SDR
(Software Defined Radio)
개요
성균관대학교
정보통신공학부
조준동 교수
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목차
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Introduction
System Architecture
Software Algorithm
Radio Frequency
Reconfigurable Architecture
Low Power Design
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Device Mobility Continues to Rise
Nokia Communicator
Palm PDA
with GPS Receiver
Kodak Portable MC3
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Future Mobile Functionality
Purchase tickets (E-commerce)
Guide you in the city (GPS, …)
Give local information on a point of interest (Bluetooth, WLAN)
Sound, video, animation
User determines the amount of details using his
preferences
Receive e-mail, phone calls, voice-mail (GSM, UMTS)
Make reservations for your dinner (WAP)
Take pictures / video clips (Microdrive)
Listening to music (MP3)
Store your power-point presentation (files)
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Gilder’s versus Moore’s law
2x/3-6 months
1M
1000 x
10,000
100
2x/18 months
97
99
01
03
05
07
Greg Papadopoulos, Sun Microsystems
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Future trends of mobile
communications
2000
2010
2020
Mobility
Intelligent
Transport
Systems
vehicle
3G cellular
4G cellular
Advanced
wireless
access
pedestrian
GSM
Wireless
LAN
static
2G
10k
3G
2M
High data rate
High mobility
System roaming
Seamless connections to
broadband networks
4G
50M
Millimeterwave
LAN
156M
HAPS
5G
622M
Data rate
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Commercial Cellular/PCS
Capability Enhancements by
Generation
3G: Greatly enhanced data communications services
Narrowband and wideband multimedia services
Higher spectrum for wideband applications
Macro, micro & pico cells
2G:
Digital voice, messaging &
data services
Fixed wireless loop,
wireless LAN services
Digital cellular & PCS
Macro, micro & pico cells
4G: Very high bit rate 20~50Mbps (or
100Mbps)
Multimedia enhancements
4G
Frequency band: 2.2GHz, 5GHz, 7GHz
요구 BER : VOICE (1e-6), DATA (1e-9)
2004~2008년쯤 4G용 주파수 배정
2007~2010년 사이 서비스가 시작
3G
1G: Mobile telephone
Analog technology
2G
Macro cells
Software Defined Radio Opportunity
1G
SDR Forum
1980
1990
2000
2010
Time
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2020
Information Technology
evolution
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•
•
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Before 80 : Middle Age, Computing Sc. belongs to fiefs (IBM, …), no network
• All proprietary, no flow : All is parchment or proprietary spreadsheet
80s : All is transparent for a computer scientist
• All is file : UNIX (/dev/null, /dev/lpr, ...)
• a file is a set of characters which can be manipulated by C language
85s : All is readable on a desk (or a PC) for anybody
• All is document (no more interoperability & transparency)
95s: All is an available object on the network for communication
• All is document, readable everywhere (HTML page) or executable
everywhere (Java)
• Privilege to information access : kiosk, server
00s : All is a digital, fluid & live stream distributed over networks
• Nomadic user, virtual presence (user or sw/content move), Virtual
Machine & JavaBeans
• Ubiquitous IT (networked planet grid) & Mobile computing
infrastructure (Xeo satellites)
05s : All is program, alive on ad hoc networks
• An entity on the network is a Java Program (Jini Concept)
• Intentional architecture
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Infrastructure of Information System
Infrastructure with QoS, mobility & security
New Services
Mobile Terminals
Network Computers
Multimedia Hyperdocument
Intelligent Routers & Switchers
Configurability
Active & Ad hocNetworks
Mobile/fix, wired/wireless
Extra/Inter/Intranet
Distributed
Multimedia
Data
New Services & Usage
biometric Authentication
Adaptive & multi-modal
Human Interface
Speech recognition
Adaptability & customization
of applications according
terminal configuration &
end-user’s services
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New Services
Interface : XML
Protocol: IP
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Indexation by content
Protection of digital Objects
Navigation, Search engine
information filtering
4G Mobile Communication System
Digital
Broadcasting
Cell
ITS
SDR/Multi-mode
Terminal
4G Network
Micro-Cell
BWA
Macro-Cell
• 20-155Mbps
4G Mobile
• 3,40 GHz band
• Fixed User
• Metropolitan
Area
• Over 2-10Mbps
• 2-10 GHz Band
• Vehicular Environments
• Medium Area
WPN
• 1-155Mbps
Indoor Cordless
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• 2.4,5,60 GHz band
• Fixed/ Slow Mobility
• Small Private Area
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PSTN
ISDN
IP Back bone/
Internet
Future System 요구사항
Small user interface: pen, voice, gesture
Many standards
Real-time processing
Long execution time
Work in a dynamic environment
Quality changes from place to place
Hybrid networking: DECT, GSM, UMTS, WLAN,
Bluetooth
Energy-efficient
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ONE phone for many Standards
SDR forum
- Rapid increase of subscriber
- Multiple standards
(peaceful co-existence)
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(need high spectrum utilization
techniques)
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Wireless Data
Standards
TX
GSM
1800
UMTS
GSM
1800
RX
1800 MHz
UMTS
2100 MHz
802.11
HIPERLAN/1
802.11
HIPERLAN/1
2400 MHz
5200 MHz
Channel Bandwidth
Data Rate
EDGE
UMTS
BT
802.11
HIPERLAN/1
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Two Forces Driving
the Wireless Internet
The cellular industry
• Wide area coverage.
• Global roaming.
• Mobile users at
vehicular speeds.
• Subscription-based.
