Coverage Extension and savings in cellular infrastructure

A solution with the VEGA antenna in Miramar – Cordoba, Argentina

BTS Miramar-CO043 CDMA 850MHz

BTS to targetarea – 4 Kms.

Challenge:Low coverage in Miramar (Cordoba)Argentina, that does not guarantee indoor service

There is no leading signal. There exist3 – 4 dominant signals.

The nearest BTS is CO 043 located about 4 Kms. from Miramar.The former sector (CO 043 – 1) antenna aimed at the Community has the following configuration;

Antenna DB858DG65ESXAzimuth 65° tilt 1° height aprox. 90 m.

*Adding more BTS

(2 – 3 sectors) $$$$

*Tower Top Amplifiers, Repeaters $$$

*Implementation of special features, antenna hoping, intelligent downlink

diversity $$

*Use of VEGA very high gain narrow

beam dual polarization antennas $

Possible alternatives to improve coverage

Changing Antennas from DB858DG65ESX

To VEGA CC-12

Frequency (MHz) 805 – 960Polarization +45° -45°Gain 22.5 dBiBeam width (h & v) 11.5Front – back ratio >28 dBDown tilt 0° - 15°

Advantages – The VEGA antenna has more than 5 dB gain and more than three times the power of the existing panel antenna.

Risk – The narrow horizontal beam of the VEGA may not support full lateral coverage

The Best Solution – Two panel antennas DB858DG65ESX with two VEGA CC-12 antennas

Two co-directional antennas are used to save on power combiner losses due to large number of carriers required at this area

THE VEGA Antenna Solution

Plots of Best Server by Sector

Major Servers by rankFrec. 242: 48.7% of samplesFrec. 219: 35.2% of samplesFrec. 218: 6.03% of samples

Major Servers by rankFrec. 242: 94.15% of samplesFrec. 241: 3.38% of samples

Frec. 224: 1.85% of samples

Before adding VEGA antenna After adding VEGA antenna

AfterBefore

Best Server by Force of Signal level at all SitesLevels were lower than -93 dBm which couldnot guarantee indoorcoverage

Improvement in levels of over15 dBm. New levels guaranteegood indoor service

After Before

% de Muestras de Propagación Frec. 242Rangos de Nivel de Señal en dBm

0.00%

10.00%

20.00%

30.00%

40.00%

50.00%

60.00%

70.00%

>71

71-8

3

83-9

3

93-1

04

Rangos

Después Antes

Propagation plots channel 242

The VEGA antenna has created a notable improvement as observed in coverage distribution

Percentage of samples of frequency 242ranked in dBm

After Before

Level

Conclusions & Recommendations

*The VEGA antenna notably improved coverage and insured indoor service to Sector 1 of BTS CO043.

*It should be verified that the increase in traffic does not exceed the present capacity of this sectors radios.

*If this happens it would be recommendable to strengthen the signal of nearby sectors to help balance the traffic within the area.

*This new sector should have enough overlay with the current sector in order to use features such as directed retry. This feature will contribute to balance the traffic load

Thank You For Your Attention