filtered Offset QPSK Agilent Restricted Page 41

42 Channelization Summary Function 9.6 kbps Convolutional Encoder 14.4 kbps ConvolutionalEncoder Forward Link {Base to Mobile} 1/2 Rate {9600 in out} 3/4 Rate {14400 in out} Reverse Link {Mobile to Base} 1/3 Rate {9600 in out} 1/2 Rate {14400 in out} Walsh Coding Channelization 64-ary Modulation Long Code Voice Privacy Channelization Spreading Short Code Spreading Base Station Identification Aid Base Station Searching Agilent Restricted Page 42

43 CDMA Service Options Service Options Are: 1-Voice Using 9600 bps IS-96-A Vocoder 2-Rate Set 1 Loopback (9600 bps) 3-Voice Using 9600 bps (EVRC) 4-Asynchronous Data Service (circuit switched) 5-Group 3 Fax 6-Short Message Service (9600 bps) 7-Internet Standard PPP Packet Data 8-CDPD Over PPP Packet Data 9-Rate Set 2 Loopback (14400 bps) 14-Short Message Service (14400 bps) 32,768-Voice Using bps (CDG) Agilent Restricted Page 43

44 Ten Minutes in the Life of a CDMA Mobile Phone Turn-on System Access Travel Idle State Hand-Off Initiate Call System Access Continue Travel Initiate Soft Handoff Terminate Soft Handoff End Call Agilent Restricted Page 44

45 CDMA Turn On Process Find All Receivable Pilot Signals Choose Strongest One Establish Frequency and PN Time Reference (Base Station I.D.) Demodulate Sync Channel Establish System Time Determine Paging Channel Long Code Mask Agilent Restricted Page 45

Sync Channel Message Contains the Following Data: Base Station Protocol Revision Min Protocol Revision Supported SID, NID of Cellular System Pilot PN Offset of Base Station Long Code

46 Sync Channel Message Contains the Following Data: Base Station Protocol Revision Min Protocol Revision Supported SID, NID of Cellular System Pilot PN Offset of Base Station Long Code State System Time Leap Seconds From Start of System Time Local Time Offset from System Time Daylight Savings Time Flag Paging Channel Data Rate Channel Number SYNC Agilent Restricted Page 46

47 Read the Paging Channel Demodulate the Paging Channel: Use Long Code Mask Derived from the Pilot PN Offset Given in Sync Channel Message Decode Messages Register, if Required by Base Station Monitor Paging Channel Paging Agilent Restricted Page 47

48 CDMA Idle State Handoff No Call In Progress Mobile Listens to New Cell Move Registration Location if Entering a New Zone Agilent Restricted Page 48

49 CDMA Call Completion Base Answers Access Probe using the Channel Assignment Message Mobile Goes to A Traffic Channel Based on the Channel Assignment Message Information Base Station Begins to Transmit and Receive Traffic Channel Agilent Restricted Page 50

50 CDMA Soft Handoff Initiation Mobile Finds Second Pilot of Sufficient Power (exceeds T_add Threshold) Mobile Sends Pilot Strength Message to First Base Station Base Station Notifies MTSO MTSO Requests New Walsh Assignment from Second Base Station If Available, New Walsh Channel Info is Relayed to First Base Station Agilent Restricted Page 51

51 CDMA Soft Handoff Completion First Base Station Orders Soft Handoff with new Walsh Assignment MTSO Sends Land Link to Second Base Station Mobile Receives Power from Two Base Stations MTSO Chooses Better Quality Frame Every 20 Milliseconds Agilent Restricted Page 52

52 Ending CDMA Soft Handoff First BS Pilot Power Goes Low at Mobile Station (drops below T_drop) Mobile Sends Pilot Strength Message First Base Station Stops Transmitting and Frees up Channel Traffic Channel Continues on Base Station Two Agilent Restricted Page 53

53 CDMA End of Call Mobile or Land Initiated Mobile and Base Stop Transmission Land Connection Broken Agilent Restricted Page 54

