KR100645356B1 - Method and RF Repeater System for Enhancing Communication Quality in Shadow Area by Using CCTV Facility - Google Patents

Abstract

The present invention relates to an RF relay system and method for improving the call quality of the radio shadow area using CCTV equipment.

The present invention provides an RF relay system for improving an RF environment of a radio shadow area by using a CCTV facility installed in a radio shadow area. The present invention provides a base station RF signal transmitted from a base station or a terminal RF signal transmitted from a mobile communication terminal. A donor antenna for transmitting to a base station; A remote unit for filtering and amplifying a base station RF signal received from a donor antenna, or for filtering and amplifying a terminal RF signal received from a mobile communication terminal; Among the base station RF signals filtered and amplified by the remote unit, a signal of a frequency band interfering with the video signal of the CCTV equipment is interrupted, and an impedance matching function for outputting the maximum power of the base station RF signal, the terminal RF signal and the video signal of the CCTV equipment is performed. Performing a first divider & filter & matching (DFM); A second DFM which blocks a signal of a frequency band interfering with a video signal of a CCTV facility among a terminal RF signal, and performs an impedance matching function for outputting maximum power of a base station RF signal, a terminal RF signal, and a video signal of a CCTV facility; A CCTV cable transmitting the base station RF signal output from the first DFM and the terminal RF signal output from the second DFM; And a remote antenna for transmitting a base station RF signal to a mobile communication terminal, or receiving a terminal RF signal and transmitting the received RF signal to a remote unit. do.

According to the present invention, by installing an RF repeater using a cable of the CCTV already installed in the radio shadow area, by improving the RF environment in the radio shadow area for simple equipment construction and low cost to improve the call quality of the mobile communication terminal It can be effective.

Radio shade area, RF repeater, CCTV cable, RF environment improvement

Description

RF relay system and method for improving the call quality in the radio shadow area using the CCTV system {Method and RF Repeater System for Enhancing Communication Quality in Shadow Area by Using CCTV Facility}

1 is a block diagram schematically illustrating a configuration network of a CDMA-2000;

FIG. 2 is a block diagram schematically illustrating a configuration of an RF repeater using a frequency division duplexing (FDD) method. FIG.

3 is a view showing the configuration of the RF relay system for improving the call quality in the elevator by using CCTV equipment according to a preferred embodiment of the present invention,

4 is a view showing a state in which video signal of CCTV is interfered by a signal amplified from a remote unit in the absence of Divider & Filter & Matching (DFM) according to the present invention;

5 is a view showing a state in which the video signal of the CCTV is not interfered by the signal amplified from the remote unit when there is a DFM according to the present invention;

6 is a view schematically showing the internal structure of a DFM according to an embodiment of the present invention;

FIG. 7 is a flowchart illustrating a process of RF relaying an RF signal transmitted from a base station according to an embodiment of the present invention to a mobile communication terminal in the radio shadow area by using a CCTV facility already installed in the radio shadow area.

FIG. 8 is a flowchart illustrating a process of RF relaying an RF signal transmitted from a mobile communication terminal to a base station by using a CCTV facility pre-installed in a radio shadow area according to an embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

300 donor antenna 302 remote portion

304, 308: DFM 306: CCTV Cable

310: remote antenna 312: CCTV camera

314: CCTV monitor 602: low frequency cut filter

604: impedance matching circuit 606: divider

The present invention relates to an RF relay system and method for improving the call quality of the radio shadow area using CCTV equipment. More specifically, by connecting the remote antenna of the conventional RF repeater to the remote part of the RF repeater using a cable of CCTV already installed in the radio shadow area, RF signals between the base station and the mobile communication terminal in the radio shadow area. By relaying, the present invention relates to a system and a method for improving the call quality of a mobile communication terminal by improving the RF environment in a radio wave shadow area such as an elevator.

 The mobile communication system has been developed through the first generation analog AMPS (Advanced Mobile Phone System), the second generation Cellular (Cellurar) / Personal Communication Service (PCS), and the third generation high speed data. International Mobile Telecommunication-2000 (IMT-2000) has been developed.

