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Home , 3G, CDMA2000, CdmaOne

MOBILE Radiocommunication testers

Universal Radio Communication Tester R&S CMU200 CDMA2000 – a new challenge for mobile radio testers

The CDMA world is facing its next The CDMA2000 market 120 100 decisive step: the introduction of Since the launch of the first commercial 80 cdmaOne network in Hong Kong in 60 CDMA2000 1X, handling packet data September 1995, CDMA has established 40 itself worldwide as a mobile radio

Subscribers (millions) 20 rates of up to 307.2 kbit/s. The standard. It has advanced triumphantly 0 far beyond the USA, its country of origin, Jun. 98 Jun. 99 Jun. 00 Jun. 01 future-oriented measurement platform Korea and . With rocketing growth Dec. 97 Dec. 98 Dec. 99 Dec. 00 Dec. 01 rates, CDMA ranks besides GSM as a Universal Radio Communication Tester major digital standard of the second FIG 1 Development of cdmaOne/CDMA2000 subscriber figures generation. Now the CDMA world is R&S CMU200 also supports this third- entering a new and decisive phase, the introduction of CDMA2000 1X, which is generation mobile radio standard. capable of working with packet data rates of up to 307.2 kbit/s. in Korea and Japan is almost saturated, the highest growth rates have lately In recent years, cdmaOne has expanded come from North and South America, tremendously fast. In April 1998, there and a large market is emerging in were around ten million subscribers . The network operator China worldwide, but now more than Unicom is presently setting up a 100 million customers make their calls cdmaOne/CDMA2000 network, with through CDMA networks (FIG 1). This capacity expected to serve some 50 development is remarkable in as much million subscribers by the year 2005. as GSM had already established itself worldwide as the de facto standard. CDMA2000 is the logical successor to Photo 43238/16 cdmaOne. Since cdmaOne is a subset paved the way for this enormous of the IS 2000 standard, operators can growth, headed by , which easily upgrade their networks without placed all its bets on cdmaOne. Japan losing functionality. CDMA2000 base also became an important CDMA bas- stations are capable of communicating tion. KDDI, the only cdmaOne network with cdmaOne phones and CDMA2000 operator in Japan, can boast more phones can do the same with a than ten million subscribers and a cdmaOne base station. It is understand- market share of about 20%, making able that almost all cdmaOne network it serious competition for the market operators plan to offer additional ser- leader NTT DoCoMo. While the market vices based on CDMA2000.

Further articles on the R&S CMU200 can be found on pages 9 and 12 of this edition.

4 News from Rohde&Schwarz Number 173 (2002/I) As was the case with cdmaOne, Korea Characteristics of forward link CDMA2000 overview again led the way and SKTelecom was the first to put a CDMA2000 network The individual physical channels are CDMA2000 is a follow-on development into operation in October 2000. Most distinguished by means of orthogonal of the established TIA/EIA 95 A/B cdmaOne network operators plan to put Walsh codes (FIG 3). Codes of different standard for second-generation mobile their CDMA2000 networks on the air length are used to obtain different data radio. The extensive backward com- by the beginning of 2002 (FIG 2). First rates from a constant rate for the patibility of signalling and network networks are also planned in Eastern actual information bits. Convolutional characteristics considerably simplifies Europe (Romania, Moscow, Saint Peters- coders are used for conventional voice introduction. For instance, CDMA2000 burg) in the 450 MHz band, which and data services, and turbo coders for islands can be implemented in the became vacant a short time ago. the high data rates of the supplemental overlay of an existing cdmaOne net- channels. work during a transition period. Basi- Producers of CDMA mobile radio equip- cally, two introductory phases are dis- ment need a platform that offers high If the number of Walsh codes is no tinguished for CDMA2000. accuracy and speed as well as multi- longer sufficient because the orthogonal mode capabilities. Just in time for the vector space is exhausted, channel sepa- In the first step, CDMA2000 1X introduction of CDMA2000 in North ration can be continued with the aid of (1xRTT*) is implemented with a signal America, the future-oriented measure- non-orthogonal functions. Quasi-orthogo- of 1.25 MHz and a spread- ment platform R&S CMU200 is now nal functions (QOFs) are created by mask- ing rate (SR) of 1 (i.e. 1.2288 Mchip/s). also able to support this third-generation ing existing Walsh codes. The frame This corresponds to the physical char- mobile radio standard. lengths for signalling and user informa- acteristics of cdmaOne. CDMA2000 1X offers more code channels (128 Walsh codes) on the forward link, the con- nection from the base station to the . In addition, fast FIG 2 Most CDMA2000 networks will go into operation by early 2002. power control is introduced also on the forward link. Packet data Country Operator Test / start rates of up to 307.2 kbit/s for sta- rd Test 3 quarter/2000 tionary and mobile applications can th Brazil Global Telecom Start 4 quarter/2001 be handled; voice quality and capacity th Brazil Telesp Celular Start 4 quarter/2001 are almost doubled. CDMA2000 1X Brazil Vesper Start 4th quarter/2001 supports new antenna techniques Start 4th quarter/2001 such as spot beams for covering lim- Canada Test 3rd quarter/2000 ited areas with high traffic volume for Chile SmartCom PCS Start 1st half/2002 short periods. Japan KDDI Start 1st half/2002 Korea KT Freetel In operation In the subsequent phase, CDMA2000 Korea LG Telecom In operation 3X (3xRTT) with an SR of 3 Korea SK Telecom In operation (3.6864 Mchip/s) offers three times Mexico Pegaso PCS Start 4th quarter/2001 the bandwidth of cdmaOne. Peak New Zealand Telecom Mobile Limited Start 4th quarter/2001 data rates of up to 2 Mbit/s allow Ukraine CST Invest Limited Start 1st quarter/2002 true multimedia applications. A precise time schedule for the introduction USA AirGate PCS Start 1st quarter/2002 of 3X is not yet available. Presently, USA Alamosa PCS Start 1st quarter/2002 the CDMA2000 1xEV-DO system is USA Communications Start 2nd half/2001 being promoted – a CDMA method USA Horizon PCS Start 3rd quarter/2002 developed by and optimized USA Sprint PCS Start 4th quarter/2001 for data transmission. USA Start 2nd half/2001 Venezuela Test 1st half/2001 Vietnam Saigon Postel Start 2nd half/2001 * RTT: radio transmission technology