• Licensed bands.
The wireless LAN industry
• Local coverage.
• No handoff or roaming.
• Fixed users.
• Revenue through equipment sales.
• Unlicensed bands.
The
Wireless
Internet
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Heterogeneous wireless
communication networks
by Havinga, havinga@cs.utwente.nl
There exist many wireless communication
networks
– frequency bands
– requirements on mobility
– transmission speed and quality
• Examples:
– Static: wireless LANs (802.11), Bluetooth,
Radio Local Loop
– Pedestrian: DECT, PHS
– Vehicle: 2/3G cellular, pagers, broadcast
TV/radio
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Future wireless
communication
• Two trends will have major impact
– Wide proliferation of various wireless
access networks
• Each with their own preferred type of
service
• Different quality: data rates, latency,
mobility support, ..
– Software radio technologies
• Programmable radios, Tunable front-ends
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Heterogeneous networks,why?
• Due to roaming the network changed
– e.g. from indoor wireless LAN to outdoor
cellular radio
• There is coverage from multiple wireless
networks
–  Possibility to select the most appropriate
network for a given application, based on for
example
•
•
•
•
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Service classification
User requested QoS parameters
Available network capacity (bandwidth, latency)
Energy consumption needed
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•
Heterogeneous network
architecture
Goal
design a flexible and open architecture suitable for a
variety of different wireless access technologies, for
applications with different QoS demands, and different
protocols.
• Key requirements
–
–
–
–
–
–
–
–
–
–
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Different access technologies (Software Defined Radio)
Heterogeneous network support (use combination of networks)
Mobility management (seamless handover)
Wireless system discovery
Selection of efficient configuration
Simple, scalable, low cost
Energy efficient (always on)
Secure
Compatible/interoperable with existing and future work
Quality of Service support (end-to-end, and local applicable)
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Evolution of the Cell Phone
• Two co-existent 3-G cellular standards:
– Wideband CDMA
• Also called UMTS, UTRA, IMT-2000.
• Standardized by 3GPP.
• Evolution of the GSM backbone.
– cdma2000
• Standardized by 3GPP2.
• Evolved from IS-95 CDMA (cdmaONE).
• Common traits:
– 2 GHz PCS band (licensed).
– Variable asymmetric data rates for multimedia:
• ~144 kbps to vehicles.
• ~ 2 Mbps to fixed locations near base station.
– Software-defined-radio (SDR) implementation.
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Standardization of Wireless
Networks
• Wireless networks are standardized by IEEE.
• Under 802 LAN MAN standards committee.
ISO
OSI
7-layer
model
Application
Presentation
Session
Transport
Network
Logical Link Control
Data Link
Medium Access (MAC)
Physical
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IEEE 802
standards
Physical (PHY)
IEEE 802.11 Wireless LANs
• Key features of MAC:
– Infrastructure or ad-hoc network.
– Coordinated (PCF) or distributed (DCF) operation.
• DCF uses CSMA/CA.
• PHY defines data rate and operating band:
– Infrared at 1 or 2 Mbps.
– RF at 1 or 2 Mbps in using FH or DS 2.4 GHZ ISM
band.
– 802.11b amendment
• 5.5 or 11 Mbps using DS and CCK in 2.4 GHz band.
– 802.11a amendment
• 6-54 Mbps using COFDM in 5-6 GHz U-NII band.
• IEEE 802.11 can also be used for broadband access.
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IEEE 802.16 Wireless MAN
• Working group on broadband wireless access
– Focus on providing access to small/medium business
and residential opportunities.
– Early stages of development.
• Task 1
– PHY for the 10-66 GHz licensed bands.
– LMDS band: 500 Mbps in 28-31 GHz band.
• Task 2
– Coexistence of fixed broadband wireless.
• Task 3
– PHY & MAC for 2-11 GHz MMDS licensed bands.
• Task 4
– Fixed broadband version of 802.11a.
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Bluetooth
• Bluetooth SIG formed in 1998 by Ericsson, Nokia, IBM,
Toshiba, and Intel.
• Design goals:
– Inexpensive: $5 single chip solution.
– Short range: 10 m or less.
– Low data rate: < 720 kbps.
– Peer-to-peer and ad-hoc networking.
– Data (ACL) and voice (SCO) support.
• Technology:
– 2.4 GHz ISM band.
– 79 channels of 1 MHz each.
– Frequency Hopping at 1600 hops/sec.
– Nonorthogonal binary GFSK modulation.
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Bluetooth Profiles
• Hands-free headset.
• Cordless telephone.
• Synchronization of PDA, cell phone,
computer.
• Serial port emulation.
• Wearable computing.
• Wireless LAN access.
• Ad-hoc network.
• Peripherals: Printer, scanner, fax machine.
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IEEE 802.15 Wireless PAN
• Standardization began in 1997 under the Ad Hoc
Wearables Standards Committee.
• Same goals and constraints as Bluetooth:
– 2.4 GHz band, 10 m. range, inexpensive.
• Task 1
– Standard almost identical to Bluetooth.
• Task 2
– Coexistence of wireless LANs and PANs.
• Task 3
– 20 Mbps High-rate PAN similar to Bluetooth 2.
• Task 4
– Low rate 2-200 kbps PAN with extremely low power
consumption for perpetual sensors.
