EGPRS

EGPRS2 GBSS13.0

Feature Parameter Description

Issue 01

Date 2011-03-31

HUAWEI TECHNOLOGIES CO., LTD.

Copyright © Huawei Technologies Co., Ltd. 2012. All rights reserved.

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GSM BSS

EGPRS2 Contents

Issue 01 (2011-03-31) Huawei Proprietary and Confidential

Copyright © Huawei Technologies Co., Ltd.

i

Contents

1 Introduction ........................................................................................................................... 1-1

1.1 Scope ...................................................................................................................................... 1-1

1.2 Intended Audience ................................................................................................................... 1-1

1.3 Change History ........................................................................................................................ 1-1

2 Overview ................................................................................................................................ 2-1

3 Technical Description.......................................................................................................... 3-1

3.1 Modulation Schemes and Coding Schemes .............................................................................. 3-1

3.1.1 EGPRS2-A Modulation Schemes ..................................................................................... 3-1

3.1.2 EGPRS2-A Coding Schemes ........................................................................................... 3-2

3.2 Link Quality Control .................................................................................................................. 3-3

3.2.1 Overview ......................................................................................................................... 3-3

3.2.2 Uplink EGPRS2-A Coding Scheme Adjustment Algorithm................................................. 3-4

3.2.3 Downlink EGPRS2-A Coding Scheme Adjustment Algorithm ............................................ 3-4

3.3 EGPRS Level Selection and Switching ..................................................................................... 3-5

3.4 Carrier Allocation Algorithm ...................................................................................................... 3-6

3.5 Channel Allocation Algorithm .................................................................................................... 3-6

3.6 Multiplexing of GPRS, EGPRS, and EGPRS2 Capable MSs ..................................................... 3-6

3.7 Data Transmission ................................................................................................................... 3-7

4 Parameters ............................................................................................................................ 4-1

5 Counters ................................................................................................................................ 5-1

6 Glossary ................................................................................................................................. 6-1

7 Reference Documents ......................................................................................................... 7-1

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EGPRS2 1 Introduction



1-1

1 Introduction

1.1 Scope

This document describes the modulation scheme, coding scheme, link quality control, carrier allocation algorithm, and channel allocation algorithm in the EGPRS2 feature.

The features involved are GBFD-510803 Uplink EGPRS2-A and GBFD-510804 Downlink EGPRS2-A.

1.2 Intended Audience

It is assumed that users of this document are familiar with GPRS basics and have a working knowledge of GPRS telecommunication.

This document is intended for:

Personnel working on Huawei GPRS products or systems

System operators who need a general understanding of this feature

1.3 Change History

The change history provides information on the changes in different document versions.

There are two types of changes, which are defined as follows:

Feature change

Feature change refers to the change in the EGPRS2 feature of a specific product version.

Editorial change

Editorial change refers to the change in wording or the addition of the information that was not described in the earlier version.

Document Issues

The document issues are as follows:

01 (2011-03-31)

Draft A (2011-01-15)

01 (2011-03-31)

This is the commercial release of GBSS13.0.

Compared with issue Draft A (2011-01-15) of GBSS13.0, this issue incorporates no change.

Draft A (2011-01-15)

This is the draft release of GBSS13.0.

Compared with issue 01 (2010-06-30) of GBSS12.0, issue Draft A (2011-01-15) of GBSS13.0 has no change.

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EGPRS2 2 Overview



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2 Overview

Currently, the GSM network is the most widely used cellular communication network in the world. To protect the investment of the operators and to attract more subscribers towards the 3G services, the GSM network needs to support a higher data rate during its evolution to WCDMA and LTE. In this case, the enhanced general packet radio service 2 (EGPRS2) is introduced. The EGPRS2 is evolved from EGPRS. It improves the throughput on the downlink and the uplink in the GSM EDGE Radio Access Network (GERAN). EGPRS2 uses such technologies as high order modulation, high symbol rate (HSR), and Turbo codes to obtain higher uplink and downlink data rates than the EGPRS.

EGPRS2 is an evolution of the EGPRS function. By implementing the high order modulation, HSR, and Turbo codes, EGPRS2 obtains higher uplink and downlink data rates than EGPRS. EGPRS2 is classified into EGPRS2-A and EGPRS2-B.

EGPRS2-A: In the downlink direction, EGPRS2-A increases the data rate by using the Turbo codes and 16 quadrature amplitude modulation (16QAM)/32QAM modulation scheme. In the uplink direction, EGPRS2-A increases the data rate by using the 16QAM modulation scheme. In addition, EGPRS2-A uses the gaussian minimum shift keying (GMSK) and 8 phase shift keying (8PSK) modulation schemes to ensure compatibility with the EGPRS.

EGPRS2-B: In the downlink direction, EGPRS2-B increases the data rate by using the HSR, Turbo codes, and QPSK/16QAM/32QAM modulation scheme. In the uplink direction, EGPRS2-B increases the data rate by using the HSR and QPSK/16QAM/32QAM modulation scheme. In addition, EGPRS2-B uses the GMSK and 8PSK modulation schemes to ensure compatibility with the EGPRS.

Currently, Huawei GBSC supports only EGPRS2-A. In addition, Huawei GBSC supports EGPRS2-A only when IP/HDLC transmission is adopted on the Abis interface. In theory, EGPRS2-A increases the data rate of the PS services in the downlink and uplink respectively to 1.66 times and 1.3 times of that in EGPRS.

In the downlink, the BTS supports the 16QAM and 32QAM modulation schemes. Thus all PDCHs support EGPRS2-A services. In the uplink, the BTS supports only the 16QAM modulation scheme. Thus not all PDCHs support EGPRS2-A services.

The support capability of the uplink EGPRS2-A is restricted by the baseband processing capability of the BTS. That is, the BSC determines the allocation of EGRPS2-A TRXs and channels based on the baseband processing capability reported by the BTS.

