About 3GPP W-CDMA Design Library
W-CDMA for the third generation (typically referred to as 3GPP, 3rd Generation Partnership Project ) evolved from the technical proposals from Japan and Europe for third-generation wireless communications. The convergence of 3GPP specifications is based on inputs from global contributors. 3GPP offers service rates up to 2 Mbps. 3GPP is a complete protocol stack covering issues ranging from the physical layer to network control aspects.
This 3GPP design library focuses on the physical layer, which includes the following functionalities.
- Macro diversity distribution/combining and soft hand-over execution
- Error detection on transport channels and indication to higher layers
- Forward error control (FEC) encoding/decoding of transport channels
- Multiplexing of transport channels and demultiplexing of coded composite transport channels
- Rate matching: data multiplexed on dedicated channels (DCHs)
- Mapping of coded composite transport channels on physical channels
- Power weighting and combining of physical channels
- Modulation and spreading/demodulation and de-spreading of physical channels
- Frequency and time (chip, bit, slot, frame) synchronization
- Radio characteristic measurements including frame error rate (FER), signal-to-interference (SIR), interference power level, and indication to higher layers
- Closed-loop power control
- Radio frequency processing
3GPP Technical Specifications Supported
The 3GPP committee updates 3GPP technical specifications every 3 months. The 3GPP FDD design library supports 3GPP release 1999 technical specifications. Those specifications are released in 2000-03, 2000-12, and 2002-03.
Each specification is further classified by features: release 1999 (Version 3.xx), release 4 (Version 4.xx) and release 5 (Version 5.xx). Basically, the contents defined in lower version specifications typically duplicate the contents from release 1999 and release 4 that are published simultaneously. Most features supported by the 3GPP FDD design library are release 1999 features; limited release 5 features are available such as the downlink HSDPA signal source provided in TestModel5 and uplink HS-DPCCH transmitter/receiver models. The HSDPA specification version is September 2003.
Agilent Instrument Compatibility
This 3GPP design library is also compatible with Agilent E4406A VSA Series Transmitter Tester, Agilent PSA Series High-Performance Spectrum Analyzer, and Agilent 89600 Series Vector Signal Analyzer.
The following table shows more information of instrument models, Firmware revisions, and options.
Agilent Instrument Compatibility Information
3GPP Design Library
E443xB, Firmware Revision B.03.86
E4406A, Firmware Revision A.04.21 (and later)
For more information about Agilent ESG Series of Digital and Analog RF Signal Generator and Options, please visit
For more information about Agilent E4406A VSA Series Transmitter Tester and Options, please visit
For more information about Agilent PSA Series Spectrum Analyzer and Options, please visit
For more information about Agilent 89600 Series Vector Signal Analyzer and Options, please visit
Physical Layer Transmitter and Receiver Structures
The downlink transmitter and receiver structures, based on the behavioral models and systems, are illustrated in the following figures.
Downlink Transmitter Structure
Downlink Receiver Structure
The uplink transmitter and receiver structures are illustrated in the following figures.
Uplink Transmitter Structure
Uplink Receiver Structure
The WCDMA3G Design Library includes key features of a 3GPP system.
- Variable rate services
- Standard slot format including TPC, TFCI, FBI and pilot bits multiplexing
- Standard frame format
- Turbo coding/decoding and convolutional coding/decoding
- Multiplexing of different transport channels (TrCHs) onto one coded composite transport channel (CCTrCH)
- Support of fixed and flexible positions of TrCHs in one CCTrCH frame
- Support of transport format detection with transport format combination indicator (TFCI)
- Support of space time transmit diversity (STTD) encoding
- Synchronization based on common pilot channel
- Multipath searching
- Standard Rake receiver with maximum ratio combining (MRC)
- Linear channel estimation with interpolation
- Coherent QPSK demodulation
- Power control
General Signal Processing
Generally, a single data stream from the TrCH multiplexing model is denoted as the CCTrCH. One CCTrCH is mapped onto M DPCHs. The spread signal is then scrambled and mapped to the I and Q channel.