The IMT-2000 enables roaming using the same frequency band (2 GHz) around the world. There are two types of European asynchronous CDMA and North American synchronous CDMA. There are two types of CDMA mobile communication systems in North America, CDMAOne and CDMA-2000. CDMAOne is for an entire system including IS-95, which is a wireless section protocol, and CDMA-2000 is a whole system based on IS-2000, a wireless section protocol. Means.

1 is a block diagram schematically illustrating a configuration network of a CDMA-2000.

A base station transceiver system (BTS) 102 performs a function of wirelessly matching the mobile communication terminal 100 to provide a mobile communication service to a mobile subscriber. The interface between the base station and the mobile terminal follows the IS-2000 standard.

A base station controller (BSC) 104 connects a voice call and a line data call between the BTS 102 and the MSC 108 and a packet data call between the BTS 102 and the DCN 120. do. It performs vocoding function for voice calls and operates, maintains and repairs the base station.

Hereinafter, the BTS 102 and the BSC 104 are collectively referred to as a base station system (BSS) 106.

Mobile Switching Center (MSC) 108 is a system that performs a switching function in a CDMA-2000 network, and performs a function of connecting a mobile subscriber in a network with a subscriber of another network. It is also connected with various additional systems to provide additional services.

Public Switched Telephone Network (PSTN) 110 is a wired public telephone network provided by a general wired telecommunications company, and is configured to allow telephone calls between subscribers by connecting a telephone line to a telephone exchange facility.

Data core network (DCN) 120 is a separate network required to provide packet data communication services such as Internet communications to mobile subscribers, and provides PDSN 112, HA 114, and AAA (Authorization) to provide mobility to subscribers. , Authentication and Accounting) 116, router 118, and the like. In the case of the PDSN 112, the BSC 104 and the DCN 120 perform a function of matching.

The Packet Data Serving Node (PDSN) 112 is an interface between the DCN 120 and an external Internet network, which routes / tunnels packets directed to a mobile node (MN) and manages location information data of the MN. Do this.

Home Agent (HA) 114 is a mobile IP (Internet Protocol) and initial registration, IP routing and route optimization, mobile subscriber's address management and mobile information management, tunneling and reverse to provide connection with various servers of the Internet It performs functions such as tunneling.

Authentication Authorization Accounting (AAA) 116 performs a role of subscriber server in mobile IP, performs key distribution and billing processing resource management functions related to authentication and authorization, and router 118. ) Is used to connect the PDSN 112 to the Internet.

In general, a mobile communication system divides a mobile communication service area into a plurality of cells by using a frequency reuse concept and the like to expand coverage of a mobile communication network, and moves near the center of each cell. Wireless base stations are installed to handle communication services. Here, the radius of the cell is determined according to the signal strength of the region or the traffic amount of data. In other words, the cell radius is reduced in urban areas with high traffic volume, and the cell radius is increased in non-city areas with relatively low traffic volume. Do not exceed the.

Despite efforts to support better mobile communication services by appropriately adjusting the cell radius according to the frequency reuse concept and the traffic volume, in the urban area, radio waves generally exist in underground, apartments or apartment buildings, tunnels, etc. There are radio wave shadow areas that are difficult to reach. Installing a number of new wireless base stations to address the radio shadows in these radio shadow areas is not only economically difficult due to facility costs, installation costs, and maintenance costs, but can also be undesirable in cell design. There will be.

As a solution to this, a mobile communication service can be provided using a repeater in such a radio shadow area. The repeater amplifies the base station signal and transmits it to the radio wave shadow area so that the signal of the base station can reach the radio wave shadow area, and amplifies the signal of the mobile terminal so that the signal of the mobile communication terminal located in the radio wave shadow area can reach the base station. And filtration is sent to the base station to solve the problem of radio wave shading.

Here, the repeater is a method of transmitting a signal by amplifying the entire frequency band of the carrier and transmitting the signal by separating the frequency allocation (FA), and as a method for extending coverage, it is mainly to the ground repeater and underground and in-building repeater. The most common type of repeater is the RF repeater.

FIG. 2 is a block diagram schematically illustrating a configuration of an RF repeater using a frequency division duplexing (FDD) method.

