Title: 2G and 3G Air Interfaces
12G and 3G Air Interfaces
2Air Interfaces Outline
- Third Generation Terrestrial Radio Systems
- UWC-136
- UTRA
- cdma2000
- TD-CDMA
- DECT
- Other 3G WCDMA Systems
- CDMA I
- CDMA II
- W-CDMA/Japan
- WCDMA/NA
- WIMS W-CDMA
- Some 3G Satellite Radio Systems
- SW-CDMA SW-CTDMA
- ICO Satellite RTT
- Horizons System RTT
- Definitions
- Frequency Division Duplex (FDD)
- Time Division Duplex (TDD)
- Frequency Division Multiple Access (FDMA)
- Time Division Multiple Access (TDMA)
- Code Division Multiple Access (CDMA)
- Second Generation Radio Systems
- US TDMA
- CDMA
- GSM
3Frequency Division Duplex (FDD)
Forward Link Frequency
Reverse Link Frequency
- In FDD Information From the Handset to the Base
Station Is Carried on One Frequency and
Information From the Base Station to the Handset
Is Carried on Another
4Time Division Duplex (TDD)
Reverse Link Time Slot
Forward Link Time Slot
- In TDD Information From the Handset to the Base
Station Is Transmitted at One Time on One
Frequency and Information From the Base Station
to the Handset Is Transmitted at Another Time on
the Same Frequency
5Advantages and Disadvantages of TDD
- Advantages of TDD Over FDD
- More Efficient for Asymmetric Data
- Reverse Link and Forward Link Propagation
Conditions Are Identical - Forward Link Beamforming Can Be Base on Reverse
Link - Less Complex RF Transceiver
- Disadvantages of TDD Over FDD
- More Delay
- Limited Communications Distance
6Frequency Division Multiple Access (FDMA)
- Each User Occupies a Different Frequency Channel
Time
Channel 1
Channel 2
Channel 3
Channel 4
Channel 5
Channel N
Frequency
7Time Division Multiple Access (TDMA)
- Each User Occupies a Time Slot
- TDMA Is Really FDMA With Each Frequency Channel
Divided Into Time Slots
TS3
TS3
TS3
TS3
TS3
TS3
Time
TS2
TS2
TS2
TS2
TS2
TS2
TS1
TS1
TS1
TS1
TS1
TS1
Frequency
8Code Division Multiple Access (CDMA)
- Each User Has a Unique Code
- CDMA Is Really FDMA With Multiple Users,
Identified by Codes, Sharing Each Frequency
Channel
User 1 User 2 User 3 User N
User 1 User 2 User 3 User N
Time
Frequency
9US TDMA
10US TDMA Highlights
- TDMA º Time Division Multiple Access
- Improved Capacity Over AMPS
- Backward Compatible With AMPS
- Incremental Migration From AMPS to D-AMPS
- Use of Same Frequency Band by AMPS and D-AMPS
- Acceptable Voice Quality
- Support of New Services
- Support of Dual Mode (AMPS/TDMA) Phones
- Improved Voice Privacy
- Improved Fraud Control (Use of Authentication)
- US TDMA Carriers
- ATT Wireless (800 and 1800MHz)
- Southwestern Bell Mobile Systems (800 and
1800MHz) - Cellcom of Israel (800MHz)
- Etc.
