ZXG10 BS30: Compact Outdoor GSM BTS

ZXG10 BS30 is a part of ZTE’s Base Station Subsystem (BSS). Its main job is to fulfill the functions related to wireless connection. One of its ends links to the Mobile Station (MS) through the Um interface, and the other to the Base Station Controller (BSC) through the Abis interface. ZXG10 BS30 is compatible with the Phase II+ standard completely. It can be configured flexibly according to users’ demands, and support star, chain, tree, and other network modes of PCM link.

Product Consultant: Cheng Yang
Email address: cheng.yang@zte.com.cn

ZXG10 BS30 is a third generation compact outdoor GSM Base Transceiver Station (BTS) product developed by ZTE Corporation, a leading telecom equipment manufacturer. It supports 40 W output per frequency carrier and build-in transmission equipment. It can not only achieve wide coverage, but also bear inclement working environment and run under various climatic conditions. It supports 220 V AC and its installation and maintenance are very convenient, which helps save much of the investment in equipment rooms, iron towers, and power supplies and implement rapid BTS installation and operation.

1 ZXG10 BS30 Features
ZXG10 BS30 has some excellent system features, such as superpower environmental adaptation, great output power for wide coverage, mature and reliable frequency carrier module, flexible power adaptability, flexible transmission solution, small volume, light weight, rapid and reliable software online update, quick start-up and exterior relay alarm.
With superpower environmental adaptation, ZXG10 BS30 can normally run under the condition of temperature from -40 ℃ to 55 ℃ and relative humidity from 5% to 98%. It adopts the heat pipe refrigeration technology, used in the aerospace industry in the past, to ensure the stable and reliable operation of the high-power device. Its build-in auto-heating module greatly improves its adaptability to low-temperature conditions. Two-layer folded metal boards are welded into the cabinet that has high mechanical strength. The labyrinth waterproof sealing structure is combined with sealing strips, which achieves IP55 level of Enclosure Protection.

    ZXG10 BS30’s output power reaches up to 40 W. Avoiding combiner’s insertion loss and using the feed-cable free installation method, it has a terrifically greater coverage than the micro BTS, and even wider than ordinary macro BTS. Besides, its output power can be adjusted agilely between 2 W-40 W, so it can cover small hotspots and blind-spot areas, as well as large areas. In a word, it has the strengths of both the macro and micro BTSs.

    With high quality industrial-grade elements, mature module designing and redundant backup of the important function module, the BTS works stably and reliably.

    Besides supporting -48 V DC power supply, ZXG10 BS30 can integrate primary power sources, and support
220 V AC with an adjustable voltage range of 130 V-300 V. It also supports the secondary power down function of the power module, so the transmission equipment can be kept power on when it meets a power-dump emergency, which implements its unceasing running under the condition of cascading.

    ZXG10 BS30 has selectable build-in transmission equipment. With uplink and downlink E1 interfaces, the equipment can provide transmission support for other equipment.

    With a small volume and light weight, the BTS is designed for convenient transportation, installation and maintenance. It can move agilely, and be installed indoors and outdoors.

    With the Flash Memory technology, ZXG10 BS30’s software can keep two versions at the same time. Services in use won’t be broken when it downloads software. The original version will be reactivated rapidly if the software update fails, which brings the BTS with high reliability. Software update is agile, and both OMC-R remote update and LMT local update are available.

    When the system starts up, only configuration data need downloading while its software is kept in the Flash Memory. With an interior high-speed bus, the BTS’s start-up needs only 1 minute. After power cuts and recovery, the BTS can reboot quickly and return to work automatically without manual intervention. In addition, it is very convenient for commissioning debug and routine maintenance.

    ZXG10 BS30 has an excellent exterior relay alarm function including alarm pick-up and report. The function helps gather other equipment’s alarms other than the BTS’s. For example, the air conditioning unit provides a relay alarm called air conditioning power-down, and links this alarm port to ZXG10 BS30’s input port. Then this alarm can be observed at OMC-R of the BTS. Cooperated with other exterior equipment or environment monitoring units, it can provide ideal environment monitoring schemes.

2 Functionalities and System Parameters
ZXG10 BS30 is a part of ZTE’s Base Station Subsystem (BSS). Its main job is to fulfill the functions related to wireless connection. One of its ends links to the Mobile Station (MS) through the Um interface, and the other to the Base Station Controller (BSC) through the Abis interface. ZXG10 BS30 is compatible with the Phase II+ standard completely. It can be configured flexibly according to users’ demands, and support star, chain, tree, and other network modes of PCM link.