To ensure compatibility with the GPRS and EGPRS, the BSC supports the multiplexing of GPRS MS and EGPRS MS on the same PDCH channel with the EGPRS2 MS.

The BSC allocates the EGPRS level to the MS based on the radio access capability of the MS by sending the EGPRS Level message to the MS through the resource allocation procedure. The BSC also supports the switching between EGPRS levels at the same time.

The link quality control algorithm should support EGPRS2-A because new modulation schemes and coding schemes are added to EGPRS2-A. In addition, the radio block format in EGPRS2, coding schemes, retransmission mechanism of radio link control (RLC) data blocks, EGPRS2-A assembly of RLC data blocks, and segmentation of logical link control packet data units (LLC PDUs) in EGPRS2-A should be supported during data transmission.

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EGPRS2 3 Technical Description



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3 Technical Description

3.1 Modulation Schemes and Coding Schemes

3.1.1 EGPRS2-A Modulation Schemes

In the downlink direction, EGPRS2-A uses the Turbo codes and 16QAM/32QAM modulation schemes. In the uplink direction, EGPRS2-A uses the convolutional codes and 16QAM modulation scheme. Symbol rate used on EGPRS2-A uplink/downlink is normal symbol rate (NSR). In addition, EGPRS2-A uses the GMSK and 8PSK modulation schemes to ensure compatibility with the EGPRS.

Compared with the 8PSK and GMSK, the QAM increases the peak cell rate and average bit rate and features higher anti-interference capability. Compared with the convolutional codes, the Turbo codes increase the average bit rate. In addition, the Turbo codes have a higher error correction capability. The combination of Turbo codes and QAM modulation scheme further increase the peak throughput and C/I gain.

Compared with the 8PSK and GMSK, the 16QAM allows lower coding rate (because of the higher modulation bit rate). Thus, the data throughput and C/I gain are increased.

Compared with the 16QAM, the 32QAM has higher peak cell rate. Compared with the 8PSK, the 32QAM obtains a channel coding scheme that is more robust than the existing MCS coding scheme.

The 16QAM uses four modulation bits to map a symbol. The 16QAM has a total of 16 symbols. The 32QAM uses five modulation bits to map a symbol. The 32QAM has a total of 32 symbols. Figure 3-1 shows the signal constellations of the QAM.

Figure 3-1 Signal constellations of the QAM (left: 16QAM; right: 32QAM)

Table 3-1 lists the peak-average ratios (PARs) of different modulation schemes, PAR is the ratio of the peak power to the average power. .

Table 3-1 PARs of different modulation schemes

Modulation Scheme PAR (dB)

8PSK with 3Л/8 rotation 3.3

16QAM 5.9

16QAM with Л/4 rotation 5.3

32QAM 5.7

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"8PSK with 3Л/8 rotation" indicates that each symbol of the 8PSK is rotated in a radian of 3Л/8 before the pulse is formed. "16QAM with Л/4 rotation" indicates that each symbol of the 16QAM is rotated in a radian of Л/4 before the pulse is formed.

The following factors can cause the decrease in the power of signals modulated in the high order modulation scheme:

An increase in the power back-off of the power amplifier (PA) because the PAR of the high order modulation is high

A decrease in the output power of the PA because the requirements of the high order modulation for the EVM counters are higher

In view of the preceding factors, the EGPRS2 transceiver should use the power that is 2–6 dB less than the average power in the GMSK when sending the signals modulated in the 16QAM or 32QAM. POWERREDUCE16QAM and POWERREDUCE32QAM are set to specify the BTS output power decrease value in 16QAM or 32QAM. Table 3-2 lists the maximum output power decrease value in different modulation schemes.

Table 3-2 Maximum output power decrease value in different modulation schemes

EGPRS Level Modulation Scheme Output Power Decrease

EGPRS 8PSK 4 dB

EGPRS2-A 16QAM 6 dB

EGPRS2-A 32QAM 6 dB

In the case of Huawei double-transceiver series BTS and distributed BTS, set DIVERT16QAMDELAY and DIVERT32QAMDELAY to specify the delay of the diversity signal relative to the main signal in 16QAM and 32QAM so as to increase the RX signal gain of the MS.

3.1.2 EGPRS2-A Coding Schemes

In the downlink direction, eight coding schemes are introduced to EGPRS2-A: EGPRS2 downlink level A modulation and coding scheme-5 (DAS-5) to DAS-12. These coding schemes are used to transmit downlink RLC data blocks in the EGPRS2-A radio blocks. EGPRS2-A also has the coding schemes modulation and coding scheme-1 (MCS-1) to MCS-4 and MCS-6 to MCS-8 in the downlink direction. MCS-1 to MCS-4 are used to retain the complete structure of the coding scheme family. MCS-6 is used for the retransmission of the RLC data when EGPRS is changed to EGPRS-A. MCS-7 and MCS-8 are used for the multiplexing of the EGPRS MS and EGPRS2-A MS on the PDCH so that the EGPRS MS can decode the USF or PAN in the radio blocks of the downlink EGPRS2-A.

In the uplink direction, five coding schemes are introduced to EGPRS2-A: EGPRS2 uplink level a modulation and coding scheme-7 (UAS7)-UAS-11. These coding schemes are used to transmit uplink RLC data blocks in the EGPRS2-A radio blocks. EGPRS2-A also has the coding schemes MCS-1 to MCS-6 are in the uplink direction to retain the complete structure of the coding scheme family.

Table 3-3 and Table 3-4 show the relations among the coding scheme, modulation scheme, and data rate per PDCH of the downlink EGPRS2-A and uplink EGPRS2-A respectively.