11Control Channels in D-AMPS
AMPS 800MHz D-AMPS 800/1800MHz
IS-54b Analog control channels Shared with amps
IS-136 Analog Control Channels Amps Digital
Control Channels D-amps
J-STD-009,010,011 Analog Control Channels Shared
With Amps (1800MHz)
12US TDMA Waveform
40ms
30kHz
- 3 Users Per Frequency Channel
- P/4-DQPSK
- Modulation
I
?/4-DQPSK
Q
13US TDMA Specifications
14US TDMA Interesting Features
- IS-136 Versus IS-54
- Digital Control Channels Added for TDMA
- New Set of Frequencies
- Indicator Field Added to Inform MS of Location of
Control Channels - Coded Digital Verification Color Code (CDVCC)
Added to Control Channels - Frequency Reuse Same As AMPS
7/21 Reuse pattern
15GSM
16GSM Highlights
- GSM º Global System for Mobile Communications
- Design Goals for GSM
- One Standard for Europe - Roaming Among Countries
- Open Interfaces - Almost All
- Digital With Frequency Reuse of 4
- Rich Feature Set Similar to ISDN
- Authentication and Voice Privacy
- Smart or SIM Cards
- Air Interface Specifications
- GSM
- DCS-1800
- ANSI J-STD-007 or PCS 1900 Air Interface
Specification for 1.8 to 2.0GHz Frequency Hopping
Time Division Multiple Access (TDMA) for Personal
Communication System
17GSM Physical Channel
TS0
TS1
4.615ms
TS2
TS3
TS4
200kHz
TS5
TS6
TS7
Absolute Frequency Channel Number (AFCN)
18GSM Specifications
19GSM Logical Channels
TCH(FS, HS, F9.6, F4.8, F2.4, H4.8, H2.4)
BCH(BCCH, FCCH, SCH)
CCCH(PCH, AGCH, RACH)
DCCH(SDCCH, SACCH, FACCH)
20cdmaOne
21cdmaOne Highlights
- cdmaOne º Code Division Multiple Access Based on
IS-95 Air Interface Standard - Air Interface Standards
- IS-95 800MHz Standard
- J-STD-008 1900MHz Standard
- All Base Stations Transmit on the Same Frequency
- All Mobile Stations Transmit on the Same
Frequency - Soft Handoff Multiple Base Stations (or Sectors)
Send the Same Signal to a Single Mobile Station - Handsets Have Special Receivers Called Rake
Receivers That Combine Multipath or Multiple
Copies of the Same Signal - Approximately 6x Improvement Per Channel Over
AMPS Capacity
22cdmaOne Channels
Pilot
Sync
Paging
Access
Traffic
1.25MHz
23cdmaOne Specifications
24cdmaOne Soft Handoff
- Example
- Three Base Stations Sending the Same Information
to the Mobile Station - Three Base Stations Receiving the Same
Information From the Mobile Station
25UWC-136
26What is UWC-136?
- Evolution of Todays TDMA (IS-136)
- Universal Wireless Communications (UWC) - 136
UWC-136
IS-136
136
136 HS
27IS-136 and IS-136 Highlights
- 136 TDMA Characteristics
- Based on TIA/EIA IS-136
- FDD
- 30kHz Bandwidth Per Traffic Channel
- Maximum Data Rate ??9.6kbps Using One Timeslot
- Supports Several Methods of Handoff
- Supports IS-641A ACELP Vocoder
- Minimum Required Bandwidth for 7/21 Reuse Is
630kHz by 2 - 136 TDMA Characteristics
- Simultaneous Voice and Data
- 30kHz Bandwidth Per Traffic Channel
- Supports IS-641 and US1 Vocoder
- Maximum User Data Rate ??14.4kbps?using One
Timeslot - Minimum Required Bandwidth for 7/21 Reuse Is
630kHz by 2 - Supports Discontinuous Transmission (DTX)
- Minimum Required Bandwidth for 7/21 Reuse Is
630kHz by 2
28136 HS Highlights
- Supports Mulitband Operation From 500MHz to
2.5GHz - Can Be Deployed in a Minimum of 1MHz of Spectrum
- Coexist With Existing Second Generation Systems
- FDD for 136 HS Outdoor and FDD or TDD for 136 HS
Indoor - 136 HS Services Supported by 136 and 136 Control
Channels - Slow Frequency Hopping Option
- Minimum Data Rate Requirements
- Macrocellular
- Pedestrian (3km/hr) gt?384kbps
- Low Speed Vehicle (?100km/hr) gt?384kbps
- High Speed Vehicle (100-500km/hr) gt?144kbps
- Micrcellular/indoor
- Pedestrian (?3km/hr) gt?2048kbps
- UWC-136 Bandwidth Requirements
- 136 HS Outdoor 200kHz
- 136 HS Indoor 1600kHz
29UWC-136 Specifications
30136 HS Frequency Planning
- Coexistence of 136 HS and 136
- Potential Cell Plan
Guardband
200kHz
30kHz
E1
E2
E3
D7...
