antenna hopping trial

Company Confidential

1 © 2005 Nokia V1-Filename.ppt / yyyy-mm-dd / Initials

Bharti : Antenna Hopping Trial

Trial conducted in First week of March’07


2 © 2005 Nokia V1-Filename.ppt / yyyy-mm-dd / Nihar Nanda

Introduction to Antenna Hopping

• Antenna Hopping for UltraSite BTS• The optional Antenna Hopping for UltraSite BTS is targeted at optimizing capacity and performance.• Antenna hopping is an enhancement to Radio Frequency (RF) hopping. The Antenna Hopping for UltraSite BTS enables the TRXs in an RF

hopping BTS to transmit with all the TX antennas in the BTS. Antenna Hopping uses the existing baseband (BB) hopping functionality in the BTS.

• Furthermore, with Antenna Hopping for UltraSite BTS it is possible to achieve space diversity to the regular RF hopping configuration, which means that there is a distance that separates two or more transmitting antennas providing uncorrelated signals. At the mobile unit, a separation of half a wavelength is the minimum for obtaining uncorrelated signals. At the base station frequency, the antenna height and antenna spacing make the correlation efficient.

• The Antenna Hopping for UltraSite BTS can be used with or without RF Hopping. • Benefits of Antenna Hopping for UltraSite BTS• With Antenna Hopping for UltraSite BTS the user can have a 2 dB gain in a narrowband environment (3.6 MHz) without an extra TRX as required

by Intelligent Downlink Diversity (IDD). • With Antenna Hopping it is possible to gain better spectral efficiency on the BCCH layer. The Antenna Hopping also helps to avoid the

interference and frequency selective fading. By tighter BCCH reuse more frequencies can be used in the hopping traffic layer, thus providing better capacity for narrowband networks.

• Restrictions to Antenna Hopping for UltraSite BTS• The following functionalities cannot be used simultaneously with Antenna Hopping:• Baseband Hopping (BB) or DFCA Hopping in the same BTS• Intelligent Downlink Diversity (IDD) in the same BTS-cabinet• Remote Tune Combiner (RTC) in the same BTS• Antenna Hopping for UltraSite BTS is OFF in the BTS • when TRX(s) are down• if the number of working TRXs decreases below 2 TRXs /BTS• Requirements for Antenna Hopping for UltraSite BTS• Antenna Hopping is supported only by:• UltraSite EDGE HW• EDGE TRXs• Non-EDGE TRXs can be used in the same cabinet if it is in a non-hopping or RF hopping mode.• Antenna hopping groups can include the BCCH.• The minimum configuration for the Antenna Hopping is 2 TRXs/cell where both TRXs are used for antenna hopping.

Antenna Hopping Guideline



ANTENNA HOPPING FEATURE TRIAL

ORISSA



Some Highlights of the Feature

1. CX4 software version should be present in the BTS.

2. With Antenna Hopping it is possible to gain better spectral efficiency on the BCCH layer.

3. The Antenna Hopping also helps to avoid the interference and frequency selective fading.

4. Major Improvement on SDCCH Drop & TCH Assgn Succ Rate expected.

5. No hardware changes required in BTS for implementing the feature.



Activating Antenna Hopping for UltraSite BTS

• Lock the BTS so that the Antenna Hopping for UltraSite BTS parameter can be modified (EQS).

ZEQS:BTS=1:L;

• Activate the Antenna Hopping in the BCS (WOA).

ZWOA:2,809,A;

• Activate the Antenna Hopping in the BTS (EQE).

ZEQE:BTS=1:AHOP=Y;

• Unlock the BTS (EQS).

ZEQS:BTS=1:U;

Note: It was observed that some TRXs goes into blocked state after sector unlocking. After resetting the individual TRXs, it will come up.



Feature enabled on 2nd Mar in all sites of BSC37KNP. Hourly basis Comparison of SDCCH Drop rate is given below.

TIME BSC INT IDSD DROP ( 1st

Mar07)SD DROP ( 3rd

Mar07)01/03/2007 00 BSC37KNP 526780 1.87 0.9701/03/2007 01 BSC37KNP 526780 1.82 0.7401/03/2007 02 BSC37KNP 526780 1.44 0.8301/03/2007 03 BSC37KNP 526780 1.93 0.8601/03/2007 04 BSC37KNP 526780 1.53 0.7701/03/2007 05 BSC37KNP 526780 1.51 0.7201/03/2007 06 BSC37KNP 526780 1.73 0.7501/03/2007 07 BSC37KNP 526780 2.17 0.8701/03/2007 08 BSC37KNP 526780 2.20 0.9701/03/2007 09 BSC37KNP 526780 1.80 0.8901/03/2007 10 BSC37KNP 526780 1.96 0.8201/03/2007 11 BSC37KNP 526780 1.94 0.8701/03/2007 12 BSC37KNP 526780 1.88 0.7801/03/2007 13 BSC37KNP 526780 1.82 0.7401/03/2007 14 BSC37KNP 526780 1.63 0.8101/03/2007 15 BSC37KNP 526780 1.61 0.8001/03/2007 16 BSC37KNP 526780 1.65 0.8701/03/2007 17 BSC37KNP 526780 1.87 0.9901/03/2007 18 BSC37KNP 526780 2.14 1.1401/03/2007 19 BSC37KNP 526780 2.56 1.0401/03/2007 20 BSC37KNP 526780 2.72 1.1101/03/2007 21 BSC37KNP 526780 2.80 1.1801/03/2007 22 BSC37KNP 526780 2.57 0.9001/03/2007 23 BSC37KNP 526780 1.79 0.66



Feature enabled on 2nd Mar in all sites of BSC37KNP. Hourly basis Comparison of TCH Assgn Succ Rate is given below.