The RF repeater is largely comprised of a donor antenna 200, a remote unit 202, and a remote antenna 204, and the remote unit 202 includes a band pass filter (BPF) 206, duplexers 208 and 216, and an LNA ( Low Noise Amplifier (210) and (218), Attenuator (212, 220), HPA (High Power Amplifier) (214, 222).

Briefly describing the operation principle of the RF repeater, the RF signal transmitted from the base station is transferred to the BPF 206 through the donor antenna 200 of the RF repeater. The BPF 210 passes only signals of frequency bands used for transmitting signals between the base station and the mobile communication terminal, removes signal components of other frequency bands, and transfers the signal components to the duplexer 208.

The duplexer 208 transfers the input RF signal to the LNA 210, which reduces the noise component of the RF signal, amplifies the signal component, and delivers the signal component to the attenuator 212. The attenuator 212 adjusts the signal level of the RF signal and delivers it to the HPA 214, which amplifies the effective output for transmitting the RF signal to the duplexer 216. The duplexer 216 radiates an RF signal to the mobile communication terminal through the remote antenna 204.

On the contrary, when the RF signal is received from the mobile communication terminal through the remote antenna 204, the duplexer 216 transfers the received RF signal to the LNA 218. LNA 218 reduces the noise component of the RF signal, amplifies the signal component, and passes it to attenuator 220. The attenuator 220 adjusts the signal level of the RF signal and delivers it to the HPA 222. The HPA 222 amplifies the effective output for transmitting the RF signal to the duplexer 208. The duplexer 208 transfers the received RF signal to the BPF 206, and the BPF 206 passes only signals of the transmission frequency band, removes signal components of other frequency bands, and removes the RF signal through the donor antenna 200. Radiates to the base station.

Such RF repeater is mainly suitable for the service in small buildings, and the low cost of the facility is widely used to solve the radio shadow area of the underground space or the narrow space in the building.

By the way, the interior of the elevator, which is a representative example of the radio wave shadow area in a building, has been limited to the improvement of the RF environment using a repeater. In other words, in order to install an RF repeater in an elevator, a new incoming proximity line must be newly installed, which is a technical and cost-related construction problem, and there is a problem that institutional restrictions are placed on the installation of the repeater even under the Fire Safety Act. In addition, a rooftop radial repeater is introduced to improve the RF environment inside the elevator, which is still poor in the high-rise buildings with five or more floors, and the installation cost is not low. That is, the conventional repeater does not solve the radio shadow area in the elevator at low cost effectively.

After all, despite the efforts to solve the radio shadow area through various repeaters, the interior of the elevator has a problem in that it does not effectively improve the RF environment at low cost and provides a good call quality to many mobile terminal users. will be.

In order to solve this problem, the present invention, in order to improve the radio shadow area, in particular the RF environment inside the elevator at low cost as a simple device without the installation of new incoming proximity line, the remote antenna in the RF repeater to the existing elevator facility By connecting to the remote part of the RF repeater using the installed CCTV cable to relay the RF signal between the base station and the mobile communication terminal in the radio shadow area, the RF in the radio shadow area such as inside the elevator at simple facility construction and low cost It is an object of the present invention to provide a system and method for improving the call quality of a mobile communication terminal by improving the environment.

According to a first object of the present invention for achieving the above object, in the RF relay system for improving the RF environment of the radio wave shadow area by using the CCTV equipment installed in the radio wave shadow area, receiving the base station RF signal transmitted from the base station Or a donor antenna for transmitting a terminal RF signal transmitted from a mobile communication terminal to a base station; A remote unit for filtering and amplifying a base station RF signal received from a donor antenna, or for filtering and amplifying a terminal RF signal received from a mobile communication terminal; Among the base station RF signals filtered and amplified by the remote unit, a signal of a frequency band interfering with the video signal of the CCTV equipment is interrupted, and impedance matching is performed for maximum power output of the base station RF signal, the terminal RF signal, and the video signal of the CCTV equipment. A first divider & filter & matching (DFM) for performing a function; A second DFM which blocks a signal of a frequency band interfering with a video signal of a CCTV facility among a terminal RF signal, and performs an impedance matching function for outputting maximum power of a base station RF signal, a terminal RF signal, and a video signal of a CCTV facility; A CCTV cable transmitting the base station RF signal output from the first DFM and the terminal RF signal output from the second DFM; And a remote antenna for transmitting a base station RF signal to a mobile communication terminal, or receiving a terminal RF signal and transmitting the received RF signal to a remote unit. do.

