KR20030049407A - Apparatus of base station in mobile telecommunication system - Google Patents

Abstract

PURPOSE: A base station device for a mobile communication system is provided to solve the degradation of speech quality and the restriction of a transmission distance, which are caused by a conventional repeater. CONSTITUTION: A channel card(BCEA)(200) transmits a transmission signal to a summing/IF(Intermediate Frequency) unit(210). The summing/IF(Intermediate Frequency) unit(210) receives the transmission signal, and transmits the received transmission signal to an optical multiplexing/demultiplexing unit(220). The optical multiplexing/demultiplexing unit(220) receives the summed signal, multiplexes the received signal, and transmits the multiplexed signal through an optic fiber(230). Remote RF(Radio Frequency) devices(100-1 to 100-n) connect to the optical multiplexing/demultiplexing unit(220) through the optic fiber(230).

Description

Base station apparatus of mobile communication system {APPARATUS OF BASE STATION IN MOBILE TELECOMMUNICATION SYSTEM}

The present invention relates to a mobile communication system, and more particularly, to a base station apparatus of a mobile communication system.

The base station apparatus is a component of the mobile communication network and performs a function of connecting a terminal to the network. Various types of base station apparatuses are required for a service in a mobile communication system including IMT-2000. The various base station apparatuses may include a micro base station apparatus, a pico base station apparatus, an outdoor base station apparatus, a subway type base station apparatus, and the like, which are stationed at a special site, in addition to the macro base station apparatus. In addition, a repeater may be used for coverage that is difficult to service with the base station devices, that is, shadow area and coverage of the base station device.

On the other hand, with the development of mobile communication, base station devices that were installed mainly in large cities tend to be additionally installed on the outskirts and small cities, towns, villages, roadsides, buildings where radio waves are difficult to reach. In addition, depending on the expected number of subscribers, the environment of the wireless network, and economic conditions or the like, a repeater may be installed in some regions instead of the base station apparatus.

By the way, the conventional analog repeater is configured to receive a signal from a base station apparatus, which is a main station, through a radio or optical path, and simply amplify and transmit the received signal. As a result, the upper layer recognizes each of the repeaters connected to the same base station device as the same cell, and thus there is a weak point in providing location information service.

In addition, since the conventional repeater transmits an analog signal in the intermediate frequency stage and the radio frequency stage, the transmission distance is limited, and the call quality using the repeater is inferior to the call quality when using the base station apparatus.

Accordingly, an object of the present invention is to provide a repeater device capable of eliminating the call quality degradation and transmission distance constraints of the conventional repeater.

Another object of the present invention is to provide a relay device capable of resolving inaccurate position information due to a repeater when providing a location information service.

It is still another object of the present invention to provide a relay apparatus that enables a base station apparatus to flexibly respond to changes in a wireless network environment.

In order to achieve the above objects, the present invention provides a channel card for outputting a transmission signal and transmitting to a summing / intermediate frequency unit, and a summing / intermediate frequency unit for receiving and summing the signal and transmitting it to an optical multiplexing / demultiplexing unit, and A base station apparatus comprising: an optical multiplexer / demultiplexer for receiving a summed signal, multiplexing the same, and transmitting the optical signal through an optical transmission path; and a remote radio frequency device connected to the optical multiplexer / demultiplexer through the optical transmission path. Use

1 is a diagram illustrating transmission and reception wavelength allocation for each remote radio frequency device connected to a main unit of a base station apparatus according to the present invention.

2 is a view according to the present invention, the entire base station configuration diagram

3A and 3B illustrate a summing part among summing / intermediate frequency parts constituting the base station.

FIG. 4 is a diagram illustrating an intermediate frequency part among the summing / intermediate frequency parts configuring the base station.

5 and 6 are forward transmission configuration (channel card (BCEA)-> intermediate frequency integrated board) and reverse transmission configuration (channel card <-intermediate frequency integrated board) through a channel card and a digital intermediate frequency integrated board (DTRA), respectively. Drawing

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the reference numerals to the components of the drawings, it should be noted that the same reference numerals as much as possible even if displayed on different drawings. On the other hand, in the following description of the present invention, when indicating a specific device by using a reference numeral, when the specific device may be provided with a plurality of devices, it is not necessary to distinguish each of the devices in particular The devices are referred to by their representative reference numerals. Referring to FIG. 1 to be described below, when the remote radio frequency device 1 to the remote radio frequency device n (100-1 to 100-n) does not need to distinguish between the remote radio frequency devices as the representative symbol 100 Directs everything.