D1
D2
D3
D4
D5
D6
31UWC-136HS Forward an Reverse Link Features
- 136 HS Outdoor
- Forward and Reverse Link Power Control on a Time
Slot Basis Via Signaling Messages - Antenna Diversity With Two Receiver Chains and
Antennas - 8-PSK and GMSK Modulation
- 136 HS Indoor
- Forward and Reverse Link Power Control on a Time
Slot Basis Via Signaling Messages - Multiple Antennas or Adaptive Antennas
- B-O-QAM and Q-O-QAM Modulation
- Enhancements
- Inter-cell Interference Suppression Via Adaptive
Array Antennas and Joint Demodulation of
Co-channel Signals - Fast Power Control on Frame by Frame Basis
- Improved Channel Coding Using Optimized
Puncturing, Turbo Codes, Etc.
32UWC-136 Modulation Schemes
136HS Outdoors
136
136
136HS Indoors
?/4-DQPSK
?/4-DQPSK
8-ary PSK
I
I
?/4 -QPSK
GMSK
?/4 -QPSK
B-O-QAM
Q
Q
8-ary PSK
33UTRA
34UTRA Highlights
- UTRA º UMTS Terrestrial Radio Access
- ETSI SMG2 Proposal to ITU
- In the Paired Band (FDD - Frequency Division
Duplex) of UMTS the System Adopts the Radio
Access Technique Formerly Proposed by the W-CDMA
Group - In the Unpaired Band (TDD - Time Division Duplex)
the UMTS System Adopts the Radio Access Technique
Proposed Formerly by the TD-CDMA Group - Variable Spreading Factor (VSF) and Multicodes
Used for Variable Data Rates - Handoff to GSM
35UTRA Multiple Data Rate Support
- Variable Spreading Factor (VSF) in a Code for
Multi-rate Data Services - Multicode Scheme for Higher Data Rate
Pilot
Code 0
Rchip
R/M
PN Code
Spreading Factor
SFmin 8(RL) 16 (FL)
Code 1
Traffic R bps
Rsymbol Max/2j
R/M
Code 2
Variable Spreading Factor
R/M
Code N
Multi-code
36UTRA Inter-Frequency Handoff
- The Downlink Is Slotted So That a Single Mobile
Receiver Can Make Measurements on Other
Frequencies - When a Frame Is Slotted, It Is Transmitted at a
Higher Power to Maintain a Constant Quality (BER
or FER) When the Processing Gain Is Lowered. - When Sending High Data Rate Services Where
Changing the Processing Gain Is Not Possible,
Some Frames Are Compressed With a Lower
Processing Gain for That Frame.