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W-LAN (MS) PHY Layer
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Param eter
Operating
Frequency
Spread Spectrum
Method
Data Rate
GSM 2G Cell
890-915 MHz (RX)
935-960 MHz (TX)
TDMA/FDMA/FDD
W-CDMA 3G Cell
2110 - 2170 (RX)
1920 - 1980 (TX)
CDMA/FDD
W-CTDMA 3G
2110 - 2170 (RX)
1920 - 1980 (TX)
CDMA/TDD
IEEE 802.11 WLAN
2400 - 2483.5 MHz
ISM
FHSS
Bluetooth
2400 - 2483.5 MHz
ISM
None or FHSS
9.6 - 64 kbps
32 kbps -384 kbps
256 kbps -4 Mbps
1 Mbps
2 Mbps
0.7 Mbps
2 Mbps (future)
Hom eRF
2400 - 2483.5 MHz
ISM
FHSS, TDMA or
CSMA/CA
1 Mbps
2 Mbps
Modulation
Method
(Index)
GMSK (BT=0.3)
QPSK data
2-FSK (0.32)
modulation on up
4-FSK (0.16,
and dow n;
optional)
Spreading is QPSK.
SF = 2-16
2-FSK (0.32)
TBD (TBD)
2-FSK
4-FSK (required)
Hop Rate
opt, 21.66 Hz
(1/4.615 ms)
QPSK data
modulation on up
and dow n;
Spreading is QPSK
on up and BPSK on
dow n.
na
na
2.5 Hz
0 / 1600 Hz (max)
50 Hz
224 msec
220 msec
300 msec
25 microsec
Channel
Sw itching Tim e
Rx/Tx Turnaround half duplex
Tim e
Antenna Diversity na
na
Tx RF Pow er
<1W
full duplex
half duplex
19 msec
220 msec
Optional
Optional
Optional
Not Required
1.6W (384 kbps),
0.8W (128 kbps)
0.2W (2 Mbps),
0.1W (0.5 Mbps)
<1W (US)
100 mW (Europe &
Japan)
Rx Sensitivity
-110 dBm
-80 dBm @ 1 Mbps
-75 dBm @ 2 Mbps
Tx Stability
+/- 9 Hz
+/- 2 kHz
+/- 2 kHz
+/- 60 kHz
Tx Spectrum
-30 dBc, 1st Adj Ch -40 dBc, 1st Adj Ch -40 dBc, 1st Adj Ch -40 dBc, 2nd Adj
Shape
-60 dBc, 2nd Adj Ch -60 dBc, 2nd Adj Ch -60 dBc, 2nd Adj Ch Ch
60 dBc, 3rd Adj Ch
Hop Seqnce, # Ch. random, <124
na
na
random, 80
0.001 / 0.100 W
0.1 W (N. America)
-70 dBm @ 1 Mbps
-76 dBm @ 1 Mbps
Pow er
Consum ption
Standby / Max
0.3 - 30 ma
@ 5 vDC
2 ma RX Avg
120 ma TX Avg
fd
fd
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?
?
random, 79 or 23
random, 79 or 23
Wide Frequency bands
System
Frequency bands
Cellular
PDC
CDMA one
PHS
800 MHz
1.5 GHz
1.9 GHz
Wireless LAN
IEEE802.11
MMAC
Altair
2.4 GHz
5.15 ~ 5.25 GHz
19 GHz
Pager
NTT
POCSAG
250 MHz
Cordless phone
Analog
250/400 MHz
SDR의 목적: SW를 사용, 유연한 무선 시스템
(다중서비스,다중밴드, 다중표준, 재구성, 재프로그래밍이 가능한)의 구축
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New Digital Broadcasting
Technologies Europe
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
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DAB, Digital Audio Broadcasting
Designed as a follower of FM stereo system
DQPSK/OFDM, 2k DFT
E.g., 6 high-quality stereo channels in 1.5 MHz BW
Data services
Designed for mobile reception
DVB-T, Terrestrial digital TV transmission system
64-QAM/OFDM, 8k DFT
E.g., 4 normal quality TV channels (MPEG2) in place of a single analog
channel of 7 or 8 MHz
stationary & portable reception, mobile reception under study
DVB-S, Digital satellite TV transmission system
QPSK
much commonality with DVB-T in source and channel coding
DVB-C, Digital Cable TV transmission system
64-QAM
much commonality with DVB-T and DVB-S in source and channel coding
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SDR : Abstract
• All functions, modes, and applications can be
reconfigured by software.
– Flexibility to handle a variety of multimedia
services and standards.
– Adaptability to accommodate environment,
required level of security, and available
resources.
– Automatically set its parameters of operation on
the basis of cost efficiency or requested QoS
• Radio equipment reconfigured by downloadable
software, at any layer of the protocol stack.
– New capability can be added without hardware
changes
• flexible/ reconfigurable hardware platforms
– Configurable-ASIC, DSP, MCU, FPGA
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SDR Forum
- 1996년 MMITS (Modular Multifunction
Information Transfer Systems) Forum으로 출발
- Motorola, Lucent, Harris, Nokia, Ericsson, Siemens,
Alcatel, Orange, Panasonic, Sony, 게이오 대학, 삼성
전자, LG전자 및 ETRI 등과 같은 전세계 유수의 이동
통신 관련 업체, 연구기관, 학교 등이 회원으로 참여
- 산업체로 하여금 SDR은 구현 가능한 기술적인 개념이
라는 점을 인식
- 상용 및 군용 통신 분야의 중요한 문제를 해결하는데
SDR 기술의 잠재력을 인식
- SDR 기술 및 시장 잠재성에 대한 가시적인 분석 자료
를 제공
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SDR Forum 조직도
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S/W로 정의되는 SDR 기능
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Hardware in software-defined radio
terminal
-analog stage contains amplifiers, mixers,
synthesizers, ADCs( analog-to-digital converters),
DACs( digital-to-analog converters)
-With different RF specification such as carrier
frequency, bandwidth, modulation scheme, and
transmission power
-digital stage contains FPGAs, DSPs, CPU, ASICs, and
I/O interfaces functions such as digital up/down
converters, digital filters, and modems.
