0-Ora000003 Cdma2000 Principle Issue4.0

March 17, 2018 | Author: udaasnaslain | Category: Forward Error Correction, Modulation, 3 G, Networks, Mobile Technology


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ORA000003 CDMA2000 PrincipleISSUE4.0 HUAWEI, Mobile Network Curriculum Development Section Objectives After this presentation, you will be familiar with:  the development of mobile communication system  the structure of CDMA2000 network  the number planning in CDMA2000 network  the techniques used by CDMA system including: source coding, channel coding, interleaving, scrambling, spreading and modulation etc. power control, soft handoff, RAKE receiver F-PCH,F-PICH,F-SYNCH,F-FCH,F-SCH,R-ACH,R-PICH  Long code, short code and Walsh code Course Organization Chapter 1: Introduction Chapter 2: CDMA Techniques & Technologies Chapter 3: CDMA Air Interface Chapter 4: CDMA Core Networks Chapter 5: CDMA Number Planning 1 st Generation 1980s (analog) 2 nd Generation 1990s (digital) 3 rd Generation current (digital) 3G provides:  Complete integrated service solutions  High bandwidth  Unified air interface  Best spectral efficiency and ……………… a step towards PCS AMPS Analog to Digital TACS NMT OTHERS GSM CDMA IS95 TDMA IS-136 PDC UMTS WCDMA CDMA 2000 TD- SCDMA Development of Mobile Communications Introduction Voice to Broadband Transmission Techniques Traffic channels: different users are assigned unique code and transmitted over the same frequency band, for example, WCDMA and CDMA2000 Traffic channels: different frequency bands are allocated to different users,for example, AMPS and TACS Traffic channels: different time slots are allocated to different users, for example, DAMPS and GSM Power Power Power FDMA TDMA CDMA Introduction TDMA Power Introduction 3G Objectives 3G is developed to achieve:  Universal frequency band for standard and seamless global coverage  High spectral efficiency  High quality of service with complete security and reliability  Easy and smoothly transition from 2G to 3G, compatible with 2G  Provide multimedia services, with the rates:  Vehicle environment: 144kbps  Walking environment: 384kbps  Indoor environment: 2Mbps Introduction Standards for 3G 3G system CDMA2000 3GPP2 FDD mode WCDMA 3GPP FDD mode TD-SCDMA CWTS TDD mode Introduction A Comparison b/w 3G standards WCDMA CDMA2000 TD-SCDMA Receiver type RAKE RAKE RAKE Close loop power control Supported Supported Supported Handoff Soft/hard handoff Demodulation mode Coherent Chip rate (Mcps) 3.84 N*1.2288 1.28 Transmission diversity mode TSTD, STTD FBTD OTD, STS No Synchronization mode Asynchronous Synchronous Asynchronous Core network GSM MAP ANSI-41 GSM MAP Coherent Coherent Soft/hard handoff Soft/hard handoff Introduction IS95A 9.6kbps IS95A 115.2kbps CDMA2000 307.2kbps  Heavier voice service capacity ;  Longer period of standby time CDMA2000 3X CDMA2000 1X EV 1X EV-DO 1X EV-DV 1995 1998 2000 2003 Development of CDMA  Higher spectrum efficiency and network capacity  Higher packet data rate and more diversified services  Smooth transit to 3G Introduction Frequency Allocation In CDMA2000  Band Class 0 and Spreading Rate 1 Introduction Transmit Frequency Band (MHz) Block Designator CDMA Channel Validity CDMA Channel Number Mobile Station Base Station A(10MHz) Valid 1-311 825.030-834.330 870.030-879.330 B(10MHz) Valid 356-644 835.680-844.320 880.680-889.320 A’(1.5MHz) Valid 689-694 845.670-845.820 890.670-890.820 B’(2.5MHz) Valid 739-777 847.170-848.310 892.170-893.310 The transmit frequence point for Base Station is computed by: F=870+N*0.03 N: CDMA Channel Number Frequency Allocation In CDMA2000  Band Class 1 and Spreading Rate 1 Introduction Transmit Frequency Band (MHz) Block Designator CDMA Channel Validity CDMA Channel Number Mobile Station Base Station A(15MHz) Valid 25-275 1851.250-1863.750 1931.250-1943.750 D(5MHz) Valid 325-375 1866.250-1868.750 1946.250-1948.750 B(15MHz) Valid 425-675 1871.250-1883.750 1951.250-1963.750 E(5MHz) Valid 725-775 1886.250-1888.750 1966.250-1968.750 F(5MHz) Valid 825-875 1891.250-1893.750 1971.250-1973.750 C(15MHz) Valid 925-1175 1896.250-1908.750 1976.250-1988.750 The transmit frequency point for Base Station is computed by: F=1930+N*0.05 N: CDMA Channel Number CDMA2000 1X Network Structure MS: Mobile Station BTS: Base Transceiver Station BSC: Base Station Controller MSC: Mobile Switching Center HLR :Home Location Register VLR: Visitor Location Register PCF: Packet data Control Function PDSN: Packet Data Service Node HA: Home Agent FA: Foreign Agent SCP: Service Control Point Radius: Remote Authentication Dial-in User Service Abis A1(Signaling) A2(Traffic) A11(Signaling) A10(Traffic) A3(Signaling & Traffic) A7(Singaling) Introduction Course Contents Chapter 1 Introduction Chapter 2 CDMA Techniques & Technologies Chapter 3 CDMA Air Interface Chapter 4 CDMA Core Networks Chapter 5 CDMA Number Planning Correlation (a) (b) Correlation 100% so the functions are parallel Correlation 0% so the functions are orthogonal CDMA Techniques & Technologies +1 -1 +1 -1 +1 -1 +1 Orthogonal Function  Orthogonal functions have zero correlation. Two binary sequences are orthogonal if their “XOR” output contains equal number of 1’s and 0’s 0000 0101 0101 EXAMPLE: CDMA Techniques & Technologies 1010 0101 1111 Information spreading over orthogonal codes CDMA Techniques & Technologies 1 0 0 1 1 0110 0110 0110 0110 0110 1001 0110 0110 1001 1001 User Input Orthogonal Sequence Tx Data +1 -1 +1 -1 Information recovery CDMA Techniques & Technologies 1 0 0 1 1 +1 -1 Rx Data 1001 0110 0110 1001 1001 0110 0110 0110 0110 0110 1111 0000 0000 1111 1111 Correct Function ? ? ? ? ? Rx Data 1001 0110 0110 1001 1001 0101 0101 0101 0101 0101 1100 0011 0011 1100 1100 Incorrect Function Spreading and De-spreading information pulse interference White noise The improvement of time-domain information rate means that the bandwidth of spectrum-domain information is spread. S(f) is the energy density. f S(f) The spectrum before spreading information f0 The spectrum before despreading information Interference/noise S(f) f0 f f0 The spectrum after despreading information Interference/noise S(f) f The spectrum after spreading information f0 S(f) f CDMA Techniques & Technologies Signal flow Interleaving Source coding Convolution & Interleaving Scrambling Spreading Modulation RF transmission Source decoding deinterleaving Decovolution & Deinterleaving Unscrambling De-spreading Demodulation RF receiving CDMA Techniques & Technologies Common Technical Terms  Bit, Symbol, Chip:  A bit is the input data which contain information  A symbol is the output of the convolution, encoder, and the block interleaving  A chip is the output of spreading  Processing Gain:  Processing gain is the ratio of chip rate to the bit rate.  The processing gain in IS-95 system is 128, about 21dB.  Forward direction: Information path from base station to mobile station  Reverse direction: Information path from mobile station to base station CDMA Techniques & Technologies In a typical duplex call, the duty ratio is less than 35%. To achieve better capacity and low power consumption, base station reduces its transmission power. Source Coding Vocoder: 8K QCELP 13K QCELP EVRC Characteristics Support voice activity CDMA Techniques & Technologies Channel Coding Convolution code or TURBO code is used in channel encoding Constraint length=shift register number+1. Encoding efficiency= (total input bits / total output symbols) convolution encoder Input (bits) Output (symbols) CDMA Techniques & Technologies Turbo Code Turbo code is used during the transmission of large data packet.  Characteristics of the Turbo code:  The input information is encoded twice and the two output codes can exchange information with each other during decoding.  The symbol is protected not only by the neighborhood check bits, but also by the separate Check Bits. The performance of a Turbo code is superior to that of a convolution code. CDMA Techniques & Technologies Interleaving The direction of the data stream 1 2 8 7 3 6 4 5 1 2 8 7 3 6 4 5 1 2 8 7 3 6 4 5 1 2 8 7 3 6 4 5 1 2 8 7 3 6 4 5 1 2 8 7 3 6 4 5 1 2 8 7 3 6 4 5 1 2 8 7 3 6 4 5 1 2 8 7 3 6 4 5 1 2 8 7 3 6 4 5 1 1 1 1 1 1 1 1 2 2 2 2 2 7 7 7 7 7 7 7 7 6 6 6 6 6 6 6 6 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 1 2 8 7 3 6 4 5 1 2 8 7 3 6 4 5 5 5 5 5 5 5 5 5 8 8 8 8 8 8 8 8 i n t e r l e a v i n g CDMA Techniques & Technologies 2 2 2 Out 0 0 1 1 1 0 Scrambling (M) sequence  Two points are important here:  Maximum number of shift register (N)  Mask  The period of out put sequence is 2 N -1 bits  Only sequence offset is change when the mask is changed  PN stands for Pseudorandom Noise sequence CDMA Techniques & Technologies Long Code  The long code is a PN sequence with period of 2 42 -1chips  The functions of a long code:  Scramble the forward CDMA channel  Control the insertion of power control bit  Spread the information on the reverse CDMA channel to identify the mobile stations CDMA Techniques & Technologies PNa PNc PNb Short Code CDMA Techniques & Technologies  Short code is a PN sequence with period of 2 15 chips  Sequence with different time offset is used to distinguish different sectors  Minimum PN sequence offset used is 64 chips, that is, 512 PN offsets are available to identify the CDMA sectors (2 15 /64=512). Walsh Code W 2n = W n W n W n W n W 1 =0 W 2 = 0 0 0 1 W 4 = 0 0 0 1 0 0 0 1 0 0 0 1 Walsh code 64-order Walsh function is used as a spreading function and each Walsh code is orthogonal to other. Walsh Code is one kind of orthogonal code. A Walsh can be presented by W i m where i th (row) is the position and m is the order. For example, W 2 4 means 0101 code in W4 matrix CDMA Techniques & Technologies 1 1 1 0  In forward direction, each symbol is spread with Walsh code  Walsh code is used to distinguish the user in forward link  For IS95A/B, in the reverse, every 6 symbols correspond to one Walsh code. For example, if the symbol input is 110011,the output after spreading is W 51 64 (110011=51).  