37UTRA FDD Specifications
38UTRA TDD Specifications
39UTRA Key Features
- FDD Mode Requires No Inter-BS Synchronization
- TDD Mode Requires Inter-BS Synchronization
- Forward and Reverse Link Pilots
40cdma2000
41cdma2000 Highlights
- Direct Sequence and Multi-carrier Waveform
Options on Forward Link - Direct Sequence and Multi-carrier Waveforms May
Employ Spatial Diversity - Forward and Reverse Link Fast Power Control
- Auxiliary Pilots Provided for Antenna Array
Applications - 5 and 20 Millisecond Frame Lengths
- Utilize Turbocodes
- Coherent Reverse Link Using a Reverse Link Pilot
- Forward Link Fast Power Control
- Reverse Link Continuous Transmission
- cdmaOne Discontinuous Transmission
- Base Stations Are Synchronized Via GPS
42cdma2000 Services
- Voice
- V1
- V2
- Packet
- P1
- P2
- P3
- Circuit
- C1
- C2
- C3
- Voice and Packet
- VP1
- VP2
- Voice and Circuit
- VC1
- VC2
- Packet and Circuit
- PC1
- PC2
- PC3
- Voice, Packet and Circuit
- VPC1
- VPC2
43cdma2000 Frequency Plan
- Two options for using Bandwidth
- Multi-Carrier (Forward Link Only)
- Direct Sequence
625kHz Guardband
1.25MHz
1.25MHz
1.25MHz
1.25MHz
1.25MHz
1.25MHz
1.25MHz
Multi-Carrier
1.25MHz
1.25MHz
1.25MHz
1.25MHz
1.25MHz
1.25MHz
1.25MHz
Direct Sequence
44cdma2000 Specifications
45cdma2000 Channel Structure
- Two Types of Physical Channels
- Dedicated Physical Channel (DPHCH)
- Common Physical Channel (CPHCH)
DPHCH
CPHCH
F-DAPICH/R-PICH F/R-SCHT F/R-DCCH F/R-FCH
F-PICH F-CAPICH F/R-CCHT
F/R-SCH1 F/R-SCH2
F-PCH F-SYNC F/R-CCCH R-ACH
Shared cdma2000
46cdma2000 - Two Phases
- cdma2000 Phase 1
- 1.25MHz Channel With Enhanced Coding and Signal
Processing (N 1) - Physical Layer Capacity Improvements With Minimal
Modifications to cdma2000 Base Stations - Higher Data Rates Via Improvements in Physical
Layer - Data Capacity Improvements Via Enhanced Medium
Access Control (MAC) Layer Quality of Service
(QoS) Capabilities - cdma2000 Phase II
- Full IMT-2000 Compliance
- Full Packet and Circuit Data Capability up to
2Mbps - Full MAC Layer QoS Capabilities
47TD-SCDMA
48TD-SCDMA Highlights
- TD-SCDMA º Time Division - Synchronous Code
Division Multiple Access - China CWTS Proposal to ITU
- Deployment Areas Will Be Medium and Large Cities
- Compatibility With 2G, Especially GSM in China
- High User Density
- Cell Sizes lt 2km
- Environment
- Indoor
- Outdoor to Indoor
- Pedestrian
49TD-SCDMA Variable Data Rate
- Basic Rate (9.6kbps), to Provide Higher Data
Rate - Aggregate Multiple Time Slots
- Aggregate Multiple Code Channels
- Use an Adaptive TDD Scheme (for Asymmetric Data)
- Use a Higher Order Modulation Scheme (16QAM)
- Use Multiple Frequency Carriers
- To Provide Low Speed Data (for Example, 4.8kbps)
Service, a Simple Bit Repeating Scheme Can Be
Used
50What is SCDMA?
- Synchronous Code Division Multiple Access (SCDMA)
- Definition
- Signals From the Mobiles Will Be Synchronous at
the BS - Advantages
- All CDMA Code Channels Will Be Orthogonal
Reducing Co-channel Interference - Higher Capacity
- Simplified Hardware and Lower Cost
Base Station
51TD-SCDMA Specifications
52TD-SCDMA Time Slot Structure
5ms
1.4MHz
Guard band
- Total 8 Time Slots (TSs) With 16 Channels Per TS
- Walsh Codes Separate Users Within a TS
53DECT
54DECT Highlights
- DECT º Digital Enhanced Cordless
Telecommunications - ETSI Proposal to ITU
- Data Transmission Rates up to 2.88Mbps
- Wireless Relay Stations
- Coexistence of Uncoordinated Installations on the
Same Frequency Bands - Access to Different Systems by the Same Handset
- GSM
- ISDN
