KR200360398Y1 - Digital Transceiver of Base station for cellular system - Google Patents

Abstract

The present invention relates to a digital transceiver of a mobile communication base station which reduces transmission loss and costs by dividing into a master device installed indoors and a slave device installed outdoors. The apparatus of the present invention is a base station apparatus for mobile communication, comprising: a master apparatus installed in a building, connected to an exchange station, and communicating with a slave apparatus in a digital manner; A base station antenna installed outdoors; A slave device installed near the antenna and connected to the antenna by a coaxial cable and communicating with the master device in a digital manner; And a UTP cable for connecting the master device and the slave device. Therefore, according to the present invention, when the base station device is installed, the master device is placed in the building, and the slave device is located near the outdoor antenna, and the existing coaxial cable is connected by connecting the master device and the slave device with a low cost UTP cable and communicating digitally. Compared to the used method, the high frequency loss is reduced to about 1/11, the high frequency transmission and reception noise is reduced to about 1/10, and the cable cost is also reduced to about 1/4, thereby providing high quality service at low cost.

Description

Digital transceiver of mobile communication base station {Digital Transceiver of Base station for cellular system}

The present invention relates to a base station apparatus of a mobile communication network, and more specifically, to digital transmission and reception of a mobile communication base station which reduces transmission loss and cost by dividing into a master apparatus installed indoors and a slave apparatus installed outdoors. Relates to a device.

In general, a mobile communication network is composed of an exchange station, a base station controller, a base station, and the like, and transmits a forward signal received from the exchange station to the subscriber side through the base station, and also transmits a reverse signal received from the subscriber to the exchange station side through the base station.

In such a mobile communication network, a conventional base station apparatus receives a forward subscriber signal transmitted from an exchange station, encodes it, modulates it, converts it to an intermediate frequency (IF) or a high frequency at low power, amplifies it with a high frequency amplifier, and then uses an external roof or high ground. It transmits through coaxial cable to the antenna installed in the pylon, and the reverse subscriber signal received from the subscriber through the antenna is amplified by low noise and then introduced into the base station equipment in the building through the coaxial cable, demodulated, converted to an intermediate frequency, decoded, and transmitted to the switching center. It is.

Therefore, in the conventional base station apparatus, the length of the coaxial cable connecting the antenna installed in the tower and the base station apparatus installed in the building is long so that approximately 1/10 of the transmission signal is attenuated by the cable loss, and the low noise amplifier also receives an input loss. There is a problem that the noise increases a lot. In addition, the coaxial cable is consumed a lot, there is a problem that the cost of installing the base station is also expensive.

The present invention has been made to solve the above problems, by installing a slave device near the base station antenna to connect a short coaxial cable or direct connection, and the low cost UTP cable between the master device and the slave device located in the building It is an object of the present invention to provide a digital transceiver of a mobile communication base station which greatly reduces signal loss and cost by transmitting a signal in a post-digital manner.

1 is a conceptual diagram illustrating a digital transceiver of a mobile communication base station according to the present invention;

2 is a block diagram illustrating a digital transceiver of a mobile communication base station according to the present invention;

* Explanation of symbols for main parts of the drawings

10: master device 20: slave device

31 ₁ , 31 ₂ , 31 ₃ : transmitting antenna 32 ₁ , 32 ₂ , 32 ₃ : main receiving antenna

32 ' ₁ , 32' ₂ , 32 ' ₃ : Diversity receiving antenna

40-1 to 40-n: UTP cable

11 ₁ ~ 11 _n : Down converter 12 ₁ ~ 12 _n : Up converter

12 ' ₁ ~ 12' _n : Up-converter for diversity 13 ₁ ~ 13 _n : Analog-to-digital converter

14 ₁ ~ 14 _n : Digital to Analog Converter

14 ' ₁ ~ 14' _n : Digital to analog converter for diversity

15: Programmable Logic Array for Master

16 ₁ ~ 16 _n : Ethernet encoder / decoder for master

26 ₁ ~ 26 _n : Ethernet encoder / decoder for slave

25: programmable logic array for slave

23 ₁ to 23 _n : Digital to analog converter

21 ₁ ~ 21 _n : Up-converter 27 ₁ ~ 27 _n : High Frequency High Power Amplifier

28 ₁ to 28 _n : Low noise amplifier 28 ' ₁ to 28' _n : Diversity low noise amplifier