TIME BSC INT IDTASR

( 1st Mar07)TASR

( 3rd Mar07)

01/03/2007 00 BSC37KNP 526780 96.44 97.4001/03/2007 01 BSC37KNP 526780 96.29 97.7201/03/2007 02 BSC37KNP 526780 96.62 98.4401/03/2007 03 BSC37KNP 526780 97.64 98.5701/03/2007 04 BSC37KNP 526780 95.73 97.8201/03/2007 05 BSC37KNP 526780 96.21 98.0501/03/2007 06 BSC37KNP 526780 96.71 97.7301/03/2007 07 BSC37KNP 526780 96.86 98.0001/03/2007 08 BSC37KNP 526780 97.19 98.2401/03/2007 09 BSC37KNP 526780 97.57 98.4901/03/2007 10 BSC37KNP 526780 97.35 98.5601/03/2007 11 BSC37KNP 526780 97.44 98.4401/03/2007 12 BSC37KNP 526780 97.48 98.3901/03/2007 13 BSC37KNP 526780 97.34 98.1701/03/2007 14 BSC37KNP 526780 97.31 97.9601/03/2007 15 BSC37KNP 526780 97.31 98.0301/03/2007 16 BSC37KNP 526780 97.71 98.0401/03/2007 17 BSC37KNP 526780 97.62 98.4701/03/2007 18 BSC37KNP 526780 97.32 98.1501/03/2007 19 BSC37KNP 526780 96.99 98.0701/03/2007 20 BSC37KNP 526780 96.66 98.1201/03/2007 21 BSC37KNP 526780 96.55 98.3001/03/2007 22 BSC37KNP 526780 96.52 97.8501/03/2007 23 BSC37KNP 526780 96.98 98.00




Gujarat



Gujarat : BSC level SDCCH & TCH Drop KPI

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.80

3/5

/2007

3/6

/2007

3/7

/2007

3/8

/2007

3/9

/2007

3/1

0/2

007

3/1

1/2

007

3/1

2/2

007

3/1

3/2

007

3/1

4/2

007

Date

% D

rop

Sd Drop-BSC25CHn TCH Drop- BSc25CHn

AHOP Implemented in BSC25CHN



Gujarat : BSC level HOSR & TASR KPI

94

95

96

97

98

99

100

3/5

/2007

3/6

/2007

3/7

/2007

3/8

/2007

3/9

/2007

3/1

0/2

007

3/1

1/2

007

3/1

2/2

007

3/1

3/2

007

3/1

4/2

007

Date

% S

uccess R

ate

TASR-BSC25CHn HOSR-BSC25CHN

AHOP implemented in BSC25CHN



Gujarat : Results

SDCCH Drop Rate improved from 1.52% to 1.22% i.e. 20.1% improvement.

TCH drop Rate improved from 1.06% to 0.88% i.e. 17.1% improvement.

TCH Assignment Success Rate improved from 98% to 98.3% i.e. 14.72% improvement.

HO Success Rate improved from 95.45% to 96.23% i.e. 17.51% improvement.



WB : BSC level SDCCH & TCH Drop KPI

0

0.5

1

1.5

2

2.5

32-

Mar

-07

3-M

ar-0

7

4-M

ar-0

7

5-M

ar-0

7

6-M

ar-0

7

7-M

ar-0

7

8-M

ar-0

7

9-M

ar-0

7

10-M

ar-0

7

11-M

ar-0

7

% D

rop

SDCCH Drop TCH Drop

AHOP implemented in BSC33MTR



WB : BSC level HOSR & TASR KPI

78

80

82

84

86

88

90

92

94

96

98

100

2-M

ar-0

7

3-M

ar-0

7

4-M

ar-0

7

5-M

ar-0

7

6-M

ar-0

7

7-M

ar-0

7

8-M

ar-0

7

9-M

ar-0

7

10-M

ar-0

7

11-M

ar-0

7

% S

ucc

ess

Rat

e

TCH Assignment HOSR

AHOP implemented in BSC33MTR




West Bengal



WB : Results

SDCCH Drop Rate improved from 2.02% to 1.08% i.e. 46.33% improvement.

TCH drop Rate improved from 2.45% to 1.92% i.e. 21.27% improvement.

TCH Assignment Success Rate improved from 96.46% to 97.58% i.e. 31.7% improvement.

HO Success Rate improved from 85.94% to 89.24% i.e. 23.47% improvement.



Conclusion

• Antenna Hopping gave drastic improvement on cell-wise and NBH TCH Drop, SDCCH Drops, TASR, HOSR and RxQualDL.

• Downlink diversity provided by AH helps minimize the impact of fast fading on non-hopping TRXs and stationary users. With the feature we can gain roughly about 20% drop call performance. Cluster level testing indicates that there is an over all improvement with mobile traffic and stationary traffic – albeit the impact is much more significant on the stationary traffic. The gains on the BCCH are reflected with the improved HO success rate and Drop Call rate. HO related drops have been reduced because of better BSIC decoding.

• Spectrum limited areas would benefit with AH as shown on the performance trends with 12 BCCH reuse. The benefits would also extend to the non-hopping layer if the available frequencies in the MA list have high correlation.



THANK YOU

antenna hopping trial

Documents

hourly basis

ppt yyyy

frequency

tch drop kpi

sd drop

antenna hopping

tasr kpi

bcch layer