For CDMA2000, in the reverse, Walsh function is used to define the type of channel (RC 3-9) Walsh Code CDMA Techniques & Technologies Variable Walsh codes 64 4 8 16 32 1 2 9600 19200 38400 76800 153600 307200 614400 Data rate -bps- W 0 1 =0 W 0 2 =00 W 1 2 =01 W 0 4 =0000 W 2 4 =0011 W 1 4 =0101 W 3 4 =0110 W 0 8 =00000000 W 4 8 =00001111 W 2 8 =00110011 W 6 8 =00111100 W 1 8 =01010101 W 5 8 =01011010 W 3 8 =01100110 W 7 8 =01101001 ( W 0 16 ,W 8 16 ) ( W 4 16 ,W 12 16 ) ( W 2 16 ,W 14 16 ) ( W 6 16 ,W 14 16 ) ( W 1 16 ,W 9 16 ) ( W 5 16 ,W 13 16 ) ( W 3 16 ,W 11 16 ) ( W 7 16 ,W 15 16 ) The different Walsh codes corresponding to different data rates CDMA Techniques & Technologies Modulation-QPSK I Q I channel PN sequence 1.2288Mcps Q channel PN sequence 1.2288Mcps Baseband filter Baseband filter Cos(2pf c t) Sin(2pf c t) I(t) Q(t) s(t) A 1.2288Mcps: the PN chip rate of the system . After being spread, all the forward channels in the same carrier are modulated by means of QPSK(OQPSK in the reverse), converted into simulation signals and transmitted after clustering. CDMA Techniques & Technologies  Power Control  Handoff  Diversity and RAKE CDMA Techniques & Technologies Power Control Reverse power control  Open loop power control  Closed loop power control  Inner loop power control: 800 Hz  Outer loop power control Forward power control  Message transmission mode:  threshold transmission  periodic transmission  Closed loop power control . CDMA Techniques & Technologies Reverse Open Loop Power Control • The transmission power required by the mobile station is determined by the following factors:  Distance from the base station  Load of the cell  Circumstance of the code channels • The transmission power of the mobile station is relative to its received power. BTS Mobile Reverse Open Loop Power Control BTS BTS Transmitting Power CDMA Techniques & Technologies Reverse Closed Loop Power Control BTS Power Control Bit E b /N t Value FER Value Inner Loop Power Control Outer Loop Power Control Change in E b /N t Value CDMA Techniques & Technologies BSC BTS Forward Power Control  MS measures the frame quality and informs the base station to the result i.e. whether it is in the threshold or periodical mode. Base station determines whether to change the forward transmitting power or not.  In IS-95 system, the forward power control is slow but in CDMA2000 system it is fast. CDMA Techniques & Technologies Message Transmission Mode Forward Closed Loop Power Control  Compared with IS-95 system, CDMA2000 the forward quick power control is fast. Power Control Bit E b /N t Value CDMA Techniques & Technologies BTS Handoff Soft handoff It is a process of establishing a link with a target sector before breaking the link with the serving sector Softer handoff Like the soft handoff, but the handoff is occurred between multi-sectors in the same base station Hard handoff Hard handoff occurs when the two sectors are not synchronized or are not on the same frequency. Interruption in voice or data communication occurs but this interruption does not effect the user communication CDMA Techniques & Technologies Soft/Softer Handoff • Multi-path combination in the BSC during soft handoff • Multi-path combination in the BTS during softer handoffs Combine all the power from each sector Power received from a single sector CDMA Techniques & Technologies Pilot Set Active Set Candidate Set Neighbor Set Remaining Set The pilot set, corresponding to the base station being connected The pilot set, not in the active set but potential to be demodulated The pilot set, not included in the active set or the candidate set but being possible to be added in the candidate set Other pilot sets the set of the pilots having same frequency but different PN sequence offset CDMA Techniques & Technologies T_ADD,T_DROP,T_TDROP Time Ec/Io Sector A Sector B Guard Time(T-TDROP) Add Threshold (T_ADD) DropThreshold (T_DROP) Soft Handoff Region T_ADD, T_DROP and T_TDROP affect the percentage of MS in handoff. T_ADD & T_DROP is the standards used to add or drop a pilot. T_DROP is a timer. CDMA Techniques & Technologies Comparison Threshold Pilot P1 Pilot P2 Pilot P0 t0 T_COMP×0.5dB t1 t2 T_ADD Pilot strength P0-Strengh of Pilot P0 in Candidate Set. P1,P2-Stength of Pilot P1,P2 in Active Set. t0-Pilot strength Measurement Message Sent, P0>T_ADD t1-Pilot strength Measurement Message Sent, P0>P1+T_COMP*0.5dB t2 -Pilot strength Measurement Message Sent, P0>P2+T_COMP*0.5dB CDMA Techniques & Technologies Transition Between Pilot Sets T_ADD T_DROP Pilot 1 Pilot strength Pilot 2 T_TDROP T_TDROP Neighbor Set Candidate Set Active Set Candidate Set Neighbor Set TIME 1 2 3 4 5 6 7 8 CDMA Techniques & Technologies Transmit Diversity  Time diversity  Block interleaving, error-correction  Frequency diversity  The CDMA signal energy is distributed on the whole 1.23MHZ bandwidth.  