|यो एउटा अनाथ (एक्लो) पृष्ठको रुपमा छ, यो पृष्ठ कुनै पनि पृष्ठसित नजोडिएको अथवा एक-दुइवटा वटासित मात्र जोडिएको हुन सक्छ। कृपया सम्बन्धित लेखबाट; यस पृष्ठसित लिङ्क जोड़्न सहायता गर्नुहोस् सुझाव यहाँ उपलब्ध हुनसक्छ। (जुन २०११)|
एक base(वेस) transceiver(ट्रान्सिभर) station(स्टेशन) (BTS) अथवा cell(सेल) site एक उपकरणीय एकाइ हो जासले (युजर इक्विपमेन्ट(हामीले बोक्ने मोबाइल सेट)) जस्तै मोबाइल फोनहरू, डब्लुएलएल फोनहरू, वेतार इन्टरनेट जडान भएका कम्प्युटरहरू ,वाइफाइ तथा वाइम्याक्स जस्ता वेतार सञ्चार प्रणालीमा सेवा प्रदानगर्ने कार्य गर्दछ । कुनै जिएसएम, सिडिएमए, डब्लोएलएल, वान, वाइफाइ, वाइम्याक्स प्रणालीको वेतार सञ्चार प्रविधि प्रयोग गर्न सकिन्छ र प्रयोग भएका हुनसक्छन् । बिटिएस (BTS) लाई रेडियो बेस स्टेशन (RBS), नोड B ( थ्रिजि सञ्जालमा) वा साधारण रूपमा , बेस स्टेशन (BS) भनेर पनि बुझिन्छ ।
मोबाइल सञ्चारमा BTS [सम्पादन गर्ने]
एक GSM सञ्जाल निम्न उपप्रणालीले बनेको हुन्छ :
- सञ्जाल तथा स्विचिङ्ग उपणाली Network and Switching Subsystem (NSS) -एक MSC र संवद्द रेजिस्टरहरू ।
- बेस स्टेशन उपप्रणाली Base Station subsystem (BSS) – एक BSC तथा केहीl BTSहरू
- सञ्चाल सहायता प्राणाली Operations support system (OSS) - सञ्जाल सम्भारको लागि ।
Though the term BTS can be applicable to any of the wireless communication standards, it is generally and commonly associated with mobile communication technologies like GSM and CDMA. In this regard, a BTS forms part of the base station subsystem (BSS) developments for system management. It may also have equipment for encrypting and decrypting communications, spectrum filtering tools (band pass filters) etc. antennas may also be considered as components of BTS in general sense as they facilitate the functioning of BTS. Typically a BTS will have several transceivers (TRXs) which allow it to serve several different frequencies and different sectors of the cell (in the case of sectorised base stations). A BTS is controlled by a parent base station controller via the base station control function (BCF). The BCF is implemented as a discrete unit or even incorporated in a TRX in compact base stations. The BCF provides an operations and maintenance (O&M) connection to the network management system (NMS), and manages operational states of each TRX, as well as software handling and alarm collection. The basic structure and functions of the BTS remains the same regardless of the wireless technologies.
General Architecture [सम्पादन गर्ने]
A BTS in general has the following units:
- Transceiver (TRX)
- Quite widely referred to as the driver receiver (DRX). Basically does transmission and reception of signals. Also does sending and reception of signals to/from higher network entities (like the base station controller in mobile telephony)
- Power amplifier (PA)
- Amplifies the signal from DRX for transmission through antenna; may be integrated with DRX.
- Combines feeds from several DRXs so that they could be sent out through a single antenna. Allows for a reduction in the number of antenna used.
- For separating sending and receiving signals to/from antenna. Does sending and receiving signals through the same antenna ports (cables to antenna).
- This is also considered a part of the BTS.
- Alarm extension system
- Collects working status alarms of various units in the BTS and extends them to operations and maintenance (O&M) monitoring stations.
- Control function
- Control and manages the various units of BTS including any software. On-the-spot configurations, status changes, software upgrades, etc. are done through the control function.
- Baseband receiver unit (BBxx)
- Frequency hopping, signal DSP, etc.
Important terms regarding a mobile BTS [सम्पादन गर्ने]
- Diversity techniques
- To improve the quality of the received signal, often two receiving antennas are used, placed at an equal distance to an uneven multiple of a quarter of wavelength (for 900 MHz the wavelength it is 30 cm). This technique, known as antenna diversity or space diversity, avoids interruption caused by path fading. The antennas can be spaced horizontally or vertically. Horizontal spacing requires more complex installation, but better performance is obtained in this configuration.
- Other than antenna or space diversity, there are other diversity techniques such as frequency/time diversity, antenna pattern diversity, and polarization diversity.
- The process of creating more coverage and capacity in a wireless system by having more than one cell site cover a particular amount of geography. Each cell site covers a smaller area, with lower power MHz and thus offers the ability to reuse frequencies more times in a larger geographic coverage area, such as a city or MTA.
- A cell is subdivided to a sure number of fields, every one of which “is illuminated” from an antenna directive (or panel), that is an antenna that “does not illuminate” in all the directions, but concentrates the flow of power within a particular area of the cell, known as sector. Every field can therefore be considered like one new cell. By using directional antennas, the co-channel interference is reduced. A typical structure is the trisector, also known as clover, in which there are 3 sectors, each one served by separate antennas. Every sector has a separate direction of tracking of 120° with respect to the adjacent ones. If not sectorised, the cell will be served by an omnidirectional antenna, which radiates in all directions. Bisectored cells are also implemented with the antennas serving sectors of 180° separation to one another.
See also [सम्पादन गर्ने]
References [सम्पादन गर्ने]
|यस लेखलाई विकिको मापदण्ड अनुसारको विश्वसनीय बनाउन .अधिक स्रोत खुलाउन आवश्यक देखिन्छ
कृपया विश्वस्त स्रोत जोडेर सुधार्नको निम्ति सहायता गर्नुहोस्। विश्वस्त स्रोत उल्लेख नभएको पृष्ठमाथि चुनौती आई पर्न सक्छ र सधैंका लागि मेटाउन पनि सकिने छ. (June 2008)
Further reading [सम्पादन गर्ने]
- Satoshi Maruyama, Katsuhiko Tanahashi, Takehiko Higuchi (2002), Base Transceiver Station for W-CDMA System, FUJITSU Sci. Tech. J, pp. 7, <http://www.fujitsu.com/downloads/MAG/vol38-2/paper07.pdf>
|विकिमीडिया कमन्समा अरु धेरै सामाग्रीहरू छन्: Base station|