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Table 3-3 Relations among the coding scheme, modulation scheme, and data rate per PDCH of the downlink EGPRS2-A

Coding Scheme

Code Rate Modulation Scheme

RLC Blocks per Radio Block

Raw Data Within one Radio Block (bits)

Family Data Rate per PDCH (kbit/s)

DAS-12 0.96 32QAM NSR

3 1968 Bp 98.4

DAS-11 0.80 3 1632 Ap 81.6

DAS-10 0.64 2 1312 Bp 65.6

DAS-9 0.68 16QAM NSR

2 1088 Ap 54.4

DAS-8 0.56 2 896 B 44.8

DAS-7 0.54 8-PSK 1 656 Bp 32.8

DAS-6 0.45 1 544 Ap 27.2

DAS-5 0.37 1 448 B 22.4

In the previous table, Code Rate refers to the coding rate when the piggy-backed ack/nack (PAN) field is not carried in radio blocks.

Table 3-4 Relations among the coding scheme, modulation scheme, and data rate per PDCH of the uplink EGPRS2-A

Coding Scheme

Code Rate Modulation Scheme

RLC Blocks per Radio Block

Raw Data Within One Radio Block (bits)

Family Data Rate per PDCH (kbit/s)

UAS-11 0.95 16QAM Normal Symbol Rate (NSR)

3 1536 Apad10 76.8

UAS-10 0.84 3 1344 B 67.2

UAS-9 0.71 2 1184 A 59.2

UAS-8 0.62 2 1024 Apad10 51.2

UAS-7 0.55 2 896 B 44.8

In the previous table, Code Rate refers to the coding rate when the PAN field is not carried in radio blocks.

3.2 Link Quality Control

3.2.1 Overview

The link quality control enables the system to dynamically adapt to the radio transmission environment by changing the modulation scheme and coding scheme during data transmission, thus improving the link quality and increasing the data throughput. EGPRS uses a set of high-efficient link quality control

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algorithms. The two link quality control modes are link adaptation (LA) and incremental redundancy (IR). For details, see GPRS/EGPRS Link Quality Control Feature Parameter Description.

The link quality control mechanism of EGPRS2 is nearly the same as that of EGPRS. The link quality control algorithm of EGPRS2, however, should be optimized on the basis of the link quality control algorithm of EGPRS because new modulation schemes and coding schemes are added to EGPRS2. Currently, only the link quality control algorithm of EGPRS2-A is supported, which includes the uplink EGPRS2-A coding scheme adjustment algorithm and downlink EGPRS2-A coding scheme adjustment algorithm.

3.2.2 Uplink EGPRS2-A Coding Scheme Adjustment Algorithm

The BSC adjusts the uplink EGPRS coding scheme according to the uplink bit error probability (BEP) measurement report sent by the BTS.BEP is the measured value of the EGPRS radio link quality. The link quality measurement is performed at the burst level.

The BEP measurement report is carried when the BTS sends uplink data frames or information frames over the Abis interface. The BEP measurement report contains mean of the bit error probability (MEAN_BEP) and coefficient of variation of the bit error probability (CV_BEP). MEAN_BEP is the mean of the calculated and filtered BEP values. CV_BEP is the measured value of the calculated and filtered coefficient variation of the BEP. For details, see 3GPP TS 45.008. Upon receiving the uplink data frame from the BTS, the BSC triggers the uplink EGPRS2-A coding scheme adjustment procedure if the BSC detects the change in the current link quality according to the measurement report. When the BTS cannot decode the uplink radio blocks correctly, it sends the BSC an uplink information frame that carries the BEP measurement report. After receiving the uplink information frame, the BSC triggers the uplink EGPRS2-A coding scheme adjustment procedure.

The principles of the uplink EGPRS2-A coding scheme adjustment algorithm are as follows:

1. The BSC determines whether to use the fixed EGPRS2-A coding scheme in the uplink based on the setting of UPE2AFIXMCS. If the fixed EGPRS2-A coding scheme is used, the uplink coding scheme is specified by UPE2AFIXMCS. Otherwise, the initial uplink coding scheme is specified by UPE2ADEFAULTMCS. Later, the BSC adjusts the uplink coding scheme according to the uplink BEP measurement report sent by the BTS.

2. If the non-fixed EGPRS2-A coding scheme is used in the uplink, the BSC filters the uplink BEP measurement report. Then, the uplink EGPRS2-A coding scheme is adjusted according to the filtered MEAN_BEP and CV_BEP. The algorithm is nearly the same as that in EGPRS. For details, see GPRS/EGPRS Link Quality Control Feature Parameter Description.

3. The modulation scheme may change during the EGPRS2-A coding scheme adjustment. To enhance the stability of coding scheme adjustment and to prevent ping-pong switchovers of modulation schemes, the leaky bucket algorithm is used when the low order scheme is switched to the high order scheme. The basic principles of the leaky bucket algorithm are as follows: Each time the coding scheme is switched from a low order scheme to a high order scheme between GMSK, 8PSK, and 16QAM, the bucket size increases; each time the coding scheme is adjusted within the low order schemes (relative to the schemes to which the low order scheme is switched), the bucket size decreases. The switching from a low order scheme to a high order scheme is allowed only when the bucket size reaches a specific value.

3.2.3 Downlink EGPRS2-A Coding Scheme Adjustment Algorithm

The MS periodically measures the downlink quality and filters the measured values to generate the link quality MR of the downlink EGPRS2. The filtering period for the downlink quality measurement is defined by the parameter BEPPERIOD. Then, the BSC broadcasts the system information (SI) that contains the BEP period to the MSs.

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The link quality MR of the downlink EGPRS2 is carried in the EGPRS PACKET DOWNLINK ACK/NACK TYPE2 message sent by the MS to the BSC. After receiving the EGPRS PACKET DOWNLINK ACK/NACK TYPE2 message, the BSC adjusts the downlink EGPRS2 coding scheme according to the BEP measurement report in the message. The principles of the downlink EGPRS2-A coding scheme adjustment algorithm are as follows:

1. The BSC determines whether to use the fixed EGPRS2-A coding scheme in the downlink based on the setting of DNE2AFIXMCS. If the fixed EGPRS2-A coding scheme is used, the downlink coding scheme is specified by DNE2AFIXMCS. Otherwise, the initial downlink coding scheme is specified by DNE2ADEFAULTMCS. Later, the BSC dynamically adjusts the downlink coding scheme according to the downlink BEP MR sent by the MS.

