KR20090039543A - Multi-in multi out based in-building rf system and method, and apparatus applied to the same - Google Patents

Abstract

A multi-in and multi-out based in-building rf system and a method, and apparatus applied to the same are provided to implement a mobile communication service at the in-building region supporting MIMO(Multi-In and Multi-Out) without the construction of the additional cable for the in-building RF system. An in-building RF system based on Multi-In Multi-Out comprises an in-building Radio Frequency Hub unit(200), a remote unit(300), and up down converter Amp Module unit(400). The in-building Radio Frequency Hub unit classifies the frequency of the more than two carrier signals provided from the base station(100). The in-building Radio Frequency Hub unit converts the frequency between the corresponding carrier signals in order to be differentiated. The in-building Radio Frequency Hub unit transmits the carrier signal of the frequency-converted to a cable within in-building.

Description

MULTI-IN MULTI OUT BASED IN-BUILDING RF SYSTEM AND METHOD, AND APPARATUS APPLIEDUS THE LIMITED TO THE SAME

The present invention relates to an in-building RF technology based on multi-in multi-out. More particularly, the present invention relates to a multi-input multi-output service without additional cable construction. The present invention relates to a multi-input multi-output based in-building RF system and method for implementing a mobile communication service in an in-building area, and an apparatus applied thereto.

In general, a mobile communication service system includes a base station, a base station controller, an exchange station, and a mobile communication terminal. Here, the base station and the mobile communication terminal communicates in a constant frequency band, each base station has a constant call radius cell. Therefore, by appropriately arranging each base station so that the call radius of each base station overlaps each other, the area where the call is possible can be expanded.

However, even if the service area is covered by the arrangement of such a plurality of base stations, a call shade area that is impossible to call occurs in island areas, underground spaces of large buildings, and inside skyscrapers. As a way to solve the problems caused by the occurrence of the call shadow area, the shadow area was solved by installing a repeater in the shadow area.

Furthermore, the shaded area includes an in-building area inside the building, and a separate in-building RF system is required to smoothly support mobile communication services in the in-building.

In the case of such an in-building RF system, since the cable in the in-building is constructed as one cable, the structure of 1Tx-1Rx is mostly because the Tx-Rx signal must be simultaneously transmitted through one cable.

Accordingly, the Tx signal or the Rx signal, which can be separated by frequency (FDD system) or time (TDD system), can be carried on one cable to provide a mobile communication service, but two or more Tx signals or two or more of the same frequency or time can be used. Since Rx signals cannot be carried on a single cable, it is difficult to implement a multi-input multiple output service of 2Tx-2Rx or more in a conventional in-building RF system in which a single cable is installed.

Accordingly, the present invention has been made to solve the above problems, and an object of the present invention is to provide mobile communication in an in-building area based on a multi-input multi-output service without additionally constructing cables of multiple lines. A multi-input multi-output based in-building RF system and method for implementing a service, and an apparatus applied thereto.

Another object of the present invention is to provide a multi-input multi-output based in-building RF system and method for implementing a mobile communication service supporting a multi-input multi-output service through a single cable already constructed in the in-building. And to provide an apparatus applied thereto.

In order to achieve the above object, a multi-input multi-output based in-building RF system according to a first aspect of the present invention distinguishes whether or not frequencies are equal to at least two transmission signals provided from a base station, and between corresponding transmission signals. An in-building RF hub for converting the frequencies to be discriminated from one another and transmitting them to a cable in the in-building; outputting the at least two or more transmission signals provided through the cable to a port corresponding to a service allocation area and a remote transmission area; Receiving the at least two transmission signals from at least one remote unit for outputting to a port corresponding to and receiving at least two transmission signals from a port corresponding to the service allocation area, and outputting at a service frequency to radiate through an antenna that is directed to the service allocation area At least one UAM portion for Shall be.

Preferably, the in-building RF hub portion is characterized in that for setting the frequency band for conversion based on the line loss rate in the cable.

Preferably, the remote unit converts at least one transmission signal of the at least one transmission signal into a service frequency for providing the service allocation area and outputs it to a port corresponding to the service allocation area.

Preferably, the UAM unit bypasses a transmission signal converted to a service frequency among the at least two transmission signals provided from a port corresponding to the service allocation region and radiates it to the service allocation region through a corresponding antenna. It is done.