Space diversity  The introduction of twin receive antennas .  The RAKE receivers of the mobile station and the base station can combine the signals of different time delay.  During a handoff, the mobile station contacts multiple base stations and searches for the strongest frame CDMA Techniques & Technologies Transmission Diversity The forward transmission diversity types in CDMA2000 1X are TD (Transmit Diversity) OTD (Orthogonal Transmit Diversity) – The data stream is divided into two parts, which will be spread by the orthogonal code sequence, and transmitted by two antennas. STS (Space Time Spreading) – All the forward code channels are transmitted by the multi- antennas. – Spread with the quasi-orthogonal code Non-TD CDMA Techniques & Technologies Transmission Diversity The Transmission Diversity Technology enhances the receive performance of MS. Transmission diversity processing Data stream 1 Data stream 2 Data stream Restoring data stream Antenna 2 Antenna 1 CDMA Techniques & Technologies The Principle of RAKE Receiver RAKE antennas help to overcome on the multi-path fading and enhance the receive performance of the system Receive set Correlator 1 Correlator 2 Correlator 3 Searcher correlator Calculate the time delay and signal strength Combiner The combined signal t t s(t) s(t) CDMA Techniques & Technologies Course Contents Chapter 1 Introduction Chapter 2 CDMA Techniques & Technologies Chapter 3 CDMA Air interface Chapter 4 CDMA Core Network Chapter 5 CDMA Number Planning Physical Channel in IS-95A Forward channel  Forward Pilot Channel  Forward Sync Channel  Forward Paging Channel  Forward Traffic Channel (including power control sub- channel) Reverse channel  Access Channel  Reverse Traffic Channel CDMA Air Interface Pilot channel (all-zeros) W 0 64 Pilot Channel A pilot channel:  Assist mobile station to be connected with CDMA network  Handles multi-path searching  Provide the phase reference for coherent demodulation and help the mobile station estimate the transmission power  The mobile station measures and compares the pilot channel powers from the base stations during the handoff Forward pilot channel is spread over W0 and modulated with short code directly BTS transmits the pilot channel continuously CDMA Air Interface T o Q P S K c o d e r 2.4kbps 4.8kbps 4.8kbps Code symbol Repetitive code symbol 1.2kbps Convolution encoder r=1/2,K=9 symbol repetition Block interleaving Sync Ch bits W 32 64 Sync Channel  The sync channel is used by the mobile station to synchronize with the network. W 32 is used to spread Sync Channel.  The synchronization message includes:  Pilot PN sequence offset: PILOT_PN  System time: SYS_TIME  Long code state: LC_STATE  Paging channel rate: P_RAT  Here note that, sync channel rate is 1200bps CDMA Air Interface T o Q P S K c o d e r Paging channel bits 19.2/9.6Kbps 19.2kbps 19.2kbps Code symbol 9.6/4.8 kbps Convolution encoder r=1/2,K=9 Symbol repetition Block interleaving Paging channel address mask Long code PN generator decimator 1.2288Mcps 19.2kbps Repetitive code symbol Paging Channel  The paging channel transmits:  System parameters message  Access parameters  Neighbors list  CDMA channels list message  The paging channel accomplishes:  Paging to MS  Assign traffic channel to MS  The frame length of a paging channel is 20ms  W 1 ~ W 7 are spared for the Paging Channels spreading CDMA Air Interface W 1 64 Forward Traffic Channel I Ch PN sequence (1.2288 Mcps) PN 1.2288 Mcps Repetitive symbol 19.2kbps 8.6kbps 9.6 kbps 4.8kbps 2.4kbps 1.2kbps Add frame quality indicator bits(12,10,8,6) Add 8 encoded tail bits Convolution encoder r=1/2,K=9 Symbol repetition Forward traffic channal (172/80/40 or 16bits/frame) Block interleaver 19.2kbps MUX Long code generator Power control bits Q Ch PN sequence (1.2288 Mcps) Baseband filter I(t) Q(t) decimator + ∑ QPSK Modulation 4.0kbps 2.0kbps 0.8kbps 19.2ksybps 9.6ksybps 4.8ksybps 2.4ksybps Sin(2pf c t) Cos(2pf c t) is used to transmit data and signaling information. Walsh code CDMA Air Interface decimator + + Baseband filter + + Reverse Access Channel 4.8 kbps (307.2kbps) PN chips 1.2288 Mcps Orthogonal spreading Repetitive symbol 8.8 kbps Code symbol 14.4 