- ASIC : digital filtering, frequency mixing, signal
generation
- FPGAS (DSPs) : channel codec, speech codec
(It’s reconfigured by replacing program.)
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Softwares in
software-defined radio terminal
-Basic programs : radio function libraries : the sets that
express basic radio functions (contain filter programs for
FPGA, modem programs for DSP, or the hardware control
commands)
- OS and device driver : The OS is run to control overall
operation of system. The device drivers are programs for
each hardware control such as amplifier, a synthesizer,
ADC and a DSP.
- Application program : .
This program prepared for a specific radio
standard, such as GSM, IS-95, or IMT-2000.
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SDR Benefit
• Potential for significant life-cycle cost
reductions
• Uniform communication across
commercial, civil, federal and military
organizations
• Over the air downloads of new features
and services as well as software patches
• Debug is impossible for mobile terminals
after they are sold.
• PC와 같은 Open Modular Architecture
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SDR 요소기술
API 설계: 소프트웨어 모듈간 인터페이스, 하드웨어 모듈간 인터
페이스, 하드웨어와 소프트웨어 모듈간 인터페이스 표준화 작
업
Protocol : GSM2Plus, CDMA, 3GPP, 3GPP2와 같은 프로토콜 중,
공통적인 부분을 도출, 모듈화 하고, 나머지 부분을 software
radio로 지원
SDR 객체 지향 framework : Open System, IDL : interface 정
의, minimum CORBA
Software Download: SDR 장비의 동작을 고치거나 성능 향상을
위해 software를 download
RF Module: 다중 모드 지원을 위해 각 모드를 모두 수용하는 광
대역 또는 멀티 밴드의 특성 필요, RF 소자 설계 기술, 안테나
기술, Wideband ADC and DAC
Baseband DSP Module: 멀티 모드와 software 업그레이드가 가
능한 저전력, 고속 DSP를 이용 구현, 표준화된 HW/SW
interface
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SDR-processing requirements
for Mobile Communications (GSM)
Modem w/ basic equalizer
2 MFLOPS for CDMA sector
2.5 MFLOPS for a wideband CDMA
4 MFLOPS for a G4
Requires high performance devices s.t
PowerPC G4
PowerPC with Altivec CPUs
TMS320-C6x
SHARC/Tiger-SHARC DSPs
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SDR 기술진화 단계 및 특징
Digital
Radio
SDR
SWR
정의
정의된 소자들
을 사용 안테
나와 입출력장
치 사이에 정
보 디지탈화
광대역 필터와
LNA/PA, Down/up
converter를 안테나와
입출력 장치 사이에 구
성하여 디지털화
고속 DSP를 이용하
여 무선통신에 필요
한 모든 과정을 SW
변경에 의하여 처리
하기 위해 안테나 단
에서 디지털화
특징
특정 목적을
위해 신호처리
가 이루어 짐.
새로운 기능
추가를 위해
HW 교체
유연하고 재구성가능한
DSP 사용 시스템 제조
후 SW 변경에 의해 기
능 변경
광대역 필터를 이용
수신된 정보를 직법
디지탈화 단일 공ㄷ
통 HW 플랫폼에 응
용 s/w의 무선 다운
로드로 서비스 변경
김지연 ( ETRI SDR 연구팀)
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SDR 단말기의 프로토콜 구성요소
Micro controller : 실시간 처리가 필요한 에러 검출코
드 생성 및 검출 기능 등을 하드웨어 논리를 이용하여
지원하고 이벤트가 자주 발생하지 않는 사건은
firmware를 이용하여 처리한다.
RTOS : 통신 프로토콜 소프트웨어에서 필요로 하는 기
본 기능을 라이브러리로 제공하며 프로세스 상호간의 통
신을 지원한다.
Protocol Stack : GSM2Plus, CDMA, 3GPP, 3GPP2,
옥내 통신의 무선 접속 인터페이스 프로토콜 들을 계
층별로 구현하고 표준인터페이스를 지원한다.
신호 응용 서비스 : 제어영역의 다양한 멀티미디어 신호
처리를 담당한다.
마이크로 프로세서 : 응용 프로토콜을 지원한다.
Middle ware : Client/server 환경의 최적해법을 지원
한다.사용자 영역의 멀티미디어 트래픽 응용 서비스를
지원한다.
39
© ICU 전파교육연구센터 2003
Distributed Layered Virtual Machine
Wa veform Personal ities
Mapping, Data Bases,
Common Applications Location
Awareness, ...