22 ₁ ~ 22 _n : Down converter 22 ' ₁ ~ 22' _n : Diversity down converter

24 ₁ to 24 _n : Analog Digital Converter

24 ' ₁ ~ 24' _n : Diversity analog to digital converter

17,29: controller

In order to achieve the above object, the device of the present invention, a base station device for mobile communication, installed in the building connected to the switching center and the master device for communicating with the slave device in a digital manner; A base station antenna installed outdoors; A slave device installed near the antenna and connected to the antenna by a coaxial cable and communicating with the master device in a digital manner; And it characterized in that it comprises a UTP cable for connecting the master device and the slave device.

Here, the master device includes an analog digital converter for converting a forward intermediate frequency signal or a high frequency signal into digital; A digital analog converter for converting reverse digital data into an intermediate frequency or high frequency signal; A programmable logic array that sums the digitally converted forward data streams and distributes the reverse data streams; An Ethernet encoder / decoder for master encoding the forward output of the programmable logic array and transmitting it through the UTP cable and decoding and reproducing the digital signal received through the UTP cable; And a master controller for monitoring and controlling the operation state of each unit.

The slave device may further include an Ethernet encoder / decoder for encoding and decoding digital data to transmit and receive data to and from the master device through a UTP cable; A programmable logic array that distributes the forward data stream reproduced through the Ethernet encoder / decoder and adds backward data to the Ethernet encoder / decoder; A digital analog converter for converting the distributed forward digital data into an intermediate frequency or high frequency signal; An up-converter converting the forward intermediate frequency signal into a high frequency signal; A high frequency high output amplifier amplifying the forward high frequency signal and outputting the same through a transmitting antenna; A low noise amplifier for amplifying the signal received from the receiving antenna; A down converter converting a reverse high frequency signal into an intermediate frequency signal; And an analog digital converter for converting a reverse intermediate frequency signal or a high frequency signal into a digital signal and delivering the same to the programmable logic array.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Typically, the base station apparatus may use one omni-directional antenna, but may also be implemented by using a 2 to N sector antenna having directivity. For convenience of description, an embodiment of the present invention is a three sector antenna and a diversity scheme using two reception antennas for each sector will be described as an example.

1 is a schematic diagram showing a digital transceiver of a mobile communication base station according to the present invention.

As shown in FIG. 1, the base station apparatus according to the present invention is installed in a building 2, connected to an exchange office, and connected to a master apparatus 10 that communicates with a slave apparatus 20 in a digital manner, and to an outdoor pylon 4. Installed base station antennas (31 ₁ , 31 ₂ , 31 ₃ , 32 ₁ , 32 ₂ , 32 ₃ , 32 ' ₁ , 32' ₂ , 32 ' ₃ ), installed near the base station antennas and connected by short cable or directly to the antenna And a low cost general telephone line UTP cable 40-1 to 40-3 for connecting the master device 10 and the slave device 20 in digital communication with the master device 10. It is composed.

Referring to FIG. 1, the base station antennas 31 ₁ , 31 ₂ , 31 ₃ , 32 ₁ , 32 ₂ , 32 ₃ , 32 ' ₁ , 32' ₂ , 32 ' ₃ are divided into three sectors, and each sector is one. The transmit antenna and two receive antennas are in service. In the embodiment of the present invention, each sector is divided into subscripts indicated at the bottom of the reference numeral, and the diversity antenna is denoted by attaching "'" to the reference numeral.

The slave device 20 is installed near the base station antenna and is connected to the antenna by a short coaxial cable, and is connected to the master device 10 by UTP cables 40-1 to 40-3 for each sector. In the embodiment of the present invention, since it is a three sector antenna structure, it is connected by three UTP cables 40-1 to 40-3.

In the present invention, since the master device 10 and the slave device 20 transmit signals in a digital manner, there is no loss even when using the UTP cables 40-1 to 40-3, and the slave device 20 and the antenna Use very short coaxial cables or connect directly, so there is little cable loss.

2 is a block diagram illustrating a digital transceiver of a mobile communication base station according to the present invention, and a detailed block diagram of a slave device 20 installed near a master device 10 and a base station antenna 30 installed in a building is shown. Is shown.