2. If the non-fixed EGPRS2-A coding scheme is used, the BSC obtains the MEAN_BEP and CV_BEP corresponding to the current modulation mode used by the downlink TBF from the EGPRS PACKET DOWNLINK ACK/NACK TYPE2 message. Then, the BSC adjusts the downlink EGPRS2-A coding scheme according to the MEAN_BEP and CV_BEP using the same algorithm as in the EGPRS. For details, see GPRS/EGPRS Link Quality Control Feature Parameter Description.

3.3 EGPRS Level Selection and Switching

When the MS initiates one phase access, the BSC cannot obtain the radio access capability of the MS, and thus does not know the capability of the MS for supporting EGPRS2 and EGPRS2-A. In this case, the EGPRS level is EGPRS by default. Later, if the BSC knows the capability of the MS for supporting EGPRS2-A, the BSC initiates the switching of EGRPS levels.

EGPRS Levels and Selection

EGPRS level consists of EGPRS and EGPRS2-A. Each EGPRS level has its own modulation mode set and coding scheme set, as shown in the following section:

EGPRS: coding scheme (MCS-1 to MCS-9); modulation mode (GMSK or 8PSK)

EGPRS2-A: uplink coding scheme (MCS-1 to MCS-6 or UAS-7 to UAS-11); uplink modulation mode (GMSK, 8PSK, or 16QAM NSR); downlink coding scheme (MCS-1 to MCS-4, MCS-6 to MCS-8, or DAS-5 to DAS-12); downlink modulation mode (GMSK, 8PSK, 16QAM NSR, or 32QAM NSR)

The BSC determines the EGPRS level of the TBF according to the radio access capability of the MS. The EGPRS level of the uplink TBF and that of the downlink TBF are independent of each other. The principles of selecting EGPRS levels are as follows:

If the MS supports EGPRS, the EGPRS level of the TBF is set to EGPRS.

If the MS supports EGPRS2-A in the uplink or downlink direction, the EGPRS level of the TBF in the corresponding direction is set to EGPRS or EGPRS2-A.

After determining the EGPRS level of the TBF, the BSC notifies the MS of the EGPRS level through the PACKET DOWNLINK ASSIGNMENT, PACKET UPLINK ASSIGNMENT, or PACKET TIMESLOT RECONFIGURE message. Then, the MS uses the specified EGPRS level for the corresponding TBF.

EGPRS Level Switching

1. EGPRS level switching of the uplink TBF

In the case of the uplink TBF, the BSC determines the EGPRS level to which the MS needs to switch. If EGPRS level switching is required, the BSC notifies the MS of the new EGPRS level through the PACKET TIMESLOT RECONFIGURE message or PACKET UPLINK ASSIGNMENT message.

2. EGPRS level switching of the downlink TBF

In the case of the downlink TBF, the BSC determines the EGPRS level to which the MS needs to switch. If EGPRS level switching is required, the BSC notifies the MS of the EGPRS level through the PACKET TIMESLOT RECONFIGURE message or PACKET DOWNLINK ASSIGNMENT message.

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3.4 Carrier Allocation Algorithm

The BSC allocates the EGPRS2-A carriers according to the baseband capability reported by the BTS. The application scenario of the cell is defined by the parameter CELLSCENARIO. The BTS optimizes the resource allocation according to the specific cell scenario to improve the overall processing capability.

The principles of the EGPRS2-A carrier allocation algorithm are as follows:

1. The BSC calculates the maximum number of EGPRS2-A carriers that the TRX group supports on the basis of the baseband processing capability of the TRX group (reported by the BTS). The baseband processing capability of the TRX group indicates the maximum amount of arithmetic operations required by the baseband algorithm of the multi-carrier module.

2. The BSC determines the uplink EGPRS2-A capability of the TRXs in the TRX group. The TRXs that meet the following conditions are selected to support the uplink EGPRS2-A:

− The parameter EGPRS2A determines whether the cell where the TRX is located supports EGPRS2-A.

− The number of TRXs selected to support the uplink EGPRS2-A is smaller than the maximum number of TRXs that can support the uplink EGPRS2-A.

− If all the preceding conditions are met, the TRXs are allocated by TRX ID in an ascending order to support the uplink EGPRS2-A.

3. The BTS determines the downlink EGPRS2-A capability of the TRXs in the TRX group. The TRXs that meet the following conditions are selected to support the downlink EGPRS2-A:

− The parameter EGPRS2A determines whether the cell where the TRX is located supports EGPRS2-A.

− The uplink EGPRS2-A capable TRXs are preferentially selected to support the downlink EGPRS2-A. In addition, the uplink EGPRS2-A capable TRXs are allocated by TRX ID in an ascending order to support the downlink EGPRS2-A.

3.5 Channel Allocation Algorithm

The BSC determines the allocation of TRXs for EGPRS2-A services according to the baseband capability reported by the BTS. If a TRX is allocated to support EGPRS2-A services, all the channels on the TRX can support EGPRS2-A. The BSC determines whether to allocate the EGPRS2-A channel based on the EGPRS2-A capabilities of the TRX and the MS.

The allocation of uplink EGPRS2-A channels must meet the following conditions:

1. The MS supports uplink EGPRS2-A.

2. The TRX carrying the channel supports uplink EGPRS2-A.

The allocation of downlink EGPRS2-A channels is based on the following conditions:

1. The MS supports downlink EGPRS2-A.

2. The TRX carrying the channel supports downlink EGPRS2-A.

If the EGPRS2-A capable MS is allocated a PDCH on the GPRS TRX or a PDCH on the EGPRS TRX and the allocated PDCH can't meet the MS Multislot Capability, dynamic TCH conversion is triggered on the EGPRS2-A TRX.