5 News from Rohde&Schwarz Number 173 (2002/I) MOBILE RADIO Radiocommunication testers

tion vary between 5ms, 20ms, 40ms station. Traffic data is transmitted in an ◆ RC1 and RC2 define cdmaOne and 80 ms. Another specified possibility independent fundamental channel (FCH) connections for rate sets 1 and 2 is that under certain conditions system and in supplemental channels (SCHs) ◆ RC3 to RC5 on the forward link (RC3 capacity can be increased by splitting up with separate power and targets for and RC4 on the reverse link) define the forward link signal to several trans- frame error rate (FER). CDMA2000 connections for spreading mit antennas (transmit diversity). rate 1 (CDMA2000 1X) As on the forward link, convolutional ◆ RC6 to RC9 on the forward link (RC5 coders are used for low-rate voice and and RC6 on the reverse link) are Characteristics of reverse link data transmissions and turbo coders reserved for CDMA2000 connections for the new, high data rates of the for spreading rate 3 (CDMA2000 3X) In contrast to cdmaOne, the channels of supplemental channels. A new feature a true CDMA2000 link are distinguished is fast control of base station power by Service options define possible connec- by different Walsh codes and split up in the mobile station (forward link power tion modes and their parameters, e.g. the complex baseband into the inphase control). the different speech modes (depending (I) and the quadrature (Q) path. Different on the voice coder used), SMS, and channels can be used depending on Nine different radio configurations (RCs) other data links, or especially test loop- the (QoS) and physical on the forward link and six on the backs. channel characteristics (FIG 4). On reverse link determine the different the reverse link, a continuous pilot connection modes defined by the CDMA2000 operates worldwide in dif- simplifies synchronization to the base IS2000 standard: ferent frequency bands. Presently, the standard defines eleven different band classes, all of which are of course cov- ered by the R&S CMU200.