Preferably, the UAM unit converts a transmission signal unconverted into a service frequency among the at least two or more transmission signals provided from a port corresponding to the service allocation area to a service frequency and radiates it to the service allocation area through a corresponding antenna. Characterized in that.

Preferably, the remote unit bypasses the at least one or more transmission signals, and then outputs the outputs to a port corresponding to the remote transmission area to transfer to another remote unit.

Preferably, the cable is a single coaxial cable.

In addition, the multi-input multiple output based in-building RF system according to the second aspect of the present invention for achieving the above object is provided through a service frequency band from each mobile communication terminal of the service allocation area in the in-building At least one UAM unit for converting at least one of the at least two transmission signals into an intermediate frequency and then outputting a cable connected with the unconverted transmission signal of the service frequency band; transmission of the service frequency band provided from the UAM unit At least one remote unit for converting a signal into an intermediate frequency different from a transmission signal provided by being converted from the UAM unit, and then outputting the signal to the base station transmission path together with the transmission signal converted and provided from the UAM unit; At least one transmission signal provided from the remote unit It characterized in that it comprises an in-building RF hub for converting the frequency of the band to be transmitted to the base station.

Preferably, the UAM unit is characterized in that for converting the transmission signal provided through the antenna preset as the frequency conversion target to an intermediate frequency.

Preferably, the cable is a single coaxial cable.

In addition, the multi-input multi-output based in-building RF system according to the third aspect of the present invention for achieving the above object, distinguish whether the frequency for the at least two or more transmission signals provided from the base station and the corresponding transmission signal To convert the frequencies so as to be discriminated from each other and transmit them to a cable in the in-building, or convert at least two or more transmission signals from the respective mobile communication terminal devices in the service allocation area in the in-building to the frequency of the base station band and transmit them to the base station. An in-building RF hub unit, which receives at least two transmission signals provided from the base station through the cable and outputs them to a port corresponding to the service allocation area and to a port corresponding to a remote transmission area; The at least two transmission signals provided from a communication terminal device At least one remote unit for transmitting to the building RF hub unit and at least two or more transmission signals provided from the base station from the port corresponding to the service allocation area receives the output frequency to form an antenna directed to the service allocation area At least one UAM unit for converting at least one of at least two transmission signals provided from the respective mobile communication terminal devices to an intermediate frequency and outputting the untransformed transmission signal of the service frequency band to the remote unit It is characterized by including.

Preferably, the remote unit converts at least one transmission signal of the at least one transmission signal into a service frequency for providing the service allocation area and outputs it to a port corresponding to the service allocation area.

Preferably, the UAM unit bypasses a transmission signal converted to a service frequency among the at least two transmission signals provided from a port corresponding to the service allocation region and radiates it to the service allocation region through a corresponding antenna. It is done.

Preferably, the UAM unit converts a transmission signal unconverted into a service frequency among the at least two or more transmission signals provided from a port corresponding to the service allocation area to a service frequency and radiates it to the service allocation area through a corresponding antenna. Characterized in that.

Preferably, the remote unit bypasses the at least one or more transmission signals, and then outputs the outputs to a port corresponding to the remote transmission area to transfer to another remote unit.

Preferably, the cable is a single coaxial cable.

In addition, the UDC amplifier module according to the fourth aspect of the present invention for achieving the above object, at least two or more transmission signals provided from the base station via the in-building transmission path based on the in-building RF system for mobile communication services Bypassing the transmission signal that is previously converted to the service frequency and converts the transmission signal unconverted to the service frequency to the service frequency, or provided through the service frequency band from each mobile communication terminal of the service allocation area in the in-building A frequency conversion / bypass unit for converting at least one of the at least two transmission signals into an intermediate frequency and then transmitting the unconverted service frequency band to the in-building transmission path and at least provided from the base station Provided by outputting two or more transmission signals at a service frequency Oh it characterized by including radiation in the service area assigned to, or the communication from each mobile terminal unit antenna for receiving at least two or more transmission signals of a service frequency band portion.

Preferably, the UDC amplifier module is characterized in that it further comprises an FSK modem for performing communication with the in-building RF hub supporting the mobile communication service between the base station and the in-building.