Each variable rate service model serves as a transport channel that generates a variable rate date source that changes every 10 ms. Only one transport block set is generated during each TTI. The transport formats (TF) of N TrCHs are mapped into a TFCI value by TFCI Mapper.
Framing of each transport block is done by performing cyclic redundancy check (CRC) to each transport block. The parity bits of CRC are 24, 16, 12, 8 or 0 depending on signalling from higher layers.
After framing, all transport blocks in one TTI are serially concatenated and segmented into channel coding blocks. The code blocks after segmentation are the same size, which is less than a predetermined value based on the channel coding type. Code blocks are delivered to channel coding models.
Bit streams of all TrCHs after channel coding are transferred to a rate matching model. Rate matching is necessary for supporting variable rate source of DCH. Bits on a TrCH can be repeated or punctured after rate matching. Higher layers assign a rate-matching attribute for each transport channel, which is used to calculate the number of bits to be repeated or punctured. For downlink, rate matching matches the bits of all TrCHs in 10 ms to the total number of bits that are available for the CCTrCH in a radio frame. With the fixed positions of TrCHs, a fixed number of bits is reserved for each TrCH in the radio frame of CCTrCH. If the bits of one TrCH after rate matching fill all allocated bit positions, DTX indication bits must be inserted.
The output bit streams after the first interleaver are segmented into radio frames. The first interleaver is a block interleaver with inter-column permutations. When the TTI is longer than 10 ms, the input bit sequence is segmented and mapped onto consecutive radio frames; the number of bits in each radio frame is same.
Every 10 ms, one radio frame from each TrCH is delivered to the TrCH multiplexing model. These radio frames are serially multiplexed into one frame of CCTrCH. With flexible positions of TrCHs, any DTX indication bits are placed at the end of the CCTrCH radio frame. Bit streams from one CCTrCH will then be mapped onto several DPCHs (consisting of DPDCH and DPCCH). When more than one DPCH is used, physical channelization is implemented by using orthogonal codes.
Second interleaving is performed between DPCH frames. The second interleaving is a block interleaver with inter-column permutations. Control information bits, such as TPC commands and an optional TFCI, are mapped onto DPCCH. Data modulation, spreading, and scrambling are then performed
At the receiver side, coherent demodulation and MRC combining require the channel estimate information, which is obtained by the channel estimate model. The path searching model discriminates the delay between multipath signals, the delay information is fed into the standard Rake receiver model to perform multipath signal combining.
The soft output from the Rake receiver is used by turbo/convolutional decoder to further improve the reliability of received information. De-framing and de-multiplexing are performed symmetrically as the framing and multiplexing procedures and the transmitted signals are recovered.
Overview of Component Libraries
Channel Coding Components
Channel coding components accomplish the following functions.
- The cyclic redundancy check (CRC) provides error detection of the transport blocks for a particular transport channel. The CRC can take 0 (no CRC), 8, 12, 16, or 24 bits depending on service requirements. CRC coding and decoding are performed.
- Convolutional coding is applied to real time services such as speech. The Viterbi algorithm is used to obtain optimum performance.
- Turbo coding provides near-optimum performance. Non-realtime services use turbo coding to reduce the radio resource consumptions. Most models in this group used for turbo coding take into account its parallel encoding and iterative decoding nature. Some tail bits are padded in the encoding side to assist the decoder to properly terminate the decoding trellis, which enhances performance. Internal turbo coding interleaving and de-interleaving algorithms are also implemented.
- TFCI Reed-Muller (RM) coding. TFCI is important for the receiver to properly de-segment the recovered bit streams into transport channels. TFCI is protected by RM codes.
- Interleaving is used to spread burst errors into random errors in order to improve the error correction code performance. There are two interleaving algorithms in 3GPP: one is used for individual transport channels; one is used between different transport channels.
- To simplify the top-level appearance, two sets of models have been grouped as two subnetwork models: WCDMA3G_ChannelCoding and WCDMA3G_ChannelDecoding. When setting up a completed channel coding function, the use of these models is simpler than grouping a number of individual models to accomplish the desired function.