2.1 Functionalities
    (1) It is in accordance with the standard of GSM Phase II+, and also compatible with Phase I and Phase II.
    (2) It supports GSM900/1800/1900 and EGSM900.
    (3) It offers such service channels as TCH/FS, TCH/EFS, TCH/HS, TCH/F9.6 TCH/F4.8, TCH/F2.4, GPRS CS1-CS4 service channel and EDGE MCS1-MCS9 service channel.
    (4) Diversified reception is supported.
    (5) The software radio technology is adopted to improve channel decoding performance, system receiving sensitivity and anti-jamming capability.
    (6) Frequency hopping is supported. The anti-fading capability is improved.
    (7) Discontinuous Transmit (DTX) is supported, and the total interfering level of interfering radio signals is decreased.
    (8) The BTS supports one frequency carrier per cabinet and maximal S222 station type by BTS cascading.
    (9) It supports E1 cascading output and the star, chain and tree configuration of the Abis interface.
    (10) LapD signaling multiplexing of the Abis interface is supported.
    (11) Its Abis interface link has the auto-bridge-protection function under the condition of BTS power down when several BTSs cascade.
    (12) BTS uplink and downlink power control is supported.
    (13) A5/2 encryption is supported.
    (14) E1, Synchronous Digital Hierarchy (SDH) optical transmission, microwave,  satellite and other transmission modes are supported.
    (15) External lightening protection equipment is supported, and the lightening shield of the AC power supply is offered.
    (16) External UPS used as a slave power supply is allowed.
    (17) ZXG10 BS30 supports
over-voltage and under-voltage alarms of the power supply as well as the entrance control relay alarm.
    (18) The BTS offers the external relay alarm.
    (19) With the Local Management Terminal (LMT), it examines the local site status of configuration and alarm.

2.2 Performance Parameters
    (1) At the Um interface, the output power is 40 W, BTS power control is the 6-level static (2 dB per level) and 15-level dynamic (2 dB per level, and the antenna Voltage Standing Wave Ratio (VSWR) is less than 1.5.

    (2) At the Abis interface, the physical layer electric parameter meets the requirements of ITU-T G.703 and ITU-T G.704. The interface supports 3 pairs of E1 input-output.

    (3) The BTS cabinet has a height of 580 mm, width of 400 mm and thickness of 284 mm. And the whole device weights about 39 kg.

    (4) The working environment of the BTS is -40 ℃-55 ℃ in temperature and 5%-98% in relative humidity. The maximum wind speed of 150 km/h is endured. The leak-proof level is IP55. Its storage asks for a temperature of -45 ℃-70 ℃ and relative humidity of 5%-98%. The temperature variation rate should be less than 1 ℃/min.

    (5) Each cabinet has 1 frequency carrier at the most, while each station has a maximum of 6 frequency carriers. The maximal station type is S222, and maximal site cascading is 4.

    (6) As for power supply, the input voltage is AC 220 V per 50 Hz with a single-phase three-wire power supply. The allowable voltage variation range is 130 V-300 V, while the frequency is allowed to vary between 45 Hz-65 Hz. Besides, DC of -48 V (adjustable in -57 V--40 V DC) also works well.

    (7) The ground resistance of the cabinet shell is less than 5 Ω.

    (8) The power dissipation is 260 W.

    (9) The Electromagnetic Compatibility (EMC) meets the specifications of ETSI EN 301 489-1, ETSI EN 301 489-8 and YD/T 1139-2001.

3 Typical Solutions of  ZXG10 BS30
ZXG10 BS30 can support wide coverage and great traffic at the same time, so it is very suitable for being deployed at transportation lines, hotspot areas, villages, small towns and resorts.

    If a traffic line is straight and the surrounding topography is relatively flat, directional station can be adopted (such as S11). An antenna with narrow lobe and high gain (such as 21 dBi/40°) will meet the requirement of taeniate coverage. In this way, a wide coverage in flat topography may be implemented.

    However, when a transportation line is relatively curved and its surrounding topography is complicated, in view of obstruction shading and other factors, it is suggested to choose the solution of ZXG10 BS30 plus "8" antenna (such as 14 dBi/65°) to meet the requirement of cell bilateral coverage.

    In a curved area along a transportation line, if the bending is relatively big and there is great obstruction there, like massifs, it is suggested to use the solution of S11 plus directional antenna. The antenna is placed at the curved point, and two cell directions can be set flexibly according to the road curvature.If there are villages or small towns nearby the curve, the solution of S111 plus directional antenna can be used, and its sector direction can be set flexibly.
 In the area with many curved roads, it is suggested to adopt ZXG10 BS30 to realize the straight way coverage and repeaters or micro stations to fill up the blind spots.

    In a common area where the coverage includes the surrounding countryside or shipside, the solution of ZXG10 BS30 plus omni-directional antenna (11 dBi/360°) can be chosen. But if the coverage only includes unilateral villages, the solution of ZXG10 BS30 plus great lobe angle antenna(13 dBi/210°) will be better.

    However, the coverage for resorts is very different from that for transportation lines. When the development potential of a resort is taken into consideration, macro BTS has the priority to be used for the resort coverage if conditions permit. In case that the conditions are not suitable for building a macro BTS, ZTE’s shelter BTS can be used, which integrates transmission, power supply and monitoring equipment, and can support large voice traffic. For partial hot spots with heavy traffic, ZXG10 BS30 can be used to implement additional coverage. In order to avoid breaking the natural scenery, some solutions such as cheating color antenna can be used. Macro BTS penetration coverage solution is suggested for small beauty spots, such as pavilions, terraces, towers, and etc, while the solution of ZXG10 BS30 plus directional antenna for large ones.

4 Summary
With significant advantages, ZXG10 BS30 has won wide recognition at home and abroad since it was launched. It has got a large-scale application, and more than 5 000 frequency carriers have been used in existing networks. Its application is growing rapidly. ZTE Corporation is dedicated to provide high quality products and services for clients.

Manuscript received: 2004-09-17