In addition, the multi-input multiple output based in-building RF method according to the fifth aspect of the present invention for achieving the above object, (A) the step of distinguishing whether the frequency is equal to at least two or more transmission signals provided from the base station, (B) converting frequencies between identical transmission signals so as to be discriminated from each other and transmitting them to a cable in an in-building; (c) transmitting the at least two transmission signals to a service allocation area through a remote that is a branch point of the cable; Outputting to a port and outputting to a port corresponding to a remote transmission area formed by another remote; and (d) outputting the at least two transmission signals provided from a port corresponding to the service allocation area at a service frequency. And radiating through an antenna that is directed to the service allocation area.

Preferably, the step (b) is characterized in that the cable is a single coaxial cable.

Preferably, the step (c) converts at least one transmission signal of the at least one transmission signal into a service frequency for providing the service allocation area and outputs the service frequency to a port corresponding to the service allocation area. do.

Preferably, the step (d) converts a transmission signal unconverted into a service frequency among the at least two transmission signals provided from a port corresponding to the service allocation area to a service frequency to allocate the service through a corresponding antenna. It is characterized in that the radiation to the area.

In addition, the multi-input multi-output based in-building RF method according to the sixth aspect of the present invention for achieving the above object, (a) the service frequency band from each mobile communication terminal of the service allocation area in the in-building Receiving at least two transmission signals, (b) converting at least one of at least two transmission signals of the service frequency band to an intermediate frequency and outputting the same to a cable connected with the untransformed transmission signal of the service frequency band (C) converting the transmission signal of the unconverted service frequency band through the remote which is the branch point of the cable into an intermediate frequency which is different from the transmission signal converted and transmitted in step (b), and then (b) (C) outputting a cable of a base station transmission path together with the transmitted signal transmitted in step (d) and (d) the base station transmission path Converts the transmission signal supplied from the cable to the frequency band of the base station is characterized in that it comprises the step of transmitting to the base station.

Preferably, the cable is characterized in that it is a single coaxial cable.

Accordingly, the present invention implements a mobile communication service in an in-building area based on a multi-input multi-output service without additionally constructing a cable of multiple lines, thereby providing an in-building RF provided with a single single cable. There is an advantage in implementing a mobile communication service in an in-building area that supports multiple input multiple outputs without additional cable construction for the system.

Hereinafter, a preferred embodiment of a multi-input multi-output based in-building RF system according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of an in-building RF system based on a multiple input multiple output according to an embodiment of the present invention. As shown by way of example only in FIG. 1, a multi-input, multi-output based in-building RF system is capable of incorporating at least two or more transmission signals provided from a base station 100 through signal conversion without passing through corresponding multiple cables. The base station may be transmitted to a corresponding mobile communication terminal 500 located in a service allocation area within a building or through signal conversion without transmitting a plurality of cables corresponding to at least two transmission signals generated from each mobile communication terminal 500. In order to deliver to 100, the in-building includes an in-building RF hub portion 200, at least one remote portion 300, and at least one UAM portion 400.

Here, the at least two or more transmission signals provided from the base station 100 or each of the mobile communication terminal devices 500 will be described in detail below as two first transmission signals and second transmission signals having the same frequency.

First, when the first transmission signal and the second transmission signal of the same frequency is provided from the base station 100, the in-building RF hub unit 200 provides the first transmission signal and the second transmission signal from the base station 100 If it is determined that the frequencies are the same and then the same frequency is determined, the frequency conversion is performed so that the frequencies between the two transmission signals are not the same, and the first transmission signal and the second transmission signal formed after the conversion are performed in-building. It is sent out by the cable inside. The cable in the in-building is preferably a single coaxial cable.

In order to perform the frequency conversion between the two transmission signals so that the frequencies are not the same, it is preferable to perform frequency conversion in consideration of the loss factor of the hand in the cable, and to convert it to a low frequency of about 100 MHz.

In addition, performing the frequency conversion between the two transmission signals so that the frequencies are not the same may convert both the first transmission signal and the second transmission signal so that the frequencies are not the same. It is more efficient to convert only one of the second transmission signals so that the frequencies do not coincide with each other.

The at least one remote unit 300 is a single coaxial cable, that is, a B cable connected to a port corresponding to a predetermined service allocation area by receiving a first transmission signal and a second transmission signal which have been subjected to frequency conversion through an A cable. In addition to the output, it is output by a C cable connected to a port corresponding to a remote transmission area formed by another remote unit.

After converting any one of the first transmission signal and the second transmission signal to be transmitted to the B cable to the service frequency, the remaining transmission signal without frequency conversion is amplified without restriction on the signal transmission, Each will be output.