Channel Model Components
Two methods are available to simulate multi-path fading. The first method passes a Gaussian random noise through a filter whose frequency response is identical to classical Doppler fading; the second method is the sum-of-sinusoids methods in which the phase shift for each single sinusoid signal can be deterministic according to the traditional Jake model, or statistical following a recently published academic paper. Both methods are implemented in the Fader component located in the Antenna & Propagation library; refer to Fader documentation for more information.
The new 3GPPFDD_Channel subnetwork design is based on Fader to simulate a 3GPP multipath fading channel.
Beginning with 2003C, the five models provided in the 3GPPFDD 10-99 Channel Model library are obsolete for new applications (WCDMA3G_CHDelay, WCDMA3G_CHInterpolate, WCDMA3G_CHModel, WCDMA3G_ClassicalChannel, and WCDMA3G_UserDefinedCH). These models can still be used; however, for new applications the 3GPPFDD_Channel subnetwork (available in the 3GPPFDDD Channel Model library) is recommended.
Common Physical Channels Components
This group is used to process common physical channels, such as common pilot channel and SCH for downlink. These channels are used to implement timing and synchronizations specifically for base station identification, and frame and slot synchronization.
Variable data source generators are located in this group. The three kinds of data sources are:
- Broadcast channel source used for broadcast channels
- Fixed rate data source used for measurement channels
- Variable rate data source provides a variable rate bit stream to test the capability of 3GPP to support variable rate service
BER and FER measurement models are used to obtain the required system performance measurement. These models provide designers maximum flexibility to conveniently obtain the measurements.
To measure the performance of power control algorithm, the WCDMA3G_TxPowAdjust and WCDMA3G_PowCtrlCmd models facilitate power control implementation. WCDMA3G_PowerMeasure is used to measure power of the transmitted signal.
Physical Channel Multiplex Components
Models in this group are used to perform segmentation and de-segmentation between CCTrCH and physical channels. This includes packaging control bits and user data into the standard frame structure and vice-versa.
Rake Receiver Components
A path-search model is used to resolve the overlapped signals transmitted over a multi-path channel. Signals with different delays are then down-sampled at the proper instant to eliminate inter-symbol interference. The down-sampled signals are de-spread and combined according to channel information obtained from the channel estimation. The combining rule is called maximum-ratio combining .
Spreading and Modulation Components
The 3GPP channelization codes are called OVSF, which is an index-permuted Walsh code. Downlink and uplink OVSF allocations are performed by WCDMA3G_DnLkOVSFAlloc and WCDMA3G_UpLkOVSFAlloc. The OVSF spread signals are then scrambled by downlink and uplink scramble codes.
Downlink QPSK modulation and spreading and uplink spreading are also in this group. WCDMA3G_UpLkGainFactor gives gain quantized factors to DPDCH and DPCCH channels. Where multiple physical channels are used in downlink, only the first physical channel is used to carry the control bits, such as TPC and TFCI bits. These bits are transmitted at high power levels; WCDMA3G_DnLkPowerAlloc is used to adjust their gains.
Transmit Diversity Components
STTD encoding is implemented in the WCDMA3G_STTDEncoder. WCDMA3G_STTDMux is used to insert the necessary pilot symbols into the STTD encoded signals.
Transport Channel Multiplex Components
Models in this group are used to perform transport channel processing in accordance with 3GPP specifications; including implementation of the rate matching algorithm.
Base Station and User Equipment Components
To reduce the efforts in setting up common parts of a 3GPP system, a number of model sets have been grouped as independent models. Instead of placing and connecting a number of individual models, a reference system can be set up easily by using the models in these groups.
Base Station Components
Models in this group accommodate implementation of specific macro-functions for downlink, including fixed-rate signal source, variable signal source, receiver for fixed- and variable-rate signals with and without channel coding.
Other common channels and functions are also implemented as independent models, such as CPICH, PCCCH, transport channel coding and decoding. These are particularly helpful for designers whose focus is not on baseband signal processing.
User Equipment Components
Models in this group accommodate implementation of specific macro-functions for uplink, including fixed-rate signal source, variable signal source, receiver for fixed- and variable-rate signals with and without channel coding.
Other common channels and functions are also implemented as independent models.