kbps 4.4 kbps 4.8 kbps Add 8 encoder tail bits Convolution encoder r=1/3,K=9 Symbol repetition Access channel (80 bits/frame) Block interleaving 28.8 kbps Data burst randomizer Long code PN generator Frame rate Long code mask Repetitive symbol used by MS to initiate communication or respond to Paging Channel Walsh code CDMA Air Interface I Ch PN sequence (1.2288 Mcps) Baseband filter I(t) Q(t) ∑ QPSK Modulation Sin(2pf c t) Cos(2pf c t) + + Baseband filter + + Q Ch PN sequence (1.2288 Mcps) 1/2 PN chips Delayed time=406.9ns Reverse Traffic Channel used to transmit data and signaling information CDMA Air Interface 8.6kbps 9.6 kbps 4.8kbps 2.4kbps 1.2kbps Add frame quality indicator bits(12,10,8,6) Add 8 encoded tail bits convolution encoder r=1/3,K=9 Symbol repetition Reverse traffic channel (172/80/40 or 16 bits/frame) Block interleaver 4.0kbps 2.0kbps 0.8kbps 28.8Ksybps 14.4Ksybps 7.2Ksybps 3.6Ksybps 4.8 kbps (307.2kbps) PN chips 1.2288 Mcps Orthogonal spreading Data burst randomizer Long code PN generator Frame rate Long code mask Walsh code I Ch PN sequence (1.2288 Mcps) Baseband filter I(t) Q(t) ∑ QPSK Modulation Sin(2pf c t) Cos(2pf c t) + + Baseband filter + + Q Ch PN sequence (1.2288 Mcps) 1/2 PN chips Delayed time=406.9ns Initialization of the MS  Synchronous Channel message contains the LC_STATE, SYS_TIME, P_RAT, and synchronizes with the system. CDMA Air Interface BTS CDMA2000 Forward Channel Forward CDMA2000 channel F-CACH F-CPCCH F-PICH F-CCCH F-DCCH F-FCH F-PC F-SCCH F-SCH F-PICH F-TDPICH F-APICH F-ATDPICH F-SYNCH F-TCH F-BCH F-PCH F-QPCH subchannel (RC1~2) (RC3~9) Note: Only the channels with black color are being implemented in Huawei equipment. The function of F-PICH, F-SYNCH, F-FCH, F-PC, F-SCCH, F-PCH are the same as those of IS95. We will only discuss F-SCH, F-QPCH F-DCCH in the following slides. CDMA Air Interface Forward channel These channels are newly defined in CDMA2000 system. CDMA physical channels are classified in common channels and dedicated channels: Common physical channels: Forward Pilot Channel(F-PICH) Forward Synchronous Channel(F-SYNC) Forward Paging Channel(F-PCH) Forward Broadcast Control Channel(F-BCCH) Forward Quick Paging Channel(F-QPCH) Forward Common Power Control Channel(F-CPCCH) Forward Common Assignment Channel(F-CACH) Forward Common Control Channel(F-CCCH) These channels are compatible with IS-95 system Dedicated physical channel: Forward Dedicated Control Channel(F-DCCH) Forward Fundamental Channel(F-FCH) Forward Supplemental Channel(F-SCH) These channels are used to establish the connection between a base station and a specific mobile station. The CDMA2000 system adopts multiple data rates and the different combinations of channels can achieve a performance superior to that in IS-95 system. CDMA Air Interface F-QPCH  It transmits OOK-modulated signal which can be demodulated by MS simply and rapidly.  The channel adopts 80ms as a QPCH timeslot. Each timeslot is divided into paging indicators, configuration change indicators and broadcast indicators, all of which are utilized to inform the MS whether to receive paging message, broadcast message or system parameters in the next F-PCH.  Rapid and simple demodulation. MS no need to monitor F-PCH for long time, so the standby time is prolonged. CDMA Air Interface F-SCH  F-SCH is typically used for high speed data applications, while F-FCH is used for common voice and low speed data application.  When a data call is established, firstly, F-FCH will be allocated to the user. If the speed of data for user exceeds 9.6kbps, F-SCH will be allocated. CDMA Air Interface F-DCCH  It is used for the transmission of specific user signaling information during a call.  Each forward traffic channel may contain one F-DCCH.  Support 5ms frame.  Support discontinuous transmission. CDMA Air Interface Forward Radio Configuration (RC) Radio Configuration(RC): A set of Forward Traffic channel and Reverse Traffic Channel transmission formats that are characterized by physical parameters such as data rates, modulation characteristics, and spreading rate. Spreading Rate: Equivalent to chips rate, e.g., 1.2288Mcps. Radio Configuration Spreading Rate Max Data Rate* (kbps) Effective FEC Code Rate OTD Allowed FEC Encoding Modulation 1** 1 9.6 1/2 No Conv. BPSK 2** 1 14.4 3/4 No Conv BPSK 3 1 153.6 1/4 Yes Conv and Turbo QPSK 4 1 307.2 1/2 Yes Conv and Turbo QPSK 5 1 230.4 3/8 Yes Conv and Turbo QPSK 6 3 307.2 1/6 Yes Conv and Turbo QPSK 7 3 614.4 1/3 Yes Conv and Turbo QPSK 8 3 460.8 1/4 or 1/3 Yes Conv and Turbo QPSK 9 3 1036.8 1/2or 1/3 Yes Conv and Turbo QPSK ** Same as IS95 CDMA Air Interface Reverse Channel Reverse CDMA2000 channel R-ACH R-TCH operation (RC1~2) R-EACH operation R-CCCH operation R-SCCH R-FCH R-TCH operation (RC3~6) R-EACH R-PICH R-CCCH R-PICH R-DCCH R-PICH 0~7 0~1 R-SCH R-FCH 0~2 0~1 subchannel R-PC Only the channels in dark color are used in Huawei equipment. The function of R-ACH,R-FCH,R-SCCH are the same as those in IS95. We will only discuss R-PICH,R-SCH in the following slides. CDMA Air Interface Types of Reverse Channel Reverse channel includes reverse common channel and reverse dedicated channel.  