According to a second object of the present invention, in the device that the RF signal is transmitted through a cable together with the video signal of the CCTV without causing interference with the video signal of the CCTV, causing interference with the video signal of the CCTV among the RF signal A low frequency cut filter for blocking a frequency band signal; And an impedance matching circuit for outputting the maximum power of the RF signal and the video signal of the CCTV to provide interference and filter & matching (DFM) for preventing the RF signal from interfering with the video signal of the CCTV.

According to a third object of the present invention, there is provided a method of relaying an RF signal transmitted from a base station to a mobile communication terminal in the radio shadow area by using a CCTV facility installed in the radio shadow area. Receiving by the donor antenna; (b) filtering and amplifying the RF signal received at the donor antenna at the remote unit; (c) blocking a signal of a frequency band interfering with the video signal of the CCTV among the RF signals filtered and amplified by the remote unit and matching an impedance for maximum power output of the RF signal and the video signal of the CCTV; (d) transmitting an RF signal in which a signal of a frequency band interfering with a video signal of CCTV is cut off to a remote antenna through a cable of CCTV; And (e) provides an RF relay method for improving the call quality of the radio wave shadow area using a CCTV facility comprising the step of transmitting the RF signal transmitted to the mobile communication terminal to the remote antenna.

According to a fourth object of the present invention, there is provided a method for relaying an RF signal transmitted from a mobile communication terminal to a base station using CCTV equipment installed in a radio wave shadow area, wherein (a) the remote antenna transmits an RF signal transmitted from the mobile communication terminal. Receiving; (b) blocking a signal of a frequency band interfering with the video signal of the CCTV among the RF signals received by the remote antenna, and matching impedance for maximum power output of the RF signal and the video signal of the CCTV; (c) transmitting an RF signal from which a signal of a frequency band interfering with a video signal of CCTV is cut off to a remote unit through a cable of CCTV; (d) filtering and amplifying the RF signal transmitted to the remote unit; And (e) transmitting the filtered and amplified RF signal from the remote unit to the base station through a donor antenna to improve the call quality of the radio wave shadow area using a CCTV facility. .

According to a fifth object of the present invention, a method of transmitting an RF signal together with a video signal of a CCTV through a single cable without causing interference to the video signal of the CCTV, (a) of the RF signal, the video signal of the CCTV Blocking signals in the frequency band causing interference; And (b) transmitting the RF signal in which a signal of a frequency band interfering with the video signal of the CCTV is cut off through a cable together with the video signal of the CCTV. Provides a way to transmit over a single cable with CCTV video signals without causing interference.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

3 is a view showing the configuration of the RF relay system for improving the call quality in the elevator by using a CCTV equipment according to a preferred embodiment of the present invention.

RF relay system according to a preferred embodiment of the present invention is a donor antenna 300, a remote unit 302, Divider & Filter & Matching (DFM) 304, 308, CCTV cable 306, remote antenna 310, etc. It has a configuration including.

The RF relay system according to the present invention basically comprises a donor antenna 300, a remote unit 302 and a remote antenna 310, and receives the RF signal transmitted from the base station at the donor antenna to filter and After amplifying and transmitting to a mobile communication terminal through a remote antenna or a RF signal transmitted from a mobile communication terminal by a remote antenna, filtered and amplified by a remote unit, and then transmitted to a base station through a donor antenna and Basically, RF signals are relayed on a similar principle. However, the remote unit 302 is not installed inside the elevator due to the fire safety law, and the remote antenna 310 and the remote unit 302 are connected by using the existing CCTV cable 306 installed without a new additional line facility. It is to relay the RF signal transmission and reception between the base station and the mobile terminal, the RF relay system is operated in a configuration including a signal control device called DFM (304, 308) so as not to affect the operation of the existing CCTV.

The RF signal transmitted from the base station is transmitted to the remote unit 302 through the donor antenna 300. As described above, the remote unit 302 passes only signals of frequency bands used for transmitting signals between the base station and the mobile communication terminal, removes signal components of other frequency bands, and then reduces noise components of the input RF signal. By amplifying the signal component, the signal level of the RF signal is adjusted to amplify the effective output for transmitting the RF signal wirelessly, and then transferred to the DFM 304.