3.6 Multiplexing of GPRS, EGPRS, and EGPRS2 Capable MSs

Huawei EGPRS2-A supports the multiplexing of GPRS, EGPRS, and EGPRS2-A capable MSs on the same PDCH.

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When GPRS, EGPRS, and EGPRS2-A capable MSs are multiplexed on the same PDCH, the BSC determines the modulation mode and coding scheme of the current downlink radio block according to the radio access capability of the MS so that the MS can correctly decode the USF that is carried in the downlink radio block. Based on the radio support capability of the MS, the BSC restricts the downlink modulation and coding scheme of the radio block as follows:

When the MS specified by the USF supports only the GPRS and the EGPRS level of the downlink TBF is EGPRS, the modulation mode of the current radio block should be GMSK and the coding scheme can be CS-1 to CS-4 or MCS-1 to MCS-4.

When the MS specified by the USF supports only the GPRS and the EGPRS level of the downlink TBF is EGPRS2-A, the modulation mode of the current radio block should be GMSK and the coding scheme can be CS-1 to CS-4 or MCS-1 to MCS-4.

When the MS specified by the USF supports EGPRS and the EGPRS level of the downlink TBF is EGPRS2-A, the modulation mode of the current radio block can be GMSK or 8PSK and the coding scheme can be CS-1 to CS-4, MCS-1 to MCS-9, or DAS-5 to DAS-7.

For the purpose of synchronization, the BSC sends at least one downlink radio block in which the USF can be correctly decoded by the MS to each MS every 360 ms when scheduling downlink radio blocks. The modulation mode and the coding scheme of that radio block are determined according to the preceding rules.

When GPRS and EGPRS2-A capable MSs are multiplexed on the same PDCH, the modulation mode of downlink radio blocks on the PDCH must be GMSK if the uplink radio blocks of the GPRS MS need to be scheduled. In this case, the transmission rate of the downlink data of the EGPRS2-A MS decreases. When the parameter FORBIDEDGU is set to Open, GPRS MS and EGPRS2-A capable MSs can be multiplexed on the same PDCH. For EGPRS and EGPRS2-A capable MSs, they can be multiplexed on the same PDCH without any parameter setting.

3.7 Data Transmission

EGPRS2 RLC/MAC Radio Block Structure

Table 3-5 shows the structure of the EGPRS2 RLC/MAC radio block.

Table 3-5 EGPRS2 RLC/MAC radio block structure

RLC/MAC block

RLC/MAC header

RLC data block 1

RLC data block 2 (conditional)



PAN (optional)

An EGPRS2 RLC/MAC radio block consists of an RLC/MAC radio block header, one to four RLC data blocks, and a PAN domain (optional). The PAN domain is necessary only when the is supported. An EGPRS2-A RLC/MAC radio block contains one to three RLC data blocks according to the coding scheme.

Header type 4 and header type 5 are added for the uplink EGPRS2-A RLC/MAC radio block. Header type 4 is used for the UAS-7, UAS-8, and UAS-9 coding schemes; header type 5 is used for the UAS-10 and UAS-11 coding schemes.

Header type 4, header type 5, and header type 10 are added for the downlink EGPRS2-A RLC/MAC radio block. The existing Header type 2 is used for the DAS-5, DAS-6, and DAS-7 coding schemes; header type 4 is used for the DAS-8 and DAS-9 coding schemes; header type 10 is used for the DAS-10 coding scheme; header type 5 is used for the DAS-11 and DAS-12 coding schemes.

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3-8

EGPRS2-A RLC Data block Assembly and LLC PDU Segmentation

In the uplink direction, the BSC decodes each uplink EGPRS2-A RLC/MAC radio block into one to three RLC data blocks according to the coding scheme of the radio block. Then, the BSC extracts the RLC data unit from each RLC data block. When the BSN equals V(Q), the BSC assembles the collected RLC data units in the sequence of BSN to form the downlink LLC PDU, and then sends the LLC PDU to the SGSN over the Gb interface.

In the downlink direction, the BSC extracts LLC PDUs from the downlink LLC PDU queue and segments each LLC PDU to one to three EGPRS2-A RLC data units according to the determined coding scheme. Then, the BSC encodes the EGPRS2-A RLC data units into EGPRS2-A RLC data blocks. Finally, the BSC assembles the EGPRS2-A RLC data blocks into a complete EGPRS2-A RLC/MAC radio block and sends the radio block to the MS over the Um interface.

EGPRS2-A RLC Data Block Retransmission

The BSC controls the retransmission of downlink EGPRS2-A RLC data blocks. Before retransmitting an RLC data block, the BSC may change the coding scheme of the radio block to ensure that the coding scheme used for retransmission is in the same coding scheme set as the original coding scheme of that radio block. When the EGPRS level changes and the RLC data block needs to be retransmitted, the coding scheme may also need to be changed to ensure that the coding scheme used after EGPRS level changing is in the same coding scheme set as the original coding scheme of that radio block.

GSM BSS

EGPRS2 4 Parameters



4-1

4 Parameters

Table 4-1 Parameter description

Parameter ID NE MML Command Feature ID Feature Name

Description

BEPPERIOD BSC6900

SET GCELLEGPRSPARA(Optional)

GBFD-114201

EGPRS Meaning: Average period for sending the measurement report over the EGPRS channel

GUI Value Range: 0~10

Actual Value Range: 0~10

Default Value: 5

Unit: None

CELLSCENARIO BSC6900

SET GCELLBASICPARA(Optional)

GBFD-510803

GBFD-510804

Uplink EGPRS2-A

Downlink EGPRS2-A

Meaning: Information about the cell scenario. It needs to be sent to the BTS. Based on the information, the BTS optimizes the allocation of resources.