Reverse common channel:  Reverse Access Channel(R-ACH)  Reverse Enhanced Access Channel(R-EACH)  Reverse Common Control Channel(R-CCCH)  Reverse Dedicated Channel  Reverse Pilot Channel(R-PICH)  Reverse Dedicated Control Channel(R-DCCH)  Reverse Fundamental Channel(R-FCH)  Reverse Supplemental Channel(R-SCH)  Reverse Supplemental Code Channel (R-SCCH) CDMA Air Interface MUX A Pilot( all '0's) Power Control Bit N is the Spreading Rate number Pilot Power Control Power Control Group = 1536 NPN Chips 384 NPN Chips Reverse Pilot Channel R-PICH  The Function of Reverse Pilot Channel  Initialization  Tracing  Reverse Coherent Demodulation  Power Control Measurement  Base station enhances the received performance and increases the capacity by means of coherent demodulation of the Reverse Pilot Channel. CDMA Air Interface Reverse Channels Fundamental Channel:  Fundamental Channel is used for the transmission of user information to the base station during a call, and can be used to transmit defaulted voice services as an independent Traffic Channel. Dedicated Control Channel  The Dedicated Control Channel is used for the transmission of user and signaling information to a base station during a call. Supplemental Channel/Supplemental Code Channel  These channels are used for the transmission of user information, mainly data services, to the MS. The Reverse Traffic Channel contains up to two supplemental channels and up to seven supplemental code channels. CDMA Air Interface Reverse Radio Configuration (RC)  RC: Radio Configuration  RC1~RC2:IS-95A/B  RC3~RC4:CDMA2000 1X  RC5~RC6: CDMA2000 3x Radio Configuration Spreading Rate Max Data Rate* (kbps) Effective FEC Code Rate OTD Allowed FEC Encoding Modulation 1** 1 9.6 1/3 No Conv 64-ary ortho 2** 1 14.4 1/2 No Conv 64-ary ortho 3 1 153.6 1/4 Yes Conv or Turbo BPSK (307.2) (1/2) 4 1 230.4 3.8 Yes Conv or Turbo BPSK 5 3 153.6 1/4 Yes Conv or Turbo BPSK (614.4) (1/3) 6 3 460.8 1/4 Yes Conv or Turbo BPSK (1036.8) (1/2) ** Same as IS95 CDMA Air Interface RC 1 RC 2 RC 3 RC 4 RC 5 RC 1 RC 2 RC 3 RC 4 RC 5 RC 3 RC 4 RC 4 RC 3 F-FCH RCs R-DCCH/SCH RCs F-DCCH/SCH RCs R-FCH RCs RC Combination Regulation  RC1 and RC2 corresponds respectively to rate set 1 and rate set 2 in IS- 95A/B system.  CDMA2000 Forward RC: RC1~RC5 Reverse RC: RC1~RC4  Rules:  Forward RC1, Reverse RC1  Forward RC2, Reverse RC2  Forward RC3 or RC4,Reverse RC3  Forward RC5, Reverse RC4 CDMA Air Interface Course Contents Chapter 1 Introduction Chapter 2 CDMA Techniques & Technologies Chapter 3 CDMA Air Interface Chapter 4 CDMA Core Network Chapter 5 CDMA Number Planning A typical CDMA Network MS BS MSC HLR AC EIR VLR PSTN ISDN MC Um A B C D E H Ai Di MSC F VLR MC SME SME G N M M M Q SCP SCP SSP Ai T1 T8 IP HLR IP ISDN Di T2 T 3 T 5 T 9 CDMA Core Network CDMA Interfaces MSC: Mobile-service Switching Center BSC: Base Station Controller MC: Short Message Center HLR: Home Location Register BTS: Base Transceiver Station VM: Voice Mailbox VLR: Visitor Location Register OMC: Operation & Maintenance Center AC: Authentication Center SCP: Service Control Point Other MSCs MC/VM MSC/SSP/VLR OMC HLR/AC SDH GMSC/SSP SCP STP IOS4.0 SS7 IS-41 IS-41 IS-41 IS-41 Mobile Customer Service Center SS7 TCP/IP SS7 IS-41 BTS BTS BSC MS IS95---- CDMA2000 INTERNET Other PLMNs PSTN/ISDN CDMA Core Network PDSN Network Interface MSC/VLR GMSC HLR/ AuC PDSN PSTN GPRS IP 骨干网 SS7 SCP BSS HA A1/A2 BSSAP SCCP MTP Physical layer IP backbon e network A10/A11 A11 signaling UDP IP Linklayer Physical layer A10 service GRE IP Linklayer Physical layer CN CDMA Core Network CDMA Services Businesses, enterprises •Mobile virtual private network •Mobile high-speed network access •Advertising services •Free phone Family •Familiarity number •Life & amusement Schools, groups •Universal account number •Sectorized and time- shared charge •Broadcast news Individuals •Individualized services •Privacy CDMA Core Network CDMA Feature Services---Example 1 Where is my mobile phone? It is lucky to have Ruyi lock! Ruyi lock Features: a mobile phone user can dial the access code and input the PIN code to lock/unlock his mobile phone by using any fixed telephone instead of registering and paying at a business hall. Why can’t I make a call the moment I picked it up? CDMA Core Network CDMA Feature Services---Example 2 FOLLOW ME Features: a user can activate call forwarding of his/he MS