The DFM 304 collides with the CCTV video signal transmitted from the CCTV camera 312 through the CCTV cable 306 by the amplified signal from the remote unit 302 and distorts the video signal of the CCTV input to the CCTV monitor 314. It performs a function to prevent the phenomenon.

In general, the frequency used in CCTV is 5 ~ 65 KHz low frequency, the frequency used in the mobile communication system is a high frequency of 800 Mhz, the range of frequencies used in CCTV and mobile communication system is quite different from each other. However, in the case of transmitting signals through a CCTV cable as shown in FIG. 3, radio signals in CCTV and mobile communication systems that have a significantly different range of use frequencies may cause interference between the two signals. That is, some low frequency noises mixed among radio signals in a mobile communication system may cause noise floors that affect low frequency signals (5 to 65 KHz) used in CCTV. will be.

Accordingly, the DFM 304 according to the present invention blocks the low frequency signal (for example, 300 KHz or less) that affects the video signal of the CCTV among the signals amplified from the remote unit 302, thereby reducing the remote unit 302. By amplifying the signal and the video signal of the CCTV is to prevent the noise floor phenomenon caused by sharing one CCTV cable 306.

In addition, the DFM 304 according to the present invention filters and matches the amplified signal from the remote unit 302 as described above, and then inputs the CCTV cable 306 without being input to the CCTV monitor 314. It performs a function of dividing a signal to be transmitted to the remote antenna 310 through.

As such, the RF signal from the base station filtered and matched through the DFM 304 is transmitted to the DFM 308 using the CCTV cable 306 as a path, and then separated from the path from the DFM 308 to the CCTV camera 312. And transmitted to the remote antenna 310. Thereafter, the RF signal is radiated to the mobile communication terminal inside the elevator through the remote antenna 310.

On the contrary, when the RF signal is received from the mobile communication terminal through the remote antenna 310, the RF signal is filtered and matched in the DFM 308, and then transmitted to the DFM 304 by the CCTV cable 306 as a path. It is separated from the path from the DFM 304 to the CCTV monitor 314 and transmitted to the remote unit 302. Thereafter, the remote unit 302 transmits the filtered and amplified signal to the base station through the donor antenna 300.

That is, the RF relay system for improving the call quality in the elevator by using the CCTV equipment according to the preferred embodiment of the present invention, the portion shown in red in Figure 3, the conventional CCTV equipment, the donor antenna 300, the remote It is an RF relay system that can improve the RF environment in an elevator only by installing new materials of the unit 302, the DFMs 304 and 308, and the remote antenna 310.

4 and 5 are a view showing the presence or absence of distortion of the CCTV video signal when the signal amplified from the remote unit and the CCTV video signal is transmitted by sharing one CCTV cable, when there is no DFM according to the present invention to be.

4 is a view showing a state in which the video signal of the CCTV is interfered by a signal amplified from the remote unit when there is no DFM according to the present invention.

When the RF signal transmitted from the base station is amplified by the remote unit, the noise level also increases in all bands. Due to the noise level rise, low frequency (for example, 300 KHz or less) noise is generated, and as shown in the graph of FIG. 4, it interferes with the video signal of low frequency (for example, 15 KHz) CCTV to block the video signal of CCTV. Phenomenon occurs. That is, the video signal of the CCTV transmitted from the CCTV camera is blocked, so that no image appears on the CCTV monitor or the image is distorted.

5 is a view showing a state in which the video signal of the CCTV is not interfered by the signal amplified from the remote unit when there is a DFM according to the present invention.

When the RF signal transmitted from the base station is amplified by the remote unit, the noise level is also increased in all bands. However, in the DFM according to the present invention, a low frequency (eg 300 KHz or less) signal affecting the video signal of the low frequency (eg 15 KHz) CCTV is cut off as shown in the graph of FIG. The video signal of the CCTV is transmitted to the CCTV monitor without interference of the RF signal amplified by the remote unit, so that the CCTV does not distort the CCTV monitor and operates normally.