At least two UAM (Up down converter Amp Module) units connected to the cable B receive the unconverted transmission signal and the unconverted transmission signal from the remote unit 300 after receiving the transmission signal converted into the service frequency. It converts the frequency and radiates it into the service allocation area through the corresponding antenna.

On the other hand, when the first transmission signal and the second transmission signal of the same frequency is provided from each mobile communication terminal device 500 in the service allocation area, at least one UAM unit is the first transmission signal and the second transmission signal of the service frequency band After converting any one of the intermediate frequency is output to the B cable is connected with the transmission signal of the unconverted service frequency band is transmitted to the remote unit 300.

Various methods may be applied to setting any one of the first transmission signal and the second transmission signal of the service frequency band. The transmission signal provided through the designated antenna after storing any one antenna in this manner It is possible to implement to convert to an intermediate frequency.

The remote unit 300 receiving the transmission signal converted into the intermediate frequency and the transmission signal of the unconverted service frequency band through the B cable has already received the transmission signal of the unconverted service frequency band from the UAM unit 400. After the frequency conversion is converted to an intermediate frequency that is different from the intermediate frequency of the provided transmission signal, both transmission signals are transferred to the in-building RF hub unit 200 through the A cable.

Accordingly, the in-building RF hub unit 200 converts both transmission signals provided from the remote unit 300 to the frequency of the base station 100 band and transmits them to the base station 100.

FIG. 2 is a configuration diagram of the UDC amplifier module shown in FIG. 1. As shown by way of example only in FIG. 2, the UDC amplifier module corresponding to the UAM unit 400 converts the first transmission signal and the second transmission signal provided from the base station 100 through the A cable and the B cable. After receiving through the process, the transmission signal that is already converted into the service frequency from the remote unit 300 is bypassed and the transmission signal that is not converted into the service frequency is converted into the service frequency or each of the service allocation area in the in-building. When the first transmission signal and the second transmission signal of the service frequency band are provided from the mobile communication terminal device 500, any one of the first transmission signal and the second transmission signal of the service frequency band is converted into an intermediate frequency and then unconverted. A frequency conversion / bypass unit 410 for outputting the B cable together with the transmitted signal of the service frequency band, and a first power provided from the base station 100. The transmission call and the second transmission signal are provided to be output at the service frequency and radiated to the service allocation area, or the first transmission signal and the second transmission signal of the service frequency band from each mobile communication terminal device 500 in the service allocation area. Antenna unit 420 for receiving.

The UDC amplifier module further includes an FSK modem 430 for communicating with the in-building RF hub unit 200 to transmit an operating state in the module to the in-building RF hub unit 200.

3 is a conceptual diagram illustrating an operation process of an in-building RF system based on a multi-input multi-output shown in FIG. 1 based on a frequency flow. As shown only as an example in FIG. 3, since the frequency of the transmission signal provided from the base station 100 is 125 MHz in the case of the WiBro system, the base station 100 has a first transmission signal having a frequency of 125 MHz and 125 MHz. The second transmission signal having a frequency of 2 is transmitted to the in-building RF hub unit 200, and the in-building RF hub unit 200 transmits the first transmission without performing frequency conversion on the second transmission signal. The signal is converted into IF @ Tx1, which is distinguished from the second transmission signal, and transferred to the remote unit 300.

The remote unit 300 converts the IF @ Tx1 into a service frequency of 2.3 GHz without performing frequency conversion on the second transmission signal, and then transfers both transmission signals to the UAM unit 400, and thus, the UAM unit ( 400 converts the second transmission signal that has not been converted into the service frequency to the service frequency to radiate through each corresponding antenna.

Meanwhile, the UAM unit 400 which receives the first transmission signal and the second transmission signal of the service frequency band from each mobile communication terminal device 500 in the service allocation area performs frequency conversion for the second transmission signal to perform an intermediate frequency. After forming at 75MHz, and transmits to the remote unit 300 together with the first transmission signal of the service frequency band.

The remote unit 300 converts the first transmission signal of the service frequency band into an intermediate frequency, that is, IF @ Rx1, which is distinct from the second transmission signal, which is an intermediate frequency of 75 MHz, without performing a frequency conversion of 75 MHz. The signal is transferred to the in-building RF hub unit 200. The in-building RF hub unit 200 converts the first transmission signal IF @ Rx1 to 75 MHz, which is a frequency of the base station 100 band, and then 75 MHz. Both transmission signals having a frequency of about will be transmitted to the base station 100.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below. I can understand that you can.