from any phone to ensure that any incoming call of a mobile phone user will not be lost. You can register for a forwarding service on your own I forgot to bring my mobile phone, but I will have an important customer to meet this afternoon. What should I do? CDMA Core Network CDMA Feature Services---Example 3 Does that guy still bother you recently? He can no longer reach me! Why? Ask me to input a password? Friendshipcom Features: After a called user subscribes for this service, the system requires password to caller. A call is accomplished only if the password is correct. Otherwise, the call will be rejected or transferred. CDMA Core Network CDMA Feature Services---Example 4 Intra-group user LOOK FOR service Feature 1: When a user makes a call to an intra-group user, the terminals of all intra-group users ring in-turn or simultaneously until there is a reply. CDMA Core Network CDMA2000---Data Services 0 32 64 9.6 128 144 384 2,000 Video Streaming Voice Text Messaging Still Imaging Audio Streaming Electronic newspaper High-quality videoconference Telephone (Voice) Voice Mail E-Mail Fax Electronic book Sports, news and weather report on demand Singing room Low-quality videoconference JPEG Still Photos Mobile Radio Video Surveillance, Video Mail, Travel Image Data Weather, transportation, news, sports and securities Mobile TV E-commerce Remote Medical Service D a t a r a t e i n K b p s CDMA Core Network 3GPP2 uses the following 3 standards for MS location: Locating Services  GPS-aided measurement  Accuracy: suburbs---10m. City zone---30~70m. Indoor --unable to locate  Response time: 3~10s  Measurement of base station pilot phase  Accuracy: 50~200m  Response time: 3~6s  Locating of a cell ID  Accuracy: depends on the size of a cell  Response time: within 3s CDMA Core Network 110! Bandit!  The system transfers the alarm to the nearest alarm processing center based on the location.  An emergency button can be set on a user’s mobile phone to so that an alarm can be reported without any conversation or delay. Locating Services CDMA Core Network PSTN CDMA/ INTERNET Users who subscribe for toll services Original toll route Toll route after subscription MSC/GMSC HLR Operators who subscribe for toll services  Help mobile operators to absorb large quantities of toll services  Users subscribe to select toll operators to ensure quality of service.  Enable users to save toll call charge (premium strategy)  Make an IP toll call without dialing a preamble Equal Access of Toll Calls CDMA Core Network Course Contents Chapter 1 Introduction Chapter 2 CDMA Techniques & Technologies Chapter 3 CDMA Air Interface Chapter 4 CDMA Core Network Chapter 5 CDMA Number Planning Definition of Coverage Areas Location area MSC area PLMN area Service area Sector area CDMA Number Planning Cell area Parameters Involved In a CDMA system, the following parameters are defined to identify a user and his location: MIN/IMSI  MDN  ESN  TLDN  SID/NID  LAI  GCI  SIN  SSN CDMA Number Planning MIN/IMSI Mobile subscriber identity/international mobile subscriber identity For example, 0907550001/460030907550001 Not more than 15 digits 3 digits 2 digits IMSI MCC MNC MSIN NMSI CDMA Number Planning MDN CC + MAC + H 0 H 1 H 2 H 3 + ABCD International mobile subscriber DN National valid mobile subscriber number Mobile directory number For example, 8613307550001 CDMA Number Planning ESN A unique Electronic Serial Number (ESN) is used to identify single MS. An ESN includes 32 bits and has the following structure: 31......24 23......18 17......0 bit Manufacturer’s number retained equipment SN For example, FD 03 78 0A (the 10th Motorola 378 mobile phone) The equipment serial number is allocated by a manufacturer. CDMA Number Planning TLDN + CC MAC H 0 H 1 H 2 ABC + + + 44 Temporary local directory number For example, 8613344755001 CDMA Number Planning SID/NID MSCID (Exchange Identity) = System Identity (SID) + Exchange number (SWIN) is used to represent a certain set of equipment in an NSS network. For example, Unicom CDMA Shenzhen MSC is labeled as 3755+01 CDMA Number Planning Location Area Identity (LAI) PAGING message is broadcast within a local area, the size of which depends on traffic, paging bearer capability, signaling flow , etc. Format: MCC+MNC+LAC  MCC: Mobile Country Code, 3 digits. For example, China is 460.  MNC: Mobile Network Code, 2 digits. For example, the MNC of Unicom is 03.  LAC: Location Area Code, a 2-byte-long hexadecimal BCD code. 0000 cannot be used with FFFE. For example, 460030100 CDMA Number Planning Global Cell Identity (GCI)  The unique ID of a cell in PLMN  Format: LAI+CI  CI: Cell Identity, a 2-byte-long hexadecimal BCD code, pre defined by the engineering department. The first 3 digits and the last digit represent the base station number and the sector number respectively. For an omni-directional site, the last digit of CI is 0.  