Map Update Agent
Communications
Encapsulated Waveforms,
SINCGARS Bridging
Applications
Bridging, Location Estimation, ... (SG)
Networking Aspects Network Layer &
Protocol Stack,
(Network “Waveforms”)State
Machines
Physical Layer &
Radio Aspects
Data
Layer
(Basic “Waveforms”) StateLink
Machines
HAVE
QUICK
Front End Network Protocol
Processing Security Stack
Modem
INFOSECData Processing
Voice
Infrastructure State Machines Domain/Resource Manager
Infrastructure Aspects
Real-time CORBA/IDL
Real-Time Distributed Processing Services
OS’s
Antennas, RF (Band, Bandwidth)
FPGAs
GP Hosts
Hardware Platform
Operating System (UNIX,…)
ASICs
DSPs
Instruction Set Architecture
40
© ICU 전파교육연구센터 2003
SDR Layers
Waveform/Applications
Framework
Application
Services Frameworks
Management Framework
Computational Framework
Platform
Services
Platform
41
Middleware (ORB)
OS Interface Standard(POSIX)
Operating System
Hardware Abstraction Layer
© ICU 전파교육연구센터 2003
Hardware
SDR Architecture
External environment
Source
set
Channel set
Evolution
support
Source coding
Service and
INFOSEC
and decoding Network support
Modem
Joint control
Multiple personalities
42
© ICU 전파교육연구센터 2003
IF
RF/channel
processing access
Channel coding and
decoding
Software Radio Layering Model
Data
Link
bytes
Link
Framing
bits
Channel
Encoding
bits
Line
Encoding
symbol
bytes
Link
Data
Framing
Link
bits
Channel
Decoding
bits
Line
Decoding
symbol
Modulation
Demodulation
discrete signal
Multiple
Access
Physical
discrete signal
D/A
Converter
continuous signal
RF
Transmitter
continuous signal
43
discrete signal
Multiple
Access
software
discrete signal
A/D
hardware
Converter
continuous signal
RF
Receiver
wireless medium
© ICU 전파교육연구센터 2003
Physical
continuous signal
Standardization
44
Application
Application
Application
APIs
APIs
APIs
APIs
Bindings
Bindings
Bindings
Bindings
RTOS
RTOS
RTOS
RTOS
BSP
BSP
BSP
BSP
HW
HW
HW
HW
© ICU 전파교육연구센터 2003
Standardized
Application
“Smart-Radio-on-a-Chip”
IP-based
network
기술
주파수
직접
변환기술
Monodyne
변복조 및
부호화 기술
45
© ICU 전파교육연구센터 2003
Design Issues of SDR Modem
DSP
• Using signal processing
compensate a microwave
circuit deterioration
• Recognize what kind of
signal processing is done
in RF-Band and Baseband
46
SDR
MICROWAVE
© ICU 전파교육연구센터 2003
CIRCUIT
ADC/DAC
4G Modem Technologies
–
–
–
–
Reliable High Rate/Broadband Transmission
Flexible applying of various modulation
Adaptive SDR System to Varying Channel & QoS
More Capacity & Spatial Diversity =>
Space-Time Processing
– Multiple Access for Higher rate packet
– High Spectral Efficiency => OFDM
– For Varying Channel & QoS => Link Adaptation
Techniques
47
© ICU 전파교육연구센터 2003
Signal processing in base-band
and IF/RF
base-band
Echo cancellation
Equalization
spectrum spreading
de-spreading
Synchronization
스마트안테나
전자파 간섭 및 잡음 제거
SDR의 대상서비스를 모두 수용하는 RF 회로 제작
필요 (GSM2Plus + CDMA + 3GPP + 3GPP2 시스템)
멀티모드 RF front-end의 주파수-밴드 선택/스위칭
다른 스펙트럼 신호가 동일 시간에 상호간 간섭이
없는 RF
modulation/
Demodulation
저전력, 광대역 PDC/PUC (Programmable Down/Up
Converter)
Timing recovery
고효율/선형 RF 전력증폭기
coding/decoding
다중 모드 동작 주파수 직접 변환
주파수 직접변환 회로 없이 RF신호를 직접 디지털화
여러 주파수 신호의 변환을 위한 PLL 모듈에서의
VCO 출력 설정
CDMA,OFDM 혼용
48
IF/ RF
© ICU 전파교육연구센터 2003
Digital Radio
Selects the channel according to different carrier frequency
and different channel bandwidth using fixed analog-defined
channel selection filters.
Downconvert
(LNA/Mixer
/Filter)
Diplexer
Diplexer
Frequency
Synthesizer
Digital
Output
IF
Processing
(Amp)
Upconvert
(Mixer/
Filter
/Amp)
Baseband
Processing
(Modem)
Bit-stream
Processing
Analog
Output
RF
Processing
Analog
49
© ICU 전파교육연구센터 2003
Digital
Software Defined Radio
(Heterodyne 구조)
the multi-channels are fed to the single wideband analog-stage.
Then all channels are converted to digital signal with one
wideband high-speed ADC. The desired channel is then selected
from the digitized multi-channels with the software-defined
channel selection filters in the digital-stage.