Components with the 3GPPFDD prefix are compliant with 3GPP technical specifications after October 1999 and support arbitrary transport channel configurations; these components are in the 3GPPFDD library category. (Components that are compliant with 3GPP technical specifications of October 1999 are in the 3GPPFDD 10-99 library category.) The 3GPP version specification can be selected by the SpecVersion parameter that is listed ahead of all other parameters.
The RF characteristics can be measured using the 3GPP W-CDMA Design Library. RF measurements for user equipment (UE) are defined in ; test methods are described in . For base station (BS), the RF characteristic are defined in ; test methods are described in .
The RF Measurement Example designs are provided with the 3GPP W-CDMA Design Library in the / examples/wcdma3g directory. This documentation describes the examples and includes schematics and simulation results. Projects and their corresponding design examples are listed here.
There are two sets of signal source models in the 3GPP Design Library. Components that are compliant with 3GPP technical specifications of October 1999 are in the 3GPPFDD 10-99 library category. Components in the 3GPPFDD library category support three 3GPP specification versions: March 2000, December 2000, and March 2002. These can be selected by the SpecVersion parameter. These components are used to update the following application projects:
Compared with the previous release, the signal source and receiver, as well as the measurement sub-system have been replaced by new integrated 3GPP models for Tx/Rx characteristic test examples. The IF parts have been removed from the Tx/Rx tests.
The WCDMA3G_BERValidation_prj contains two designs to test 3GPP channel coding performance over AWGN channel and two designs to test 3GPP performance over fading channel.
The WCDMA3G_BS_Rx_prj project shows base station receiver measurement characteristics. Designs for these measurements include:
- Adjacent channel selectivity: BS_Rx_ACS.dsn
- Blocking characteristics: BS_Rx_Blocking.dsn
- Dynamic range: BS_Rx_DynamicRange.dsn
- Intermodulation characteristics: BS_Rx_Intermod.dsn
- Reference sensitivity levels: BS_Rx_RefLevel.dsn
The WCDMA3G_BS_Tx_prj project shows base station transmitter measurement characteristics. Designs for these measurements include:
- Adjacent channel leakage power measurements in frequency domain: BS_Tx_ACLR.dsn
- Complementary cumulative distribution function measurements: BS_Tx_CCDF.dsn
- Signal power distribution measurements in code domain: BS_Tx_Code_Domain_Power.dsn
- Transmitter EVM measurements: BS_Tx_EVM.dsn
- Maximum power measurements: BS_Tx_MaxPower.dsn
- Occupied bandwidth measurements: BS_Tx_Occupied_BW.dsn
- Transmitter peak code domain error measurements: BS_Tx_Pk_Code_Error.dsn
- Transmitter spectrum emissions measurements: BS_Tx_Spec_Emission.dsn
- Spurious emissions measurements: BS_Tx_SpurEmission.dsn
The WCDMA3G_UE_Rx_prj project shows 3GPP W-CDMA user equipment receiver measurements. Designs for these measurements include:
- Adjacent channel selectivity: UE_Rx_ACS.dsn
- Intermodulation characteristics: UE_Rx_Intermod.dsn
- Maximum input levels: UE_Rx_MaxLevel.dsn
- In-band blocking characteristics: UE_Rx_In_Band_Blocking.dsn
- Reference sensitivity levels: UE_Rx_RefLevel.dsn and UE_Rx_RefLevel_Without_IF.dsn
The WCDMA3G_UE_Tx_prj project demonstrates user equipment transmitter measurement characteristics. Designs for these measurements include:
- Adjacent channel leakage power ratio measurements: UE_Tx_ACLR.dsn and UE_Tx_ACLR_SwitchingTransients.dsn