In addition, the present invention is to implement a mobile communication service in an in-building area based on a multi-input multi-output service without the need to additionally construct a cable of a number of lines, the possibility of commercialization or sales is sufficient. But it is an invention that is industrially applicable because it is practically evident.

1 is a block diagram of an in-building RF system based on multiple input multiple outputs according to an embodiment of the present invention;

2 is a configuration diagram of the UDC amplifier module shown in FIG.

3 is a conceptual diagram illustrating an operation process of an in-building RF system based on a multi-input multi-output shown in FIG. 1 based on a frequency flow.

<Description of Symbols for Main Parts of Drawings>

100: base station 200: in-building RF hub unit

300: remote portion 400: UAM portion

410: frequency conversion / bypass unit 420: antenna unit

430: FSK modem 500: mobile communication terminal device

Claims (24)

In-building RF system for mobile communication service, An in-building RF hub for discriminating whether the frequencies are the same for at least two transmission signals provided from the base station, converting the frequencies between the corresponding transmission signals to be discriminated from each other, and transmitting the same to each other in a cable in the in-building; At least one remote unit for outputting the at least two transmission signals provided through the cable to a port corresponding to a service allocation area and to a port corresponding to a remote transmission area; And And receiving at least two transmission signals from a port corresponding to the service allocation area, outputting at a service frequency, and including at least one UAM unit for radiating through an antenna directed to the service allocation area. Multi-output based in-building RF system. The method of claim 1, wherein the in-building RF hub portion A multi-input multiple output based in-building RF system, characterized in that for setting the frequency band for conversion based on the line loss rate in the cable. The method of claim 1, wherein the remote unit A multi-input multiple output based in-converter, converting at least one transmission signal among the at least one transmission signal into a service frequency for providing the service allocation region and outputting the service frequency to a port corresponding to the service allocation region; Building RF system. The method of claim 1, wherein the UAM portion The multi-input multi-output base of the at least two transmission signals provided from the port corresponding to the service allocation area bypasses the transmission signal converted to the service frequency and radiates to the service allocation area through a corresponding antenna. In-building RF system. The method of claim 1 or 4, wherein the UAM portion is Multiple input, characterized in that for converting the transmission signal unconverted to the service frequency of the at least two or more transmission signals provided from the port corresponding to the service allocation area to the service frequency and radiating to the service allocation area through a corresponding antenna Multi-output based in-building RF system. The method of claim 1, wherein the remote unit And bypassing the at least one transmission signal, outputting the signal to a port corresponding to the remote transmission area, and transmitting the same to another remote unit. The method of claim 1, wherein the cable Multi-input multi-output based in-building RF system, characterized in that a single coaxial cable. In-building RF system for mobile communication service, Converts at least one of the at least two transmission signals provided through the service frequency band from each mobile communication terminal in the service allocation area in the in-building into an intermediate frequency, and then connects the cable with the transmission signal of the unconverted service frequency band. At least one UAM unit for outputting; The transmission signal of the service frequency band provided from the UAM unit is converted into an intermediate frequency different from the transmission signal provided by being converted from the UAM unit, and then converted into a base station transmission path together with the transmission signal converted and provided from the UAM unit. At least one remote unit for outputting via a cable; And And a multi-input multi-output based in-building RF system for converting at least one transmission signal provided from the remote unit into a frequency of a base station band and transmitting the same to a base station. The method of claim 8, wherein the UAM portion A multi-input multi-output based in-building RF system, characterized in that for converting a transmission signal provided through a predetermined antenna as a frequency conversion target to an intermediate frequency. The method of claim 8, wherein the cable Multi-input multi-output based in-building RF system, characterized in that a single coaxial cable. In-building RF system for mobile communication service, Distinguish the frequency of at least two transmission signals provided from the base station and convert the frequencies between the corresponding transmission signals to be differentiated from each other and transmit them to the cable in the in-building, or each mobile communication terminal in the service allocation area in the in-building An in-building RF hub unit for converting at least two transmission signals from a device into a frequency of a base station band and transmitting the same to the base station; Receive at least two or more transmission signals provided from the base station through the cable and output to the port corresponding to the service allocation area and the port corresponding to the remote transmission area, or at least provided from each mobile communication terminal device At least one remote unit for transmitting at least two transmission signals to the in-building RF hub unit; And Receive at least two or more transmission signals provided from the base station from a port corresponding to the