54 IS-2000 Terms & Definitions Chip Is the period of a data bit at the final spreading rate SR - Spreading Rate Defines the final spreading rate in terms of Mcps. So a Mcps system is called a SR3 system. RC - Radio Configuration Defines the physical channel configuration based upon a base channel data rate. RCs contain rates derived from their base rate. For example, RC3 is based on 9.6 kbps and includes 1.5, 2.7, 4.8, 9.6, 19.2, 38.4, 76.8, 153.6, and kbps. RCs are coupled to specific Spreading Rates Agilent Restricted Page 55

55 IS-2000 SR1 Is an Improved TIA/EIA-95-B Narrowband System Occupies the Same 1.23 MHz Bandwidth as TIA/EIA-95-B Forward Link: Adds Fast Power Control Quick Paging Channel to Improve Standby Time Uses QPSK Modulation Rather than Dual BPSK to: Use 3/8 Rate ConvolutionalEncoder instead of 3/4 for 14.4 Service (improves error correction) 128 Walsh Codes to Handle More Soft Handoffs for 9.6 service Reverse Link: Uses Pilot Aided BPSK to Allow Coherent Demodulation Uses 1/4 Rate ConvolutionalEncoder Instead of 1/2 or 1/3 Doubles System Capacity Agilent Restricted Page 56

56 SR1 Forward Radio Configurations Radio Configuration 1 -Required Backwards compatible mode with TIA/EIA-95-B Based on 9,600 bps Traffic Radio Configuration 2 Backwards compatible mode with TIA/EIA-95-B Based on 14,400 bps Traffic Radio Configurations 3, 4, and 5 All use new IS-2000 coding for improved capacity RC3 is based on 9,600 bps and goes up to 153,600 bps RC4 is based on 9,600 bps and goes up to 307,200 bps RC5 is based on 14,400 bps and goes up to 230,400 bps Agilent Restricted Page 57

57 CDMA Principle and Measurement Concepts of CDMA CDMA Key Technologies CDMA Air Interface CDMA Measurement Basic Agilent Restricted Page 58

58 CDMA Mobile Testing

59 Base Station Simulator Pilot Channel Walsh Code 0 Sync Channel Walsh Code 32 Paging Channel Walsh Code 1 Traffic Channel Orthogonal Channel Noise Source RF Output Additive White Gaussian Noise Source Agilent Restricted Page 60

60 CDMA Transmitter Tests Frequency Accuracy CDMA Hard Handoff Time Reference Accuracy Waveform Quality (rho) Range of Open Loop Power Control Time Response of Open Loop Power Control Access Probe Output Power Range of Closed Loop Power Control Maximum RF Output Power Minimum Controlled Power Standby and Gated Output Power Conducted TX Spurious Emissions Radiated TX Spurious Emissions Agilent Restricted Page 61

Waveform Quality CDMA Transmitter Figure of Merit: Rho - Power Correlation Coefficient An Expression Giving the Percent of Transmitted Power That Correlates

61 Waveform Quality CDMA Transmitter Figure of Merit: Rho - Power Correlation Coefficient An Expression Giving the Percent of Transmitted Power That Correlates to the Ideal Code Mobiles Must Meet rho of This level of Performance Produces 0.25 db of Increased Interference to Other Users Agilent Restricted Page 62

62 Frequency Accuracy and Static Time Offset Transmitted Carrier Must be Accurate To Within ±300 Hz (PCS ±150Hz) Cannot Be Measured With a Conventional Frequency Counter Derived from rho Measurement Static Time Alignment (Mobile's Transmitted Data Clock) Must Also Be Accurate To ± 1 µs Measurement is Relative to the Pilot Channel's Transmitted Data Clock Agilent Restricted Page 63

63 Open Loop Power Test Verifies Open Loop Power Control Estimate Accuracy Measured Over an 80 db Dynamic Range Measured at: Base -93.5dBm -Mobile +20dBm Base -65 dbm -Mobile -8 dbm Base -25 dbm -Mobile -48 dbm Mobile Should be Accurate Within ±6 db, and Must be Within ±9.5 db Test set must be within 0.2dB uncertainty for all power measurement +20 dbm -50 dbm Agilent Restricted Page 64

Time Response of Open Loop Power Control Measures MS output power response to step change in input power. Method of Measurement: Connect BS to MS. Make a call.