Referring to FIG. 2, the forward data received from the switching center is encoded and modulated by the sector-specific high frequency or intermediate frequency transmitters T ₁ to T _n in a normal base station, and thus each master apparatus 10 according to the present invention for each sector. Is entered.

As shown in FIG. 2, the master device 10 according to the present invention is composed of N sector parts that are identically configured for each sector, and each sector part has a down converter 11 ₁ for converting a forward high frequency signal into an intermediate frequency signal. 11 _n ), an analog digital converter 13 ₁ to 13 _n for converting a forward intermediate frequency signal (or a high frequency signal) to digital, and a digital analog converter for converting reverse digital data to an intermediate frequency signal (or a high frequency signal) ( 14 ₁ to 14 _n ), an up-converter 12 ₁ to 12 _n for converting a reverse intermediate frequency signal into a high frequency signal and providing the receiver R ₁ to R _n , and converting reverse digital data into an intermediate frequency signal (or a high frequency signal). Digital analog converter (13 ' ₁ to 13' _n ) for diversity conversion and diversity upconverter (12 ₁ ) for converting reverse intermediate frequency signal into high frequency signal and providing it to receiver (R ' ₁ to R' _n ). ~ 12 _n), digital The output of the programmable logic array 15 and the programmable logic array 15 for summing the forward data streams converted into the PDUs and distributing the reverse data streams received from the slave side through the UTP cables 40-1 to 40-n. transmission and is configured as a master Ethernet encoder / decoder (16 ₁ ~ 16 _n) for decoding and reproducing the received signal through the UTP cable (40-1 ~ 40-n). Each sector is controlled by the controller 17. When the intermediate frequency signal is inputted from the high frequency or intermediate frequency transmitters T ₁ to T _n , the down converters 11 ₁ to 11 _n or the up converter 12 ₁ are shown as dotted lines. It is also possible to bypass without using ~ 12 _n , 12 ' ₁ ~ 12' _n ).

In addition, as shown in FIG. 2, the slave device 20 according to the present invention includes N sector parts configured identically to each sector. Each sector part encodes an output of the programmable logic array 25 to form a UTP cable ( Ethernet encoders / decoders (26 ₁ to 26 _n ) for slaves that transmit via 40-1 to 40-n and decode and play signals received through UTP cables 40-1 to 40- _n , and digitally for the combined uplink data stream converted transmitted to the master, and converts the forward data a programmable logic array 25, the forward digital data for distributing the stream received from the master side to an intermediate frequency (or high-frequency signal), the digital to analog converter (23 ₁ - 23 _n ), upconverters 21 ₁ to 21 _n for converting forward intermediate frequency signals to high frequency signals, and high frequency extraction for amplifying the forward high frequency signals and outputting them through a transmitting antenna. Power amplifiers 27 ₁ to 27 _n , low noise amplifiers 28 ₁ to 28 _n for amplifying the reverse signals received from the main receiving antennas, and low noise amplifiers 28 'for diversity amplifying the signals received from the diversity receiver antennas. ₁ to 28 ' _n ), down converter (22 ₁ to 22 _n ) for converting reverse high frequency signal to intermediate frequency signal, and down converter (22' ₁ to 22 ' _n for diversity converting reverse high frequency signal to intermediate frequency signal) ), An analog digital converter 24 ₁ to 24 _n for converting a reverse intermediate frequency signal (or a high frequency signal) to digital, and an analog digital converter 24 'for diversity converting a reverse intermediate frequency signal (or a high frequency signal) to digital. ₁ to 24 ' _n ). Each sector portion is controlled by the slave controller 29 and communicates with the controller 17 on the master side to exchange information with each other to facilitate maintenance. These controllers 17 and 29 can also monitor and adjust the operating status of the master and slave (eg, output, temperature, power failure, other environments, etc.), including a monitoring device.

In addition, when the present invention is applied to one sector or a small number of sectors, a repeater, or the like, the programmable logic arrays 15 and 25 of the master and the slave may be omitted.

Next, the operation of the apparatus according to the present invention configured as described above will be described by dividing the forward and reverse directions.

[Forward signal transmission]

In order to provide mobile communication services (data, voice, video) using high frequencies such as VHF, UHF, and microwave, the forward subscriber signals transmitted from the switching center are received by the base station in the building, encoded and modulated, and then used as high-frequency signals to serve at high frequencies. Are input to the master device 10 according to the present invention.