service allocation area and output them at a service frequency to radiate them through an antenna pointing to the service allocation area, or provide them from the respective mobile communication terminal devices. And converting at least one of the at least two transmission signals into an intermediate frequency and then outputting the remote unit together with the transmission signal of the unconverted service frequency band to the remote unit. In-building RF system. The method of claim 11, wherein the remote unit In-building based on multiple input multiple outputs, wherein at least one transmission signal of the at least one transmission signal is converted into a service frequency for providing the service allocation area and output to a port corresponding to the service allocation area. RF system. The method of claim 11, wherein the UAM portion The multi-input multi-output base of the at least two transmission signals provided from the port corresponding to the service allocation area bypasses the transmission signal converted to the service frequency and radiates to the service allocation area through a corresponding antenna. In-building RF system. The method of claim 11 or 13, wherein the UAM portion is Among the at least two transmission signals provided from the port corresponding to the service allocation area, the untransformed transmission signal into a service frequency is converted into a service frequency and radiated to the service allocation area through a corresponding antenna In-building RF system based on input multiple outputs. The method of claim 11, wherein the remote unit And bypassing the at least one transmission signal, outputting the signal to a port corresponding to the remote transmission area, and transmitting the same to another remote unit. The method of claim 11, wherein the cable Multi-input multi-output based in-building RF system, characterized in that a single coaxial cable. Based on the in-building RF system for the mobile communication service, the at least two transmission signals provided from the base station through the in-building transmission path are converted to the service frequency and bypassed and transmitted to the service frequency. After converting a transmission signal to a service frequency or converting at least one of at least two transmission signals provided through a service frequency band from each mobile communication terminal of the service allocation area in the in-building to an intermediate frequency and then unconverted service frequency A frequency conversion / bypass unit for transmitting the in-building transmission path together with a transmission signal of a band; And An antenna unit for receiving at least two transmission signals provided from the base station to be output at a service frequency to radiate to the service allocation area or to receive at least two transmission signals of a service frequency band from each mobile communication terminal device. UDC amplifier module comprising a. 18. The method of claim 17, wherein the UDC amplifier module And an FSK modem for communicating with an in-building RF hub supporting a mobile communication service between the base station and the in-building. (A) distinguishing whether the frequency is the same in at least two transmission signals provided from the base station; (B) converting frequencies between the same transmission signals so as to be discriminated from each other and transmitting them to a cable in the in-building; (C) outputting the at least two transmission signals to a port corresponding to a service allocation area through a remote which is a branch point of the cable and to a port corresponding to a remote transmission area formed by another remote; And And (d) outputting the at least two transmission signals provided from a port corresponding to the service allocation area at a service frequency and radiating them through an antenna that is directed to the service allocation area. Output-based in-building RF method. 20. The method of claim 19, wherein step (b) The multi-input multiple output based in-building RF method, characterized in that the cable is a single coaxial cable. 20. The method of claim 19, wherein the (c) step In-building based on multiple input multiple outputs, wherein at least one transmission signal of the at least one transmission signal is converted into a service frequency for providing the service allocation area and output to a port corresponding to the service allocation area. RF method. The method of claim 21, wherein the step (d) Multiple input, characterized in that for converting the transmission signal unconverted to the service frequency of the at least two or more transmission signals provided from the port corresponding to the service allocation area to the service frequency and radiating to the service allocation area through a corresponding antenna Multi-output based in-building RF method. (A) receiving at least two transmission signals of a service frequency band from each mobile communication terminal of the service allocation area in the in-building; (B) converting at least one of the at least two transmission signals of the service frequency band to an intermediate frequency and outputting the same to a cable connected with the unconverted transmission signal of the service frequency band; (C) step (b) after converting the transmission signal of the unconverted service frequency band through a remote which is a branch point of the cable to an intermediate frequency which is different from the transmission signal converted and transmitted in step (b); Outputting the cable of the base station transmission path together with the transmitted transmission signal converted in the; And (D) converting the transmission signals provided from the cable of the base station transmission path to the frequency of the base station band and transmitting them to the base station, characterized in that the multi-input multiple output based in-building RF method. The method of claim 19, wherein the cable A multi-input multi-output based in-building RF method characterized in that it is a single coaxial cable.

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