Diplexer
Amp
A/D
D/A
IF
IF
Processing
(Channelizer
/De- /Dechannelizer)
Analog
50
Baseband
Processing
Processing
(Modem)
(Modem)
Digital
© ICU 전파교육연구센터 2003
Bit-stream
Processing
Software Radio
(Homodyne 구조)
Software
Hardware/Software Co-design
DAC
DAC
Reconfigurable
(Programmable)
Processor
- Processor
ADC
ADC
51
© ICU 전파교육연구센터 2003
Network
Network
하드웨어 기반에서 소프트웨어 기
반으로의 변천
52
© ICU 전파교육연구센터 2003
A “mostly digital” receiver
architecture
RF
Filter
Custom Analog IC
Analog
Front-End
53
A/D
Converter
Custom Digital IC
Digital
Baseband
Processing
• “Go digital” at the earliest possible stage
• Use system level design choices to
simplify the analog RF requirements as
much as possible
• Rely on low power digital design
techniques to compensate for increased
baseband complexity
© ICU 전파교육연구센터 2003
Step 1: make as much of the circuitry
digital as possible
P r o g r a m m a bl e D S P
I
Q
I-F
DIGITAL
I-F
UPCONVERTER
RF
UP
CONVERTER
Wideband
DAC
I
I-F
DIGITAL
Wideband
I-F
ADC
Q DOWNCONVERTER
AGC
RF
DOWN
CONVERTER
Information
output
Software-Defined Cellphone
54
© ICU 전파교육연구센터 2003
RF
POWER
AMP
RF
LOWNOISE
AMP
ANTENNA SWITCHING SYSTEM
Information
Input
Ant
Step 2: achieve programmability at higher
frequencies to reduce hardwares to be used
for multi-mode cellphone
Information
Input
Programmable DSP
I
Q
I
Q
Wideband
DAC
RF
Quadrature
upconverter
Wideband
DAC
Wideband
ADC
Wideband
ADC
Quadrature
downconverter
Information
output
Direct-Conversion Cellphone
55
AMP
RF
AGC
AGC
POWER
© ICU 전파교육연구센터 2003
LOWNOISE
AMP
Ant
Dual Mode (2G/3G)
Transceiver Configuration
DSP
FRONT
END
WB
FIL
P.A.
WB
FIL
SPREAD
FRONT
END
NB
FIL
DEM
P.A.
NB
FIL
MOD
A/D
DE
SPREAD
RAKE
DEM
for 3G System
MOD
CODEC
ANT
CONT
for 2G System
CONT
56
© ICU 전파교육연구센터 2003
CODEC
W-CDMA,CDMA2000 통합시스템
Algorithm
RF
Conversion
to IF
and A/D
Modulator
Demodulator
Despreader
Searcher
Time Tracker
AFC
Channel estimator
Lock detector
RAKE combiner
Power control
Channel codec
Rate matching
Multiplexing
Partitioning
CDMA2000
S/W part(DSP)
WCDMA
S/W part(DSP)
H/W part
(ASIC)
Flexible H/W part
(FRBA or FPGA)
Baseband processing
I/O controller
57
Process controller
© ICU 전파교육연구센터 2003
Program memory
16
Problems in SDR
• Existing portable phones are very
compact, with long battery life, High
MIPS and low cost.
• Illegal use causes serious interference
• Download problem.
– The volume of s/w downloaded
increases -> time is lengthened
– Manufacturer-specific know-how can
be leak out – security
– S/W Virus or hackers
• The method of managing several units
for multi-mode and multi-mode systems
and placement of broadband antenna
58
© ICU 전파교육연구센터 2003
More Performance for future
SDR
• High frequency
– MMIC(Monolithic Microwave Integrated
Circuit) – analog
• Interface between analog and digital
– wideband/high speed/high resolution ADC
and DAC chip
• Digital Processing
- DSP (Digital Signal Processor)
– ASIC (Application Specific Integrated Ci
rcuit)
– FPGA (Field Programmable Gate Array)
59
© ICU 전파교육연구센터 2003
Some Quotes from SDR Forum
“SDR delivers a robust set of features to the consumer in a cost efficient
manner for the provider.” - Brian Tropper, President, Tropper
Technologies
“SDR bridges multiple standards as well as legacy and future systems.” Dr. Eric Christensen, Technical Staff Engineer, Motorola
“SDR has great a future and will open the doors for software developers.”
- Mark Adams, VP, Software Technology, Inc
“Time is now. Vendors have technology in place to offer products.” Mark Cummings, President, CEO, enVia
“Its inevitable.” - Graham Mostyn, VP System Engineering, Chameleon
Systems
“SDR is a mainstream way to solve problems.” - Rodger Hosking, VP,
Pentek
“Harris is a strong supporter of SDR.” - John Fitton, Senior Scientist,
Harris Corp.
“SDR is indispensable.” - Mitsuyuki Goami, General Manager, Kokusai
Electric Co
“SDR will be the only way radios operate.” - Karl Davis, Senior Principal
Software Engineer, Raytheon
60
© ICU 전파교육연구센터 2003
Software Radio Phase Space
61
© ICU 전파교육연구센터 2003
SDR Adoption Timeline,
SDR Forum
Duration
2000
Base Stations
Product Introduction
2001
2003
Limited use by
Infrastructure
Manufacturers
2005
Increased use due to 3G
62
Terminals
Almost no usage
Initial usage as multi-mode, multiband Cellular/PCS in high-end
and roaming products
Used for 3G capabilities
(“information centric” product,
embedded applications in computers,
autos...)