4 and 5 are views for explaining the function of the DFM in the process of transmitting the RF signal transmitted from the base station to the mobile communication terminal through the remote unit and CCTV cable, on the contrary, the RF signal transmitted from the mobile communication terminal is CCTV cable And the function of the DFM in the process of being delivered to the base station through the remote unit may be similarly described.

6 is a view schematically showing the internal structure of a DFM according to an embodiment of the present invention.

The DFM 600 according to the embodiment of the present invention has a configuration including a low frequency cutoff filter 602, an impedance matching circuit 604, a divider 606, and the like.

The low frequency cut-off filter 602 blocks the low frequency signal that affects the video signal of the CCTV among the RF signals transmitted from the remote antenna or the donor antenna, and the impedance matching circuit 604 uses the output signal of the remote or donor antenna and the CCTV signal. Match the impedance so that the video output signal is output at full power.

The divider 606 separates and combines the RF signal transmitted from the remote antenna or donor antenna and the video signal of CCTV.

7 is a flowchart illustrating a process of RF relaying an RF signal transmitted from a base station according to an exemplary embodiment of the present invention to a mobile communication terminal in the radio shadow area by using a CCTV facility installed in the radio shadow area.

When the donor antenna of the RF repeater receives the RF signal transmitted from the base station (S700), the RF signal is filtered and amplified by the remote unit of the RF repeater (S702). The process of filtering and amplifying the RF signal at the remote unit is as described above. Among the RF signals filtered and amplified by the remote part, the signal of a frequency band (for example, 300 KHz or less) that interferes with the video signal of the CCTV is blocked (S704), so that the RF signal is connected to an elevator through an existing cable of CCTV. After transmitting to the remote antenna in the shadowed area (S706), by transmitting the RF signal to the mobile communication terminal via the remote antenna (S708) it is relayed the RF signal from the base station to the mobile communication terminal in the radio shaded area.

FIG. 8 is a flowchart illustrating a process of RF relaying an RF signal transmitted from a mobile communication terminal to a base station by using a CCTV facility pre-installed in a radio shadow area according to an embodiment of the present invention.

When receiving an RF signal transmitted from the mobile communication terminal to the remote antenna in the shaded area (S800), by blocking the signal of the frequency band (for example 300 KHz or less) that interferes with the video signal of CCTV among the RF signal (S802) After transmitting the RF signal to the remote unit through the existing cable of the CCTV (S804), the RF signal is filtered and amplified in the remote unit of the RF repeater (S806). The process of filtering and amplifying the RF signal at the remote unit is as described above. Subsequently, by transmitting the filtered and amplified RF signal to the base station through the donor antenna (S808), the RF signal from the mobile communication terminal in the radio shadow area is relayed to the base station.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, according to the present invention, by connecting a remote antenna of a conventional RF repeater with a remote part of an RF repeater using a CCTV cable that is already installed in the radio shaded area, the base station and the mobile communication in the radio shaded area By relaying the RF signal between the terminals, there is an effect that can improve the call quality of the mobile communication terminal by improving the RF environment in the radio shadow area, such as inside the elevator.

In addition, since only a simple operation of connecting the DFM (Divider & Filter & Matching) according to the present invention to the existing cable of CCTV is required, it can be easily installed without any trace of construction at low cost. In particular, the elevator has an effect that can efficiently solve the problems in the installation of the incoming proximity line and the fire safety law.

Table 1 is a table showing the test results of the RF relay system for improving the call quality in the elevator by using the CCTV equipment according to an embodiment of the present invention.

According to the embodiment of the present invention, when the RF relay using the CCTV equipment, the call state in the elevator was unsatisfactory, the call quality was improved by the improvement of the RX level and Ec / Io.

In addition, when the conventional rooftop radial repeater is installed, poor communication occurred in a high floor of five or more floors, but according to the embodiment of the present invention, a good call state was stably provided in all floors even in a high floor, and the installation cost was also a rooftop. It cost 200,000 won less than a radial repeater.

On the other hand, according to the present invention, there is an effect that can improve the RF environment within the radio wave shadow area without the phenomenon that the screen of CCTV by the DFM according to the present invention.

9 is a view showing the components and the installation state of the RF relay system for improving the call quality of the radio wave shadow area using the CCTV equipment according to an embodiment of the present invention.