FIG 3 New physical channels on the forward link of CDMA2000

New forward link common channels for CDMA2000 mobile phones CDMA2000 in R&S CMU200 Pilot channels (PICH) Permit transmit diversity (F-TDPICH, F-ATDPICH); support Implementation of the CDMA2000 1X applications (F-APICH) standard in the R&S CMU200 is based Quick paging channel (QPCH) Improved slotted mode, longer battery lifetime; 128 128 128 on the TIA/EIA specification IS 2000 Walsh codes W80 , W48 , W112 , reserved for F-QPCH Rev.0. Like in all mobile radio networks Common control channel (CCCH) F-CCCH transmits mobile directed supported by the R&S CMU200, there is for CDMA2000 mobile phones a distinction between signalling and non- Broadcast channel (BCCH) F-BCCH transmits broadcast and signalling mode. All major network, base overhead messages (e.g. SMS) station and link parameters are clearly Common power control channel Used together with enhanced organized and configurable (FIG 5). The (CPCCH), common assignment access channel procedures implementation of CDMA2000 in the channel (CACH) R&S CMU200 particularly takes into account all innovations of the IS 2000 New forward link dedicated channels for CDMA2000 mobile phones standard. Forward fundamental Transmits signalling/user information for a channel (F-FCH) specific ; each For instance, the R&S CMU200 also sup- traffic channel may contain an F-FCH ports the quick paging channel (QPCH) Forward dedicated Transmits signalling information for a used to extend battery lifetime. In addi- control channel (F-DCCH) specific mobile phone; each tion to the normal configuration, it is traffic channel may contain an F-DCCH possible to define in the test system Forward supplemental Transmits user information for a specific channel (F-SCH) mobile phone; used for high data rates; whether or not the QPCH addresses the each traffic channel may contain DUT. This ensures that the mobile phone two F-SCHs observes the QPCH and not the normal pilot channel or the common control Power control subchannel Used together with F-FCH or F-DCCH channel F-CCCH.

6 News from Rohde&Schwarz Number 173 (2002/I) CDMA2000 measurements The R&S CMU200 supports common Reverse CDMA Channel for Spreading Rates 1 and 3 (SR1 and SR3) cdmaOne measurements such as standby/access probe power, sideband suppression, gated output power, open- Reverse Reverse Reverse Enhanced Common Traffic loop time response, min./max. output Access Traffic Access Control Channel power and receiver quality (frame Channel Channel Channel Channel Operation (RC 1 or 2) Operation error rate). In contrast to cdmaOne, a Operation (RC 3 to 6) CDMA2000 mobile phone sends on dif- ferent code channels, possibly with dif- ferent data rates and levels. A signal Reverse Reverse Reverse Reverse Fundamental Pilot Pilot Pilot of this complexity typically has a higher Channel Channel Channel Channel peak/average power ratio than a signal 0 to 7 Reverse 0 or 1 Reverse Enhanced Access Reverse Common with only one channel as in cdmaOne. Supplemental Dedicated Control Channel Control Channel This calls for power amplifiers with a Code Channel Channel wider dynamic range. CDMA2000 allevi- 0 or 1 Reverse ates this problem through the use of Fundamental Channel QPSK with a peak-limited 0 or 2 Reverse spreading function. The result is the Supplemental hybrid phase shift keying (HPSK) modula- Channels tion mode (FIG 6). Consequently, com- Reverse Power Control pletely new modulation measurements FIG 4 Depending on the operating mode, different physical channels are used on the Subchannel and – new on the CDMA reverse link – reverse link of the new 3G standard CDMA2000. a code domain power measurement are required (FIG 7).

FIG 5 All relevant base station, network and link parameters are clearly FIG 6 Constellation diagram of a CDMA2000 reverse link signal with organized on the R&S CMU200. F-PICH, F-FCH and one active F-SCH.

7 News from Rohde&Schwarz Number 173 (2002/I) MOBILE RADIO Radiocommunication testers

Another innovation, forward power R&S CMU200 rises to the control, enables the mobile station to occasion More information and data sheet at www.rohde-schwarz.com control the output power of the base (search term: CMU200) station in the dedicated channels. The In terms of CDMA2000, the hardware R&S CMU200 performs a comprehensive and concept of the R&S function check of this new CDMA2000 CMU200 has again proven its great feature (FIG 8). flexibility. The test system is now all set to go for measurements on future

AMPS measurements CDMA generations such as CDMA2000 Universal Radio Communication Tester CMU200 THE tester for current and future mobile radio networks

• Multi-protocol support • Extremely high speed testing • Highly accurate measurements Especially in North America, mostly dual- 1xEV-DO, etc. • Modular future-proof design • Comprehensive spectrum analyzer • Easy migration to 3rd generation technologies mode CDMA mobile phones using AMPS Michael Altmann; Thomas Rösner (advanced mobile phone system) are sold. For this reason, the R&S CMU200 also supports this analog standard of the Data sheet R&S CMU200 first network generation. Its AMPS func- REFERENCES tionality boasts innovative concepts such The Universal Radio Communication Tester as multitone measurement to check AF R&S CMU200 has continually been upgraded frequency response in the transmitter to keep pace with technical developments. There have been reports on the measurement and receiver of the mobile phone. capabilities and innovations of this state-of- the-art communication tester in almost every edition of this journal since the instrument was first introduced in News from Rohde & Schwarz No. 165 (1999). See REFERENCES on page 14.

FIG 7 The code domain power measurement verifies the correct level of FIG 8 Forward power control measurement. the physical channels on the reverse link.

8 News from Rohde&Schwarz Number 173 (2002/I)