GUI Value Range: COMMON(COMMON), MULTIPATH(MULTIPATH), INDOOR(INDOOR), HIGHWAY(HIGHWAY)

Actual Value Range: COMMON, MULTIPATH, INDOOR, HIGHWAY

Default Value: COMMON

Unit: None

DIVERT16QAMDELAY

BSC6900


GBFD-510804

Downlink EGPRS2-A

Meaning: Delay of transmit diversity when 16QAM is used. Generally, the parameter is applicable to general fading environments. The transmit diversity can generally bring a gain of 3 dB to 5 dB. The fading conditions vary with the MS location; therefore, MSs in a

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GSM BSS

EGPRS2 4 Parameters



4-2


Description

fixed time delay obtain different gains. In addition, the EDGE service coding may be adversely affected. To avoid the preceding cases, the delay of transmit diversity must be configurable and can be set for GMSK and 16QAM respectively. Only the double-transceiver BTSs and the distributed BTSs can be configured with this parameter. For the BTSs of other types, this parameter is set to an invalid value 255.


Actual Value Range: 0.5~4

Default Value: 4

Unit: 0.125bit

DIVERT32QAMDELAY

BSC6900


GBFD-510804

Downlink EGPRS2-A

Meaning: Delay of transmit diversity when 32QAM is used. Generally, the parameter is applicable to general fading environments. The transmit diversity can generally bring a gain of 3 dB to 5 dB. The fading conditions vary with the MS location; therefore, MSs in a fixed time delay obtain different gains. In addition, the EDGE service coding may be adversely affected. To avoid the preceding cases, the delay of transmit diversity must be configurable and can be set for GMSK and 32QAM






GSM BSS

EGPRS2 4 Parameters



4-3


Description

respectively. Only the double-transceiver BTSs and the distributed BTSs can be configured with this parameter. For the BTSs of other types, this parameter is set to an invalid value 255.


Actual Value Range: 0.5~4

Default Value: 4

Unit: 0.125bit

DNE2ADEFAULTMCS

BSC6900


GBFD-510804

Downlink EGPRS2-A

Meaning: Default coding scheme used on the downlink EGPRS2-A link. If the downlink uses the dynamic coding scheme, this parameter specifies the coding scheme that is used for the transmission in initial access. If the downlink uses the fixed coding scheme, the TBF uses the fixed coding scheme.

GUI Value Range: MCS1(MCS1), MCS2(MCS2), MCS3(MCS3), MCS4(MCS4), MCS7(MCS7), MCS8(MCS8), DAS5(DAS5), DAS6(DAS6), DAS7(DAS7), DAS8(DAS8), DAS9(DAS9), DAS10(DAS10), DAS11(DAS11), DAS12(DAS12)

Actual Value Range: MCS1, MCS2, MCS3, MCS4, MCS7, MCS8, DAS5, DAS6, DAS7, DAS8, DAS9, DAS10,






GSM BSS

EGPRS2 4 Parameters



4-4


Description

DAS11, DAS12

Default Value: DAS6

Unit: None

DNE2AFIXMCS BSC6900


GBFD-510804

Downlink EGPRS2-A

Meaning: Fixed coding scheme that is used on the downlink EGPRS2-A link. If the downlink uses the fixed coding scheme, this parameter can be set MSC1-4, MSC7-8 or DAS5-12. If the downlink uses the dynamic coding scheme, this parameter is set to UNFIXED.

GUI Value Range: MCS1(MCS1), MCS2(MCS2), MCS3(MCS3), MCS4(MCS4), MCS7(MCS7), MCS8(MCS8), DAS5(DAS5), DAS6(DAS6), DAS7(DAS7), DAS8(DAS8), DAS9(DAS9), DAS10(DAS10), DAS11(DAS11), DAS12(DAS12), UNFIXED(UNFIXED)

Actual Value Range: MCS1, MCS2, MCS3, MCS4, MCS7, MCS8, DAS5, DAS6, DAS7, DAS8, DAS9, DAS10, DAS11, DAS12, UNFIXED

Default Value: UNFIXED

Unit: None

EGPRS2A BSC6900

SET GCELLGPRS(Optional)

GBFD-510803

GBFD-510804

Uplink EGPRS2-A

Downlink EGPRS2-A

Meaning: Whether the current cell supports EGPRS2-A

GUI Value Range: NO(No), YES(Yes)

Actual Value Range:






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GSM BSS

EGPRS2 4 Parameters



4-5


Description

NO, YES

Default Value: NO

Unit: None

FORBIDEDGU BSC6900

SET BSCPSSOFTPARA(Optional)

GBFD-113101

GBFD-114201

GBFD-119303

GBFD-119501

PDCH Dynamic Adjustment

EGPRS

Load Sharing

Adaptive Adjustment of Uplink and Downlink Channels

Meaning: Switch specifying whether to allow the downlink EGPRS TBF and the uplink GPRS TBF to share the same channel. Open: allow the downlink EGPRS TBF and the uplink GPRS TBF to share the same channel; Close: prohibit the downlink EGPRS TBF and the uplink GPRS TBF sharing the same channel.

GUI Value Range: OPEN(Open), CLOSE(Close)

Actual Value Range: OPEN, CLOSE

Default Value: OPEN

Unit: None

POWERREDUCE16QAM

BSC6900


GBFD-510804

Downlink EGPRS2-A

Meaning: Power attenuation level of timeslot 7 of the BCCH in 16QAM. The attenuation level ranges from 0 to 50, with the step of 0.2 dB. When the EDGE TRX sends signals in 16QAM, the transmit power must be lower than the mean power in GMSK.



Default Value: 0

Unit: 0.2dB

POWERREDUCE32 BSC69 SET GCELLBASICPARA(Optio

GBFD-5108 Downlink EGPRS2

Meaning: Power attenuation level of

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GSM BSS

EGPRS2 4 Parameters



4-6


Description

QAM 00 nal) 04 -A timeslot 7 of the BCCH in 32QAM. The attenuation level ranges from 0 to 50, with the step of 0.2 dB. When the EDGE TRX sends signals in 32QAM, the transmit power must be lower than the mean power in GMSK.