64 Time Response of Open Loop Power Control Measures MS output power response to step change in input power. Method of Measurement: Connect BS to MS. Make a call. Send alternating up/down power control bits. Change BS output power and measure MS output as function of time. Minimum Standard: Output power shall transition according to mask limits. ^ I or -40 dbm -60 dbm -80 dbm 100 ms Time Time (ms) Agilent Restricted Page 65

65 Closed Loop Power Tests Verifies Closed Loop Power Control Range and Linearity Measured Over a ±24 db Dynamic Range Mobile Must Offer at least ±24 db of Closed Loop Power Control Around the Open Loop Power Control Estimate Measured by Send 100 Up and then 100 Down Power Control Bits +24 db -24 db Agilent Restricted Page 66

66 CDMA Power Measurements Maximum Output Power Test Set CDMA Source to -104 dbm/1.23 MHz Set Access Channel Parameters to Produce Full Power Make a Service Option 002, Full Rate Call Measure Power Maximum Power Specifications: Class 1 Mobiles: 1.25 to 6.3 Watts Class 2 Mobiles: 0.5 to 2.5 Watts Class 3 Mobiles: 0.2 to 1.0 Watt Requires the Accurate Measure of a Wideband Signal with High Crest Factor Agilent Restricted Page 67

67 Gated Output Power Power vs. Time Template 6ms 6ms 3 db 20 db 1.25 msec Agilent Restricted Page 68

68 Overview of TX Tests with Agilent 8960 Establish a Service Option 002 Call Using the 8960 Performs TX Tests Using the 8960: Frequency Accuracy Hard Handoff Static Time Reference Waveform Quality Range of Open Loop PC Time response of open loop power control Range of Closed Loop PC Gated output power Max RF Output Power Min RF Output Power Access Probe Output Power Spurious Emissions Agilent Restricted Page 69

69 Receiver Tests Demodulation of Paging Channel in AWGN Demodulation of Forward Traffic Channel in AWGN Demodulation of Forward Traffic Channel in Multi-path Fading Channel Soft Handoff Power Control Bit Tests Receiver Sensitivity and Dynamic Range Single Tone Desensitization Inter-modulation Spurious Response Attenuation Receiver Spurious Emissions Agilent Restricted Page 70

70 What is Frame Error Rate? Every 20 ms of Digitized Speech (9600 bps or less) Constitutes a CDMA Frame When a Frame Cannot be Correctly Decoded, Error Has Occurred a Frame Individual Chip Errors (Over-the-Air) Do Not Significantly Degrade CDMA Performance CDMA Voice Quality is Acceptable with Frame Error Rates up to 3%. Agilent Restricted Page 71

71 Confidence Limit Testing Measuring Frame Error Rates or Message Error Rates Involves Testing Random Errors Confidence Limits Use Statistical Models to Determine if FER or MER Measurements Meet a Target Specification with a Specified Confidence Confidence Limit Testing Results in the Absolute Minimum Test Time Example: Must meet 0.5% FER with 95% Confidence Agilent Restricted Page 72

72 Confidence Limit Curves Measured FER Error 95% Confidence Limit for 0.5% FER 2 Errors 4 Errors 8 Errors 16 Errors PASS 64 Errors 32 Errors 128 Errors 256 Errors 512 Errors Agilent Restricted Page 73

73 Base Station Simulator Configuration for Sensitivity Tests CDMA Sensitivity Dynamic Channels Test Range Test lor -Total Power -104 dbm -25 dbm AWGN OFF OFF PILOT -7.0 db -7.0 db SYNC db db PAGING db db TRAFFIC db db OCNS db db Agilent Restricted Page 74

74 Receiver Sensitivity and Dynamic Range Establish a Service Option 002 Call (Data Loopback Mode) with the CDMA Mobile Cell Power = -104 dbm/ 1.23 MHz Measure FER and verify less than 0.5% with 95% Confidence 0.5% FER Agilent Restricted Page 75

75 Thanks & QA Agilent Restricted Page 76

CH 5. Air Interface of the IS-95A CDMA System

CH 5. Air Interface of the IS-95A CDMA System 1 Contents Summary of IS-95A Physical Layer Parameters Forward Link Structure Pilot, Sync, Paging, and Traffic Channels Channel Coding, Interleaving, Data