For example, 4600301001230 shows base station number 123 contains an omni-directional site CDMA Number Planning Sender Identification Number (SIN) MSC number The MSC number stipulated by Unicom is 460 + 03 + 09 + H0H1H2H3 + 1000. HLR number The HLR number stipulated by Unicom is 460 + 03 + 09 + H0H1H2H3 + 0000. SMC number The SMC number stipulated by Unicom is 460 + 03 + 09 + H0H1H2H3 + 2000. SCP number The SCP number stipulated by Unicom is 460 + 03 + 09 + H0H1H2H3 + 3000. CDMA Number Planning Sub-System Number (SSN  SSN of MSC: 8  SSN of VLR: 7  SSN of HLR: 6  SSN of AC: 10  SSN of SMC: EE  SSN of SCP: EF  SSN of A interface: FE/FC  SSN of SCCP management: 1 CDMA Number Planning Voice Channel Routing TMSC1 TMSC2 MSC TMSC1 MSC TSI international office CDMA Number Planning Signaling Route Level 1 Level 2 Level 3 HSTP&LSTP SP CDMA Number Planning Example of Signaling Network Route from an LSTP to the LSTP not located in the same place HLR in Chongqin to MSC in Fujian (two LSTPs respectively at the transmit end and receive end) H1 in Chengdu H1 in Shanghai H2 in Chongqin H2 in Shanghai L1 in Chongqin L2 in Chongqin L1 in Fuzhou L2 in Fuzhou HLR in Chongqin MSC in Fuzhou CDMA Number Planning Interconnection of CDMA with PSTN Mobile telephone network Tm DC2 DC1 LS MSC MS BTS BSC TMSC2 Primary ring of a local network PSTN Toll network Local network TMSC1 Mesh interconnection Mesh interconnection TMSC1 MSC BTS BSC TMSC2 Primary ring of a local network Tm DC2 HSTP LSTP SP LSTP HSTP HSTP LSTP LSTP SP SP SP DC1 LS MS PSTN CDMA Number Planning Review  Chips rate: 1.2288Mcps  IS-95A/B is a subset, RC1/RC2  Apply the coherent demodulation to the reverse pilot channel  Forward transmit diversity: OTD and STS  Forward quick power control at 800HZ rate  Improve the standby time by introducing the quick paging channel.  Variable frames: 5ms, 20ms, 40ms and 80ms  Introduce TURBO code into channel encoding  The maximum rate of a physical layer is up to 307.2K CDMA Technology Development of CDMA Standards in China CDMA standards currently adopted in China are mainly based on the USA standards with few alterations. For example, in USA the emphasis is put on the dual service support i.e. CDMA and AMPS compatibility, while in China there is no such requirement. Therefore, the settings of frequency and basic channels, IMSI and others parameters need to be modified. Likewise, there is also the need to modify network interface IS-41 series of standards. Case study: China Unicom Network In China Unicom CDMA project, phase 1, a narrow-band CDMA network, named IS-95B (enhanced IS-95) is being constructed. With total capacity is 15,000,000, subscribers handling, covering over 200 cities. Currently, both nationwide and international roaming tests have conducted successfully with the CDMA networks of HongKong, South Korea and Japan via the TSI international gateway bureau. Besides, a CDMA intelligent network will be constructed to provide intelligent value-added services like Pre-Paid Charging (PPC) and Virtual Private Network (VPN) etc. The whole CDMA20001X network was launched in air in the second half of 2002. Why CDMA2000? Increase the system capacity  Forward quick power control  Forward transmit diversity: OTD,STS  Coherent modulation applied on the pilot channel.(about 3dB)  The introduction to Turbo code  The stronger ability to resist interference The improved error-correcting encoding (applying Turbo code in medium/high rate data transmission) Why CDMA2000? Support high rate SCH, with the maximum rate of a single channel being up to 307.2kbps.  Improve the standby time  Use the quick paging channel Forward compatibility  Radio-frequency part  Baseband part, such as RC Summary Brief Development History of Mobile Communication  Analog--digital--code division  Objectives of 3G and comparison of 3 systems Technical features of CDMA  Key technologies: power control, soft handoff,RAKE receiver and cell breath  Other technologies: source coding, channel coding, interleaving, scrambling, spreading and modulation  Channel structure: pilot, synchronization, paging, access and service Technical features of CDMA2000 1X  Walsh and Turbo codes Questions  What power control modes are there in CDMA2000 system and how are they implemented?  Describe the soft handoff process?  Describe the process and functions of cell breath?  Describe the implementation process of service channels (forward and reverse)?  Describe the technical features of CDMA2000?  Describe the initialization process of a mobile phone?  What are the functions of a long code, short code and Walsh code in CDMA system?
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