Default Value: 0

Unit: 0.2dB

UPE2ADEFAULTMCS

BSC6900


GBFD-510803

Uplink EGPRS2-A

Meaning: Default coding scheme used on the uplink EGPRS2-A link. If the uplink uses the dynamic coding scheme, this parameter specifies the coding scheme that is used for the transmission in initial access. If the uplink uses the fixed coding scheme, the TBF uses the fixed coding scheme.

GUI Value Range: MCS1(MCS1), MCS2(MCS2), MCS3(MCS3), MCS4(MCS4), MCS5(MCS5), MCS6(MCS6), UAS7(UAS7), UAS8(UAS8), UAS9(UAS9), UAS10(UAS10), UAS11(UAS11)

Actual Value Range: MCS1, MCS2, MCS3, MCS4, MCS5, MCS6, UAS7, UAS8, UAS9, UAS10, UAS11






GSM BSS

EGPRS2 4 Parameters



4-7


Description

Default Value: MCS6

Unit: None

UPE2AFIXMCS BSC6900


GBFD-510803

Uplink EGPRS2-A

Meaning: Fixed coding scheme that is used on the uplink EGPRS2-A link. If the uplink uses the fixed coding scheme, this parameter can be set to any one in MCS1-6 and UAS7-11. If the uplink uses the dynamic coding scheme, this parameter can be set to UNFIXED.

GUI Value Range: MCS1(MCS1), MCS2(MCS2), MCS3(MCS3), MCS4(MCS4), MCS5(MCS5), MCS6(MCS6), UAS7(UAS7), UAS8(UAS8), UAS9(UAS9), UAS10(UAS10), UAS11(UAS11), UNFIXED(UNFIXED)

Actual Value Range: MCS1, MCS2, MCS3, MCS4, MCS5, MCS6, UAS7, UAS8, UAS9, UAS10, UAS11, UNFIXED

Default Value: UNFIXED

Unit: None





GSM BSS

EGPRS2 5 Counters



5-1

5 Counters

Table 5-1 Counter description

Counter ID

Counter Name Counter Description

Feature ID Feature Name

1282411734

DOWN.EGPRS.DAS5.RLC.DATA.BLK L9341:Total Number of Downlink EGPRS DAS5 RLC Data Blocks

GBFD-510804

Downlink EGPRS2-A

1282411735


GBFD-510804

Downlink EGPRS2-A

1282411736


GBFD-510804

Downlink EGPRS2-A

1282411737


GBFD-510804

Downlink EGPRS2-A

1282411738


GBFD-510804

Downlink EGPRS2-A

1282411739


GBFD-510804

Downlink EGPRS2-A

1282411740


GBFD-510804

Downlink EGPRS2-A

1282411741


GBFD-510804

Downlink EGPRS2-A

1282411743

DOWN.EGPRS.DAS5.RLC.DATA.BLK.VALID.TOTAL

L9349:Total Number of Valid Downlink EGPRS DAS5 RLC Data Blocks

GBFD-510804

Downlink EGPRS2-A

1282411744



GBFD-510804

Downlink EGPRS2-A

12824117 DOWN.EGPRS.DAS7.RLC.DATA.BLK.VALID.T L9351:Total Number GBFD-5108 Downlink

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GSM BSS

EGPRS2 5 Counters



5-2

Counter ID



45 OTAL of Valid Downlink EGPRS DAS7 RLC Data Blocks

04 EGPRS2-A

1282411746



GBFD-510804

Downlink EGPRS2-A

1282411747



GBFD-510804

Downlink EGPRS2-A

1282411748



GBFD-510804

Downlink EGPRS2-A

1282411749



GBFD-510804

Downlink EGPRS2-A

1282411750



GBFD-510804

Downlink EGPRS2-A

1282411751

UP.EGPRS.UAS7.RLC.DATA.BLK L9365:Total Number of Uplink EGPRS UAS7 RLC Data Blocks

GBFD-510803

Uplink EGPRS2-A

1282411752


GBFD-510803

Uplink EGPRS2-A

1282411753


GBFD-510803

Uplink EGPRS2-A

1282411754


GBFD-510803

Uplink EGPRS2-A

1282411755


GBFD-510803

Uplink EGPRS2-A

12824117 UP.EGPRS.UAS7.RLC.DATA.BLK.VALID.TOTA L9370:Total Number GBFD-5108 Uplink






















GSM BSS

EGPRS2 5 Counters



5-3

Counter ID



56 L of Valid Uplink EGPRS UAS7 RLC Data Blocks

03 EGPRS2-A

1282411757

UP.EGPRS.UAS8.RLC.DATA.BLK.VALID.TOTAL

L9371:Total Number of Valid Uplink EGPRS UAS8 RLC Data Blocks

GBFD-510803

Uplink EGPRS2-A

1282411758



GBFD-510803

Uplink EGPRS2-A

1282411759



GBFD-510803

Uplink EGPRS2-A

1282411760



GBFD-510803

Uplink EGPRS2-A

1282411761

UPLINK.EGPRS2.A A9735:Processing Times of PS Services by MSs Supporting uplink EGPRS2-A

GBFD-510803

Uplink EGPRS2-A

1282411762

DOWNLINK.EGPRS2.A A9736:Processing Times of PS Services by MSs Supporting downlink EGPRS2-A