- Data Networks
- DECT Authentication Module (DAM)
- 128 Bit User Authentication Key
- Cipher Generated During Authentication
- 64 Bit Cipher Key
55DECT Specifications
56Multi-Carrier TDMA
- Multi-Carrier Time Division Multiple Access
Base Station
Timeslots
Base Station
Frequencies
57DECT
Tx
0-5ms
Tx
5-10ms
Tx
0-5ms
Tx
Rx
Tx
Rx
5-10ms
Rx
1.728MHz
Tx
Tx
- Symmetric Connection
- Asymmetric Connection
58DECT Seamless Hand-off
Base Station
Base Station
0
0
f1
12
12
11
11
f4
23
23
59Other 3G WCDMA Systems - Page One
- CDMA I º Code Division Multiple Access I
- South Korea TTA Proposal to ITU
- Transmission Limitation for Inter-frequency
Handoff - Limit the Data Transmission on the Forward Link
to Find Other Frequencies Without Sacrificing
Link Performance - Synchronous Reverse Link
- Reverse Link Synchronization Using Time Alignment
Command - Synchronous CDMA System
- Synchronous Cells
- Optional Asynchronous Mode Under Progress
- CDMA II º Code Division Multiple Access II
- South Korea TTA Proposal to ITU
- Asynchronous Inter-BS Operation
- W-CDMA/NA º Wideband Code Division Multiple
Access / North America - USA T1P1 Contribution to ITU
- FDD No Inter-BS Synchronization TDD Inter-base
Station Synchronization
60Other 3G WCDMA Systems - Page Two
- W-CDMA/Japan º Wideband Code Division Multiple
Access / Japan - Japan Association of Radio Industries and
Businesses (ARIB) Proposal to ITU - FDD and TDD Modes
- FDD Does Not Require Accurate Inter-base Station
Synchronization - TDD Requires Accurate Inter-base Station
Synchronization - Forward and Reverse Link Pilots
- Forward Link Pilot is a Separate Code for FDD
Mode - Reverse Link Pilot is I/Q Multiplexed for FDD
Mode - Forward and Reverse Link Pilots are Time
Multiplexed for TDD Mode - WIMS-WCDMA º Wireless Multimedia and Messaging
Services (WIMS) W-CDMA - No Inter-BS Synchronization Required
61Other 3G WCDMA Air Interface Specifications-One
62Other 3G WCDMA Air Interface Specifications-Two
63Satellites SW-CDMA SW-CTDMA
64Satellites SW-CDMA SW-CTDMA
- Why WCDMA for Satellites?
- Full Frequency Reuse Easing Resource Allocation
- Softer Handoff
- Suitable for Interference Mitigation (MUD)
- Two European Radio Transceiver Technologies (RTT)
Proposals - SW-CDMA
- For Global Systems (Low Earth Orbit (LEO)/medium
Earth Orbit(MEO)) - Adaptation of the Terrestrial ETSI UTRA/ARIB
W-CDMA Proposals to the Satellite Environment - SW-CTDMA
- For Regional Systems (HEO/GEO)
- Hybrid Solution Found Particularly Attractive for
Regional Systems (HEO/GEO Orbits) - Some Commonality With ETSI UTRA
- Combines CDMA and TDMA Advantages
65SW-CDMA SW-CTDMA Specifications
66Satellites ICO Satellite RTT
67Satellites ICO Satellite RTT
- ICO RTT
- Ten Satellites
- Two Inclined Planes
- Medium-earth Orbit (MEO)
- Transparent Transponders
- Parameters
- Access Scheme FDMA/TDMA
- Channel Spacing 25 kHz
- 6 Slots Per Channel
- RF Channel Rate 18/36 kbps (Depending on Channel
Type) - Convolutional Coding
- 1/3 Rate (for Voice)
- 1/2 Rate (for Data)
68Satellites Horizons System RTT
69Satellites Horizons System RTT
- System Parameters
- TDMA/FDM Multiple Access Scheme
- 200 kHz Channels, Reservation Based Slot
Allocation - Bandwidth Efficient Modulation and Coding
- 16-QAM, Turbo Coding
- Bandwidth on Demand Capability
- ATM-like Cell-switching Protocol
- Use of Standard PC Communication Applications
- Compatible With Industry Standard Modem
Interfaces - Service Compatibility, Roaming With Terrestrial
IMT-2000 - High Power GEO Mobile Satellites for 2002 Service
Laptop (144kbps)