Widespread adoption by most
manufacturers as core
platform
© ICU 전파교육연구센터 2003
Reconfigurable Radio Systems
Business Model
Applications
Base Stations
Network
“Application”
“System”
Terminals
Middleware
Services
Enabling Technologies
63
© ICU 전파교육연구센터 2003
Regulation
Spectrum
Standards
R&D in Reconfigurable Radio Systems &
Networks in Europe
(number of projects)
5
4
3
2
64
Spectrum
Antenna
RF
IF
Baseband
0
Application
1
© ICU 전파교육연구센터 2003
Terminal
Base Station
Network
Business Model
Project
Asian Activities
Players
Focus
3GPP WCDMA
SDR Test Bed
Samsung (WCDMA+CDMA2000)
상용화
(GSM+WCDMA) 진행중
Receiver technology, global
roaming, multi-mode operation
Software Radio
Base & Personal
Station
Prototypes
NTT
Adaptive array
antennas,modulation,signal
processing, over-the-air
downloads
ARIB - Software
Receiver
Technology
ARIB (Toshiba, Anritsu, Gunma
Univ, Koden Electronics, KDD,
Shizuoka Univ, Tokyo Inst of
Tech, Tohoku Univ, NEC, JRC,
Fujitsu, Japan Defense Academy,
CRL)
Receiver technology,
reconfiguration, software
downloads
SDR Test Bed
SK Telecom
Reconfigurable equipment and
services - Planning Phase
Hardware
Platform of the
SW Radio
National Natural Science
Foundation of China & Tsinghua
Univ
Reconfiguration & Hardware
Architecture
65
© ICU 전파교육연구센터 2003
European Activities
Project
Players
LCM – Mobile Communications
Laboratory
Swiss Federal Institute of
Technology in Lausanne &
Institut Eurecom
TRUST (Transparently
Reconfigurable UbiquitouS
Terminal)
European Commission –
User terminal
(France Telecom, Telefonica, reconfiguration, multi-mode,
Siemens, Motorola,
multi-band operation
Panasonic, Bosch)
http://www.ist-trust.org
66
Focus
PASTORAL (Platform And
Software for Terminals:
Operationally ReconfigurAbLe)
SODERA (re-configurable low
power radio architecture for
SDR)
European Commission – (ST
Microelectronics, Alcatel,
France Telecom, CSELT,
Sirius, Thomson)
MOBIVAS (Mobile ValueAdded Services)
European Commission –
(Thomson, NEC, Unis,
Innovators, Hellenic
Telecommunications Org,
Ecole Nationale Superieure
des Telecommunications)
3G real time test bed;
adaptive antennas,
reconfiguration, multi-user
antennas, base stations
Re-configurable, real-time
platform for 3G mobile base
band development
http://www.ist-sodera.org
© ICU 전파교육연구센터 2003
Define, design, develop, and
validate an integrated
application architecture for
SDR software downloads
North American Activities
67
Project
Focus
CHARIOT (Changeable Advanced Radio
for Inter-Operable Telecommunications),
Government &Virginia Tech
Smart antenna and reconfiguration
JTRS(Joint Tech. Radio System)
객체지향 sw 구조, SDR forum의 상
업적 모델을 위한 규격
2001.11 SCA 2.2
ISI(Information Sciences Institute)
CPU, GPS 수신기, 무선 인터페이스가
혼합 사용될 수 있도록 통합
SORT (Software radio technologies)
SLATS (Software libraries for advanced
terminal solutions)
PROMULA (Programmable Multimode
radio for multimedia wireless terminals)
Standardization
© ICU 전파교육연구센터 2003
SDR 등장배경 -군용
• 육해공군 및 국제연합작전 시 통신 어려
움
• 무선 군용 고속 네트워크망을 위한 단말
기 필요성 대두
 C4I에 의한 국방정보화 사업 가속화
• 통신장비의 빈번한 교체에 따른 경제적
부담
68
© ICU 전파교육연구센터 2003
• SDR 표준화(상용,군용) 단체,
 1996년 창설, 미국 주도
 분산 객체 구조, S/W 다운로드, 보안과 암호
화를 위한 표준화 작업
 모든 프로토콜들에 대한 정책적 경제적 규정
에 대한 방책까지 연구
69
© ICU 전파교육연구센터 2003
SPEAKEasy
• 1970년대부터 국방성 산하 연구소인 DARPA의 주도로
다양한 대역을 사용하는 상이한 군용 통신 규격간의 통
합 송수신 시스템 개발
• 개방형 구조를 채택한 모듈 단위의 재구성이 가능
• 새로운 무선 방식을 용이하게 추가할 수 있는 포괄적인
소프트웨어 구조의 개발
• Phase-1단계 (1992년 - 1995년): 고속 주파수 도약
대역 확산 파형에 대하여 4-채널, 광대역 모뎀을 개발하
여 타당성을 확인
• Phase-2단계 (1995년부터 2000년): 사용자의 입력-출
력단부터 RF 단에 이르는 전체 라디오 시스템에 대한 개
방형, 모듈 단위, 재프로그램이 가능한 구조의 상업용
모듈과 표준
70
© ICU 전파교육연구센터 2003
Joint Tactical Radio System
AN/PRC-117F SDR 무전기, Harris
Joint Tactical Radio System 2C
지대지, 지대공, 지대위성간 비화 통신을 제공
현재 미국의 모든 군에서 사용중인 다중
대역/다중 임무 무전기
30-512 MHz 대역
71
동시 다중 채널의 음성, 데이터, 화상 및 비디오
지상, 함정 탑재 및 항공기 탑재 플랫폼
스펙트럼 확산 변조(저피탐 및 항 재밍)의 사용
송신 출력 제어 및 내장 암호화로 보안성과
225∼400 MHz의 주파수 범위
© ICU 전파교육연구센터 2003
GloMo Project
(Global Mobile Information)
 BBN Technologies
- Support for distributed real-time
MMWN(Multimedia applications in Mobile Wireless
Networks)
 SRI International
- Advanced secure wireless integrated networks
 Camegie Mellon University
- Pyxis-Middleware for distributed multimedia
programming
 Rutgers University
- Dataman project-information services for low
powered mobile clients
- Numble-many time, many where communications
support for information system
72
© ICU 전파교육연구센터 2003
GloMo Project
 SAIC
- SEAM-LSS(Simulation and Evaluation of Adaptive
Mobile Large Scale networks Systems)