The down converters 11 ₁ to 11 _n of the master device according to the present invention down the intermediate frequency signal when the input signal is a high frequency signal and bypass the intermediate frequency signal as it is. The analog digital converters 13 ₁ to 13 _n convert the forward intermediate frequency signals inputted from the down converters 11 ₁ to 11 _n to digital, and the programmable logic array 15 converts the analog digital converters 13 ₁ to ₁ to each sector. 13 _n ) processes the transmission data transmitted from 13 _n ) to form a forward data stream for each sector, and transmits the data to the corresponding Ethernet encoders / decoders 16 ₁ to 16 _n . And it transmits to each Ethernet encoder / decoder (16 ₁ ~ 16 _n) is the slave device 20 through the UTP tables (40-1 ~ 40-n) and encodes the forward data stream received.

According to the present invention, the slave device 20 installed near the antenna receives forward data received from the master device 10 through the UTP cables 40-1 to 40-n with the Ethernet encoder / decoder 26 ₁ to 26 _n . Decode and transfer to programmable logic array 25. The programmable logic array 25 distributes the forward transmission data received from each Ethernet encoder / decoder 26 ₁ to 26 _n and transfers it to the digital analog converters 23 ₁ to 23 _n of the corresponding sectors. 23 ₁ to 23 _n ) converts the received forward digital signal into an intermediate frequency signal. And up-converter (21 ₁ ~ 21 _n) is then converted to a forward intermediate frequency signal to a radio frequency signal transmitted to the high-frequency high-power amplifier (27 ₁ ~ 27 _n), and a high-frequency high-power amplifier (27 ₁ ~ 27 _n) includes a forward high-frequency signal Amplifies and transmits the signal to the subscriber through the transmission antennas 31 ₁ to 31 _n .

[Reverse signal transmission]

On the other hand, the reverse signal transmitted from the subscriber station to the base station apparatus is received through the main receiving antennas 32 ₁ to 32 _n and the receiving antennas 32 ' ₁ to 32' _n for diversity. The reverse signal received through the main receiving antennas 32 ₁ to 32 _n is amplified by the low noise amplifiers 28 ₁ to 28 _n of the slave device and then converted into an intermediate frequency signal by the down converters 22 ₁ to 22 _n . The received signal converted into the intermediate frequency signal is converted into digital data by the analog digital converters 24 ₁ to 24 _n and input to the programmable logic array 25. Meanwhile, the signal received through the diversity receiver antennas 32 ' ₁ to 32' _n is amplified by the corresponding low noise amplifiers 28 ' ₁ to 28' _n and then the corresponding down converters 22 ' ₁ to 22' _n . It is converted into an intermediate frequency signal. The received signal converted into the intermediate frequency signal is converted into digital data by the analog digital converters 24 ₁ to 24 _n and input to the programmable logic array 25. As described above, in the reverse path, since the main reception signal and the diversity reception signal operate in the same manner, the main reception signal will be described for convenience of description.

The programmable logic array 25 of the slave device processes the reverse digital data input from the analog digital converters 24 ₁ to 24 _n of each sector, and transmits the reversed digital data to the Ethernet encoder / decoder 26 ₁ to 26 _n of the corresponding sector. Ethernet encoders / decoders (26 ₁ to 26 _n ) of the sector encode the received reverse digital data and over the UTP cables (40-1 to 40-n) the Ethernet encoder / decoder (16 ₁ to 16 _n ) of the master device. To send.

The Ethernet encoder / decoder 16 ₁ to 16 _n of the master device installed in the building decodes the reverse signal received through the UTP cable 40-1 to 40-n to the programmable logic array 15, and the programmable logic. array 15 is the allocation of the received uplink data stream to the digital-to-analog converter (14 ₁ ~ 14 _n) of each sector.

The digital-to-analog converters 14 ₁ to 14 _n convert the received digital data into reverse intermediate frequency signals and transmit them to the up-converters 12 ₁ to 12 _n . The up-converters 12 ₁ to 12 _{n are} connected to a base station receiver. When receiving the high frequency reception, converts the intermediate frequency signal into a high frequency signal and transmits the signal. When receiving the intermediate frequency signal, the reverse intermediate frequency signal received from the digital analog converter 14 ₁ to 14 _n is bypassed. Transfer to the base station receiver (R ₁ ~ R _n ).