GBFD-510804

Downlink EGPRS2-A

1282423940

DOWN.EGPRS.DAS5.RLC.DATA.BLK.RESEND.RATE

RL9357:Retransmission Rate of Downlink EGPRS DAS5 RLC Data Blocks

GBFD-510804

Downlink EGPRS2-A

1282423941



GBFD-510804

Downlink EGPRS2-A

1282423942



GBFD-510804

Downlink EGPRS2-A

12824239 DOWN.EGPRS.DAS8.RLC.DATA.BLK.RESEN RL9360:Retransmis GBFD-5108 Downlink




















GSM BSS

EGPRS2 5 Counters



5-4

Counter ID



43 D.RATE sion Rate of Downlink EGPRS DAS8 RLC Data Blocks

04 EGPRS2-A

1282423944



GBFD-510804

Downlink EGPRS2-A

1282423945



GBFD-510804

Downlink EGPRS2-A

1282423946



GBFD-510804

Downlink EGPRS2-A

1282423947



GBFD-510804

Downlink EGPRS2-A

1282423948

UP.EGPRS.UAS7.RLC.DATA.BLK.RESEND.RATE

RL9375:Retransmission Rate of Uplink EGPRS UAS7 RLC Data Block

GBFD-510803

Uplink EGPRS2-A

1282423949



GBFD-510803

Uplink EGPRS2-A

1282423950



GBFD-510803

Uplink EGPRS2-A

1282423951



GBFD-510803

Uplink EGPRS2-A

1282423952



GBFD-510803

Uplink EGPRS2-A

12824313 UPLINK.EGPRS2.A.USERS S9350:Number of GBFD-5108 Uplink




















GSM BSS

EGPRS2 5 Counters



5-5

Counter ID



74 Uplink EGPRS2-A Users

03 EGPRS2-A

1282431375

DOWNLINK.EGPRS2.A.USERS S9351:Number of Downlink EGPRS2-A Users

GBFD-510804

Downlink EGPRS2-A

1282431378

PEAK.UPLINK.EGPRS2.A.USERS S9354:Maximum Number of Uplink EGPRS2-A Users

GBFD-510803

Uplink EGPRS2-A

1282431379

PEAK.DOWNLINK.EGPRS2.A.USERS S9355:Maximum Number of Downlink EGPRS2-A Users

GBFD-510804

Downlink EGPRS2-A

1282431382

TX.DOWN.EGPRS2.A.LLC.PDU.TOTAL.BYTE L9563:Total Bytes of Downlink LLC PDUs of EGPRS2-A Users

GBFD-510804

Downlink EGPRS2-A

1282431383

TX.DOWN.EGPRS2.A.LLC.PDU.THRPUT.RATE

L9564:Downlink Throughput of EGPRS2-A Users at the LLC Layer

GBFD-510804

Downlink EGPRS2-A

1282431384

TX.DOWN.EGPRS2.A.LLC.PDU.THRPUT.RATE.MAX

L9566:Maximum Downlink Data Rate of EGPRS2-A Users at the LLC Layer

GBFD-510804

Downlink EGPRS2-A

1282431385

TX.UP.EGPRS2.A.LLC.PDU.TOTAL.BYTE L9567:Total Bytes of Uplink LLC PDUs of EGPRS2-A Users

GBFD-510803

Uplink EGPRS2-A

1282431386

TX.UP.EGPRS2.A.LLC.PDU.THRPUT.RATE L9568:Uplink Throughput of EGPRS2-A Users at the LLC Layer

GBFD-510803

Uplink EGPRS2-A

1282431387

TX.UP.EGPRS2.A.LLC.PDU.THRPUT.RATE.MAX

L9570:Maximum Uplink Data Rate of EGPRS2-A Users at the LLC Layer

GBFD-510803

Uplink EGPRS2-A

1282449231

AVG.UPLINK.EGPRS2.A.USERS AS9358:Average Number of Uplink EGPRS2-A Users

GBFD-510803

Uplink EGPRS2-A

1282449232

AVG.DOWNLINK.EGPRS2.A.USERS AS9359:Average Number of Downlink EGPRS2-A Users

GBFD-510804

Downlink EGPRS2-A

1282449235

TX.DOWN.EGPRS2.A.LLC.PDU.THRPUT.RATE.AVG

AL9565:Downlink Data Rate of EGPRS2-A Users at the LLC Layer

GBFD-510804

Downlink EGPRS2-A

























GSM BSS

EGPRS2 5 Counters



5-6

Counter ID



1282449236

TX.UP.EGPRS2.A.LLC.PDU.THRPUT.RATE.AVG

AL9569:Uplink Data Rate of EGPRS2-A Users at the LLC Layer

GBFD-510803

Uplink EGPRS2-A



GSM BSS

EGPRS2 6 Glossary



6-1

6 Glossary

For the acronyms, abbreviations, terms, and definitions, see the Glossary.

Glossary.htm

GSM BSS

EGPRS2 7 Reference Documents



7-1

7 Reference Documents

[1]. 3GPP TS 44.060: "Radio Link Control/Medium Access Control (RLC/MAC) protocol"

[2]. 3GPP TS 43.064: "Overall description of the GPRS radio interface; Stage 2"

[3]. 3GPP TR 45.912: "Feasibility study for evolved GSM/EDGE Radio Access Network (GERAN)"

[4]. 3GPP TS 23.060: "General Packet Radio Service (GPRS); Service Description; Stage 2"

[5]. 3GPP TS 45.008: "Radio subsystem link control"

[6]. 3GPP TS 45.005: "Radio transmission and reception"

[7]. 3GPP TS 45.004: “Modulation”

[8]. 3GPP TS 25.213: "Spreading and modulation (FDD)"

[9]. 3GPP TS 25.223: "Spreading and modulation (TDD)"

[10]. BSC6900 Feature List

[11]. BSC6900 Optional Feature Description

[12]. BSC6900 GSM Parameter Reference

[13]. BSC6900 GSM MML Command Reference

[14]. BSC6900 GSM Performance Counter Reference

[15]. GPRSEGPRS Link Quality Control Feature Parameter DescriptionGPRSEGPRS Link Quality Control.htm



EGPRS

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Transcript of EGPRS