The present invention is to implement a new type of base station apparatus that can flexibly cope with changes in the wireless network environment. To this end, since the remote RF device of the base station apparatus proposed by the present invention is installed outside the main unit, it can flexibly cope with the coverage change due to the introduction of data service in the future. Unlike the repeaters, the remote radio frequency devices can be managed by cell unit, which is also suitable for providing location related services. In addition, by configuring the capacity of the remote radio frequency device can be expanded from the minimum capacity to the maximum capacity, it is possible to meet various wireless network design requirements. In the following, the present invention is described by describing a base station apparatus of a W-CDMA system.

1 is a diagram illustrating transmission and reception wavelength allocation for each remote radio frequency device connected to a main unit of a base station apparatus according to the present invention.

Modems for asynchronous base station devices support 12 independent transmit and receive paths, including transmit and receive diversity. In addition, the basic configuration of each base station apparatus can be operated by mounting a channel card of 2FA (Frequency Assignment) / 3Sector or 1FA / 6Sector in a pool form. Depending on the characteristics of the installation site, choose an advantageous form among the multiple implementation of the FA or the multiple implementation of the sector. The base station apparatus can be expanded in units of FA or sectors.

When the base station apparatus is expanded to the maximum, it has a capacity of 2FA / 6Sector, which means that 12 base stations (12 cells) can be installed in units of cells. Installing a plurality of base station devices as described above is particularly advantageous for securing coverage in large cities such as shadow areas and suburban areas.

To this end, a single board includes a block that performs a function of summing the digital output signal of the channel card of the base station apparatus and optically transmits the signal and transmits a received signal to the channel card. Can be. In the optical transmission of the summed output signal, a wavelength division multiplex (WDM) using wavelength selectivity of an optical device is used. The wavelength division multiplexing method is a method of transmitting a plurality of optical signals having different wavelengths through one optical transmission path. In the optical transmission, since several optical signal wavelengths are used at the same time, the bandwidth provided by the optical transmission path can be effectively used. In addition, in the wavelength division multiplexing method, since the wavelength is different, the speed transmitted to the optical transmission path is independent of the speed of individual equipment.

In the configuration as described above, since independent addition and drop of wavelengths are possible for each cell through optical add & drop (WAD), efficient cell management is possible. On the other hand, as an embodiment for solving the problem of device limitation due to economical efficiency, it is possible to bundle the transmission signal of several cells and transmit in one wavelength, and up to eight independent wavelengths can be used for the received signal. That is, the transmission network of the base station apparatus of the present invention can improve economics by using a combination of DWDM (Dense WDM) and CWDM (Coarse WDM) to the transmission and reception paths, respectively. The available (economical) wavelength is DWDM, and the CWDM method is used for wavelengths that are less economical. The DWDM method may be implemented using a cooled DFB LD (Distributed FeedBack Laser Diode), and the CWDM method may be implemented using an Uncooled DFB LD. As an example, the DWDM may use 1530 to 1570 nm, and CWDM may use 1470, 1490, 1510, 1530, 1550, 1570, 1610nm, and 1310nm. In general, when implementing a base station apparatus in a wavelength division multiplexing scheme, two transmission wavelengths and eight reception wavelengths are used. Multi Drop can support up to 8 independent cells.

2 is a diagram according to the present invention, which is a block diagram of an entire base station.

As shown in FIG. 2, the base station of the present invention includes a channel card (BCEA) 200, a summing / intermediate frequency unit (Summing / IF) 210, and an optical multiplexing / demultiplexing unit (Optical MUX / DEMUX) 220. And a remote radio frequency device 100 connected to the multiplexing / demultiplexing unit 220 through the optical transmission path 230 and the optical transmission path 230.

3A and 3B illustrate a summing part among the summing / intermediate frequency parts.

3A shows an example of 1FA / 6 cells, and FIG. 3B shows an example of 2FA / 6 cells. The signal output from the channel card 200 to the summing unit is transmitted through a summing and multiplexing process. The summing unit is a device for forward signal transmission. A signal corresponding to up to six cells (sectors) for each FA is loaded on one optical wavelength through the summing unit and transmitted to the remote RF device 100.

FIG. 4 is a diagram illustrating an intermediate frequency part among the summing / intermediate frequency parts of FIG. 2.

The signal received from the remote radio frequency device 100 of at least one cell is demultiplexed in the intermediate frequency unit and converted into an intermediate frequency (IF) signal and output to the channel card 200. The intermediate frequency unit is used for reverse signal transmission, and transmits a signal received from at least one remote radio frequency device 100 to the channel card 200.