On the other hand, the controller 17 of the master device and the controller 29 of the slave device transmit data according to a predetermined protocol to provide operation status information, and the controller 17 of the master device provides this information to the switching center device. Easy maintenance

As described above, according to the present invention, when installing the base station device, the master device is placed in the building, and the slave device is located near the outdoor antenna, and then the low cost UTP cable is connected between the master device and the slave device and the digital communication is performed. Compared with the conventional coaxial cable method, the high frequency loss is reduced to about 1/11, the high frequency transmission and reception noise is reduced to about 1/10, and the cable cost is reduced to about 1/4 so that high quality service can be provided at low cost. have.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art various modifications and variations of the present invention without departing from the spirit and scope of the present invention described in the claims below I can understand that you can.

Claims (11)

In the base station apparatus for mobile communication, A master device installed in the building, connected to the switching center and communicating with the slave device in a digital manner; A base station antenna installed outdoors; A slave device installed near the antenna via a coaxial cable or directly connected to the antenna, the slave device communicating digitally with the master device; And And a UTP cable for connecting the master device and the slave device. The method of claim 1, wherein the master device An analog digital converter for converting a forward intermediate frequency signal or a high frequency signal into digital; A digital analog converter for converting reverse digital data into an intermediate frequency or high frequency signal; An Ethernet encoder / decoder for master encoding the forward output of the digital analog converter and transmitting it through the UTP cable, and decoding and reproducing the digital signal received through the UTP cable; And And a master controller for monitoring and controlling the operation state of each unit. The method of claim 2, wherein the master device In the case of a multi-sector implementation, the digitally converted forward data streams are combined and transmitted to the master Ethernet encoder / decoder, and the reverse data streams received from the master Ethernet encoder / decoder are distributed to the digital analog converter of each sector. Digital transceiver of the mobile communication base station further comprising a programmable logic array to provide. The method of claim 2, wherein the master device A down converter for converting the forward high frequency signal received from the switching center into an intermediate frequency signal; And an up-converter for converting a reverse intermediate frequency signal received from the digital analog converter into a high frequency signal. The method of claim 2, wherein the master device If the base station is implemented in an N sector manner, And the analog digital converter, the digital analog converter, and the ethernet encoder / decoder for each sector. The method of claim 2, wherein the master device When using the receive diversity method, And a digital analog converter for diversity, and an upconverter for diversity. The method of claim 1, wherein the slave device is An Ethernet encoder / decoder for the slave that encodes and decodes the digital data to transmit and receive data via the UTP cable with the master device; A digital analog converter for converting the decoded forward digital data into an intermediate frequency or high frequency signal; An up-converter converting the forward intermediate frequency signal into a high frequency signal; A high frequency high output amplifier amplifying the forward high frequency signal and outputting the same through a transmitting antenna; A low noise amplifier for amplifying the signal received from the receiving antenna; A down converter converting a reverse high frequency signal into an intermediate frequency signal; An analog digital converter for converting the reverse intermediate frequency signal or the high frequency signal into digital; And And a slave controller for monitoring and controlling the operation state of each unit. The method of claim 7, wherein the slave device is When implemented in the multiple sectors, the forward data stream reproduced through the Ethernet encoder / decoder is distributed to the digital analog converter of each sector, and the reverse data inputted from the analog digital converter of each sector is added to the Ethernet encoder. Digital transceiver of the mobile communication base station further comprises a programmable logic array for transmitting to / decoder. The method of claim 7, wherein the slave device is If the base station is implemented in an N sector manner, For each sector And a slave Ethernet encoder / decoder, the digital analog converter, the up converter, the high frequency high output amplifier, the low noise amplifier, the down converter, and the analog digital converter. Digital transceiver. The method of claim 7, wherein the slave device is When using the receive diversity method, A digital transceiver for a mobile communication base station, characterized by further comprising: a low noise amplifier for diversity, a down converter for diversity, and an analog digital converter for diversity, for amplifying a signal received from a diversity reception antenna. The apparatus of claim 1, wherein the digital transceiver is Digital transmitting and receiving device of a mobile communication base station, characterized in that configured to communicate in only one of the forward or reverse direction.