As shown in FIG. 9, the RF relay system according to the present invention has a structure in which a small DFM can be easily installed in a pre-installed CCTV cable, and a remote antenna (dome-type omni antenna) is also compact and used in space and exterior of an elevator. Can be installed without impact.

Claims (27)

In the RF relay system for improving the RF environment of the radio shade area by using CCTV equipment installed in the radio shade area, A donor antenna configured to receive a base station RF signal transmitted from a base station or to transmit a terminal RF signal transmitted from a mobile communication terminal to the base station; A remote unit for filtering and amplifying the base station RF signal received from the donor antenna or filtering and amplifying the terminal RF signal received from the mobile communication terminal; Blocking the signal of the frequency band that interferes with the video signal of the CCTV equipment of the base station RF signal filtered and amplified by the remote unit, and outputs the maximum power of the base station RF signal, the terminal RF signal and the video signal of the CCTV equipment A first divider & filter & matching (DFM) for performing an impedance matching function for the network; Blocking the signal of the frequency band that interferes with the video signal of the CCTV equipment of the terminal RF signal, and performs an impedance matching function for the maximum power output of the base station RF signal, the terminal RF signal and the video signal of the CCTV equipment Second DFM; A CCTV cable transmitting the base station RF signal output from the first DFM and the terminal RF signal output from the second DFM; And A remote antenna for transmitting the base station RF signal to the mobile communication terminal or receiving and transmitting the terminal RF signal to the remote unit; RF relay system for improving the call quality of the radio wave shaded area using the CCTV equipment, characterized in that it comprises a. The method of claim 1, The remote unit for filtering and amplifying the base station RF signal or the terminal RF signal operates in an FDD (Frequency Division Duplexing) method in which a duplexer is included. RF relay system. The method of claim 1, The frequency band of the base station RF signal or the terminal RF signal that interferes with the video signal of the CCTV equipment, which is blocked by the first DFM or the second DFM, is less than 300 KHz. RF relay system to improve local call quality. The method of claim 1, The CCTV equipment in the RF relay system, the RF relay system for improving the call quality of the radio wave shadow area using the CCTV equipment, characterized in that it further comprises a CCTV camera and a CCTV monitor connected to each other by the CCTV cable. . The method of claim 4, wherein The first DFM outputs the base station RF signal only to the remote antenna side without outputting to the CCTV monitor side, and outputs the terminal RF signal only to the remote unit side without outputting to the CCTV monitor side. RF relay system to improve the call quality in the radio shadow area by using. The method of claim 4, wherein The second DFM outputs the terminal RF signal only to the remote unit side without outputting the CCTV camera side, and outputs the base station RF signal only to the remote antenna side without outputting the CCTV camera side. RF relay system to improve the call quality in the radio shadow area by using. The method of claim 4, wherein The CCTV camera is an RF relay system for improving the call quality of the radio wave shadow area using CCTV equipment, characterized in that the use frequency is 5 KHz to 65 KHz. delete The method of claim 1, The radio shaded area is an RF relay system for improving the call quality of the radio shaded area using CCTV equipment, characterized in that the inside of the elevator, apartments, apartments and tunnels. An apparatus for transmitting an RF signal through a cable together with the video signal of the CCTV without interfering with the video signal of the CCTV, A low frequency cut-off filter which performs a function of blocking a signal of a frequency band causing interference with the video signal of the CCTV among the RF signals; And Impedance matching circuit for maximum power output of the RF signal and the video signal of the CCTV RF &lt; RTI ID = 0.0 &gt; FM &lt; / RTI &gt; to prevent the RF signal from interfering with the video signal of CCTV. The method of claim 10, The RF signal is a DFM so that the RF signal transmitted from the base station is an RF signal filtered and amplified by an RF repeater or an RF signal transmitted from a mobile communication terminal does not interfere with the video signal of the CCTV. The method of claim 10, The DFM further comprises a divider for separating and combining the RF signal and the video signal of the CCTV so that the RF signal does not interfere with the video signal of the CCTV. The method of claim 12, The divider is a DFM for separating the RF signal so that the RF signal is not output to the monitor side of the CCTV or the camera side of the CCTV so that the RF signal does not interfere with the