5 and 6 illustrate a forward transmission configuration (channel card-> intermediate frequency integrated board) and a reverse transmission configuration (channel card <-intermediate frequency integrated board) through a channel card and a digital intermediate frequency integrated board (DTRA), respectively. Drawing.

The digital intermediate frequency integrated board of FIGS. 5 and 6 performs two functions of summing the digital output signal of the channel card and optically transmitting it, summing the transmission signal, and distributing the received signal to the channel card. Means. That is, the digital intermediate frequency integrated board corresponds to the summing / intermediate frequency unit 210.

Hereinafter, the operation of the present invention will be described in detail with reference to FIGS. 1 to 6.

The transmission signal output from each channel card 200 is transmitted to the summing / intermediate frequency board 210. The signal is a baseband signal (in particular, a baseband signal having an I / Q phase), and transmit diversity may be considered. All of the channel cards 200 can be operated by pooling the FA / Sector, and the output corresponding to 1FA / 6Sector is transmitted to the summing / intermediate frequency unit 210. Obviously, it is not necessary to limit the 6FA to 6Sector.

The summing / intermediate frequency unit 210 separates the signal transmitted from each channel card 200 for each sector. The separated signal is a transmission signal for one cell, and this signal is converted to E / O (Electric / Optical) and multiplexed through the multiplexer 220 to the remote radio frequency device 100 through the optical transmission line 230. Is sent. The remote radio frequency device 100 selects the FA / Sector signal assigned to the O / E and transmits the same to the transceiver board. The signal is amplified by the power amplifier to the required intensity and output through the antenna stage. The power amplifier may select HPA or LPA according to the base station environment, and the output may be variously selected. On the other hand, for the received signal, the received signal considering the diversity is transmitted to the demultiplexer 220 through the optical transmission path, and the demultiplexed received signal is converted to the summing / intermediate frequency unit 210 after O / E conversion. Via each channel card 200 via.

For example, the bandwidth and the like required to implement the present invention are obtained as follows. It is assumed that the channel card 200 supports 80 channels, respectively, and the digital intermediate frequency integrated board has a structure supporting a capacity of 1FA / 1Sector. The digital baseband interface of the channel card 200 and the digital intermediate frequency integrated board may consist of a CDMA forward data bus and a reverse data bus. The forward data bus and the reverse data bus may be referred to as a baseband transmit data bus and a baseband receive data bus, respectively. The bandwidth required for implementing the transmit / receive data bus connecting the channel card 200 and the digital intermediate frequency integrated board as an optical transmission path is as follows.

The data per FA / Sector of the transmit data bus should be configured to include transmit bits and 16 bits, 1FA / 1 sector, and I / Q.

The throughput in this case is 3.84 Mcps x 2 (A / B) x 2 (I / Q) x 16 bits = 245.76 Mbps. Therefore, the transmission bandwidth required for processing 4FA / Omni is 245.76Mbps × 4 = 983.04Mbps, and the transmission bandwidth required for processing sFA / 6Sector is 245.76Mbps × 2 × 6 = 2,949.12Mbps.

On the other hand, the data of the receive data bus is 4-bit, 4over-sampling including receive diversity. The required bandwidth is 122.88Mbpx for I / Q, respectively, and the reception diversity required for processing 2FA / 6Sector is 245.76Mbps × 2 × 6 = 2,949.12Mbps.

On the other hand, in the above description of the present invention, the specific number specified for the transmission and reception wavelengths and the like is for ease of explanation, and it is obvious that the present invention is not limited to the above specification.

By implementing the present invention as described above it is possible to implement a base station apparatus device that is easy to adapt to changes in the radio network. It is possible to implement a base station apparatus device that provides location information service, is not limited in transmission distance, and provides good call quality.

Claims (2)

In the base station apparatus device of the mobile communication system, A channel card that outputs a transmission signal and transmits it to the summing / intermediate frequency unit; A summing / intermediate frequency unit for receiving the signal and summing it and transmitting to the optical multiplexer / demultiplexer; An optical multiplexer / demultiplexer for receiving the summed signal, multiplexing the same, and transmitting the multiplexed signal through an optical transmission path; And a remote radio frequency device connected to the optical multiplexer / demultiplexer through the optical transmission path. A base station apparatus of a mobile communication system, An optical multiplexer / demultiplexer for demultiplexing a signal received from a remote radio frequency device connected through an optical transmission path; And a summing / intermediate frequency unit for receiving the demultiplexed signal, converting the signal into an intermediate frequency signal, and distributing the signal to a channel card.