 Virginia Tech MPRG(Mobile and Portable Radio
Research Group)[8]
- Software radio using reconfigurable computing
 Stanford University
- Low power distributed mobile networks
- Reconfigurable multimode, multi-band information
transfer systems
 UTPA(University of Texas-Pan American)
- 높은 데이터율의 재구성 가능한 안테나 개발
- Generic control channel mechanism
73
© ICU 전파교육연구센터 2003
GloMo Project
 UCLA(University of California in LA)
- Handheld untethered nodes for high performance
wireless network systems
- Design of mobile adaptive networks using simulation
and agent technology(GloMo SIM)
 UCSC(University of California, Santa Cruz)
- SPARROW(Secure Protocols for Adaptive, Robust,
Reliable, and Opportunistic WINGs)
 University of California, Berkeley[10]
- Towards a wireless overlay internetworking
architecture
- BARWAN(Bay Area Research Wireless Access
Network)
 University of Kansas
- RDRN(Rapidly deployable radio networks)[11]
74
© ICU 전파교육연구센터 2003
CHARIOT, Virginia Tech
(Changeable Advanced Radio for Inter Operable Telecommunications)
 적응 배열 구조 연구
- 협대역 적응안테나 테스트베드 개발
 간섭에 강한 단말기 수신기에 대한 연구
- Analog Device사의 ADSP-21020을 이용하여 적응 알고리즘 실행 및 기
저대역에서 테스트
 간섭에 강한 기지국 수신기에 대한 연구
- Analog Device사의 ADSP-21020을 이용하여 multistage 수신기 동작
및 기저대역에서 테스트
 재구성 가능한 컴퓨팅 구조에 대한 연구
 구조 특성과 디자인
- 소프트웨어 라디오와 컴퓨팅 구조 정의 모델
- 상위 레벨 라디오 디자인
 소프트웨어 라디오 알고리즘 모델링과 동작
- 터보 코드 알고리즘 개발
 핸드헬드 스마트 안테나
75
© ICU 전파교육연구센터 2003
AFFL/IF
Multiband Multimode Radio
•
•
•
•
•
•
•
•
76
기존 무선 네트웍과 상호 동작
광대역 전력 증폭기 및 광대역 안테나
Radio 동작과 리소스의 SW 제어
이동성증대를 위한 파형 표준화
서비스 요구와 환경 변화 인지 적응
정보 보호 서비스 및 QoS
무선시스템과 안테나 플랫폼 통합
JTRS compliant plug and play HW/SW 응용
모듈 개발
© ICU 전파교육연구센터 2003
Commercial SDR Drivers
• Global Cellular/PCS Markets
• US - delayed to exploit capital investment in analog systems
• Europe - GSM to share common R&D & platforms
• Japan - Exhausted PHS & PDC spectrum for CDMA
• Proliferation of standards and spectral capacity
call for multiband, multimode services on single carrier systems
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Market
First Generation
USA
AMPS & Derivatives TDMA, CDMA, GSM UW136, Edge/NA,
3GCDMA-DS, 3GCDMA-MC
Japan
NTT-Analog, JTACS PHS, PDC, GSM
3GCDMA-DS
Europe
Various Analog Stds GSM
IMT-2000, 3GCDMA-TDD
Second Generation
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Third Generation
Business Model for Wireless PCS
Financial Institution
Peter G. Cook, Stephen Hope
APn
FI
Application
Providers
Regulators
OEMn
OEM System
Suppliers
MMM
MultiMedia
Mgr
NO
SP
Service Provider
“Clearcut
Communications”
Network
Operator
CPn
FD
Function
Developer
(SDR)
Transaction Flow
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© ICU 전파교육연구센터 2003
Users
Enhanced
Capability
WL
Content
Providers
Um
Wireline
Operator
PAN
Wireless
Personal Area
Network
RN
Roaming
Network
Operating
Generic Business Model
HW
Upgrade
Specify
Define System
Consultant
Customer
Asynchronous lifecycles
Product 8 years
Chips 3 years
Sw / Com. 2 years
Various Military Programs
SW 3d party
Editor
System
Responsible for multiple WFs
Provider
Interconnect with
net provided by
Responsible for 1 WF
Integration
validation
certification
Integrator
WF Assembler
GLUE
HW
Manufacturer
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Editor
Fee : OS, ORB, SCA ...
SW
Editor
© ICU 전파교육연구센터 2003
GNU Radio
Eric Blossom, eb@comsec.com
• It’s a free software defined radio
• A platform for signal processing on
commodity hardware
• Create a practical environment for
experimentation & product delivery
• Expand the “free software ethic” into
what were previously hardware intensive
arenas
• http://www.gnu.org/software/gnuradio
• http://www.opencores.org/projects/pci
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© ICU 전파교육연구센터 2003
Conclusion
• SDR is useful
cost saving (not necessary replacing
hardware)
enhancing the system performance of
functions
• SDR depends on
- progress of hardware technology and
- high speed and low power consumption
DSP and ADC/DAC, tunable and low loss
filter, ultra wideband power amplifier
• Standardization of SDR
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© ICU 전파교육연구센터 2003
참고 문헌
• Software Radio Architecture ObjectOriented Approaches to wireless
Systems Engineering - J. Mitola III
• Simulation and Software Radio for
mobile communications - H. Harada & R.
Prasad
• Software Defined Radio, Origins,
Drivers and International Perspectives
edited by Walter Tuttlebee
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