- CCDF and peak-to-mean information measurements: UE_Tx_CCDF.dsn
- Signal power distribution measurements in code domain: UE_Tx_Code_Domain_Power.dsn
- Error vector magnitude measurements: UE_Tx_EVM.dsn
- Maximum power measurements: UE_Tx_Max_Power.dsn
- Occupied bandwidth measurements: UE_Tx_Occupied_BW.dsn
- Peak code domain error measurements: UE_Tx_Pk_Code_Error.dsn
- Spectrum emission measurements: UE_Tx_Spec_Emissions.dsn
- Spurious Emission: UE_Tx_SpurEmission.dsn
The WCDMA3G_SignalSource_prj project provides file-based signal sources for other measurements as well as EVM measurement examples. There are also designs demonstrating interface with ESG and VSA instruments.These examples are:
- Downlink Test Model 1 Signal Source: 3GPPFDD_BS_Tx_TestModel1.dsn
- Uplink 12.2 kbps Signal Source: 3GPPFDD_UE_Tx_12_2.dsn
- ESG Option 100 Compliant Signal Source Demo: 3GPPFDD_ESG100_Demo.dsn
- EVM Measurement with Non-Synchronized Signal: 3GPPFDD_EVM_Demo.dsn
- EVM Measurement with Synchronized Signal: 3GPPFDD_EVM_Synch_Demo.dsn
- ESG E4438C interface demo: 3GPPFDD_ESG4438C.dsn
- ESG E443xB interface demo: 3GPPFDD_ESG443xB.dsn
The WCDMA3G_PA_Test_prj project focuses on verification of power amplifier design for 3GP wireless handsets that support two 3GPP specifications. Nine measurements are provided:
- Adjacent channel leakage power ratio measurements: WCDMA3G_PA_UE_ACLR.dsn
- ACLR measurements in presence of switching transients: WCDMA3G_PA_UE_ACLR_SwitchingTransient.dsn
- CCDF and peak-to-mean information measurements: WCDMA3G_PA_UE_CCDF.dsn
- Signal power distribution measurements in code domain: WCDMA3G_PA_UE_CodeDomainPower.dsn
- Error vector magnitude measurements: WCDMA3G_PA_UE_EVM.dsn
- Occupied bandwidth measurements: WCDMA3G_PA_UE_OccupiedBW.dsn
- Maximum power measurements: WCDMA3G_PA_UE_OutputPower.dsn
- Peak code domain error measurements: WCDMA3G_PA_UE_PkCodeError.dsn
- Spectrum emission measurements: WCDMA3G_PA_UE_SpecEmissions.dsn
The WCDMA3G_Export_prj project contains the wireless test benches that are migrated to RFDE design environments.
Release 5 Specifications
- 3GPP Technical Specification TS 25.211, "Physical channels and mapping of transport channels onto physical channels (FDD)," Sept. 2002, Release 5.
- 3GPP Technical Specification TS 25.213, "Spreading and modulation (FDD)," Sept. 2002, Release 5.
- 3GPP Technical Specification TS 25.141, "Base station conformance test," Sept. 2002, Release 5.
Release 1999 Specifications
- 3GPP Technical Specification TS 25.211, "Physical channels and mapping of transport channels onto physical channels (FDD)," Mar. 2000 / Dec. 2000 / Mar. 2002, Release 1999.
- 3GPP Technical Specification TS 25.212, "Multiplexing and channel coding (FDD)," Mar. 2000 / Dec. 2000 / Mar. 2002, Release 1999.
- 3GPP Technical Specification TS 25.213, "Spreading and modulation (FDD)," Mar. 2000 / Dec. 2000 / Mar. 2002, Release 1999.
- 3GPP Technical Specification TS 25.214, "Physical layer procedures (FDD)," Mar. 2000 / Dec. 2000 / Mar. 2002, Release 1999.
- 3GPP Technical Specification TS 25.101, "UE Radio transmission and Reception (FDD)," Apr. 2000 / Dec. 2000 / Mar. 2002, Release 1999.
- 3GPP Technical Specification TS 25.104, "UTRA (BS) FDD: Radio transmission and Reception," Mar. 2000 / Dec. 2000 / Mar. 2002, Release 1999.
- 3GPP Technical Specification TS 25.141, "Base station conformance test," Mar. 2000 / Dec. 2000 / Mar. 2002, Release 1999.
- 3GPP Technical Specification TS 34.121, "Radio transmission and reception (FDD)," Mar. 2000 / Dec. 2000 / Mar. 2002, Release 1999.