video signal of the CCTV. delete The method of claim 10, The frequency band of the RF signal which is interrupted by the low-frequency cut filter, the interference of the video signal of the CCTV is characterized in that the RF signal is less than 300 KHz so that the RF signal does not interfere with the video signal of the CCTV. The method of claim 10, The video signal of the CCTV is a DFM so that the RF signal, characterized in that the use frequency is 5 KHz to 65 KHz does not interfere with the video signal of the CCTV. A method of relaying an RF signal transmitted from a base station to a mobile communication terminal in the radio shadow area by using a CCTV equipment installed in the radio shadow area, (a) a donor antenna receiving an RF signal transmitted from the base station; (b) filtering and amplifying the RF signal received at the donor antenna at a remote unit; (c) blocking a signal of a frequency band interfering with the video signal of the CCTV among the RF signals filtered and amplified by the remote unit, and matching an impedance for maximum power output of the RF signal and the video signal of the CCTV; Making; (d) transmitting the RF signal from which the signal of the frequency band which causes interference to the video signal of the CCTV is cut off to a remote antenna through a cable of the CCTV; And (e) transmitting the RF signal transmitted to the remote antenna to the mobile communication terminal RF relay method for improving the call quality of the radio shaded area by using a CCTV equipment comprising a. 18. The method of claim 17, wherein in step (c), The frequency band of the RF signal that interferes with the video signal of the CCTV is an RF relay method for improving the call quality of the radio wave shadow area using a CCTV facility, characterized in that less than 300 KHz. delete 18. The method of claim 17, wherein in step (d), The transmitting of the RF signal to the remote antenna through the cable of the CCTV, CCTV, characterized in that only transmitting to the remote antenna side without transmitting the RF signal to the monitor side of the CCTV or the camera side of the CCTV. RF relay method that improves the call quality in the radio shadow area using equipment. A method for relaying an RF signal transmitted from a mobile communication terminal to a base station using a CCTV facility installed in a radio wave shadow area, (a) receiving, by a remote antenna, an RF signal transmitted from the mobile communication terminal; (b) blocking a signal of a frequency band interfering with the video signal of the CCTV among the RF signals received by the remote antenna, and matching an impedance for maximum power output of the RF signal and the video signal of the CCTV; ; (c) transmitting the RF signal from which a signal of the frequency band which causes interference to the video signal of the CCTV is cut off to a remote unit through a cable of the CCTV; (d) filtering and amplifying the RF signal transmitted to the remote unit at the remote unit; And (e) transmitting the RF signal filtered and amplified by the remote unit to the base station through a donor antenna RF relay method for improving the call quality of the radio shaded area by using a CCTV equipment comprising a. The method of claim 21, wherein in step (b), The frequency band of the RF signal that interferes with the video signal of the CCTV is an RF relay method for improving the call quality of the radio wave shadow area using a CCTV facility, characterized in that less than 300 KHz. delete The method of claim 21, wherein in step (c), The transmitting of the RF signal to the remote unit through the cable of the CCTV, CCTV equipment, characterized in that for transmitting only to the remote antenna side, without transmitting the RF signal to the monitor side of the CCTV or the camera side of the CCTV. RF relay method to improve the call quality in the radio shadow area using A method of transmitting an RF signal together with the video signal of the CCTV via one cable without causing interference to the video signal of the CCTV, (a) blocking a signal of a frequency band causing interference with the video signal of the CCTV among the RF signals; And (b) transmitting the RF signal, in which the signal of the frequency band is interrupted to the video signal of the CCTV, through the cable together with the video signal of the CCTV; RF signal, characterized in that it comprises a method of transmitting via a single cable with the video signal of the CCTV without causing interference to the video signal of the CCTV. The method of claim 25, The RF signal is an RF signal transmitted from a base station is an RF signal filtered and amplified by an RF repeater or an RF signal transmitted from a mobile communication terminal. How to transmit over a single cable with a signal. The method of claim 25, wherein in step (a), The frequency band of the RF signal that interferes with the video signal of the CCTV is less than 300 KHz, characterized in that the RF signal is transmitted via a single cable together with the video signal of the CCTV without causing interference to the video signal of the CCTV .

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