JP2013026894A - Modem and antenna control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a modem that can be used for both a BS modem and an antenna modem, and to provide an antenna control system.SOLUTION: The modem comprises: an AISG connectors 4a and 4b of which respective pin terminals for inputting and outputting a control signal and a power supply signal are electrically connected with each other; a modem circuit 5 that modulates the control signal input from the AISG connector 4a to generate and output the modulation signal, or demodulates the modulation signal into the control signal to be output to the AISG connector 4b; a combining and separating circuit 6 that combines the modulation signal and the power supply signal to generate and output an AISG signal, or separates the AISG signal into the modulation signal and the power supply signal to be output to the modem circuit 5 and the AISG connector 4b; and a bias T circuit 7 that superimposes the AISG signal on a feed signal to generate a superimposed signal and output the generated signal via an RF connector 3b or separates the superimposed signal into the AISG signal and the feed signal to be output to the combining and separating circuit 6 and the RF connector 3a.

Description

  The present invention relates to a modem and an antenna control system used in an antenna control system for controlling an antenna in conformity with the AISG (Antenna Interface Standards Group) standard.

  In mobile radio base stations, antenna tilt control can generally be performed by remote control. Initially, each manufacturer used a unique method as an antenna control method. However, in recent LTE (Long Term Evolution) radio base stations and the like, antenna control is often performed according to the AISG standard. The AISG standard is a standard standardized to ensure basic interoperability of antennas (see, for example, Patent Document 1).

  Usually, an AISG device (AISG terminal equipment) such as an antenna of a radio base station and a RET (Remote Electrical Tilt) unit that controls the antenna is arranged at a high position such as an upper part of a steel tower or a rooftop of a building. On the other hand, a radio that feeds power to an antenna and a control device (AISG control device) that controls an AISG device are generally arranged at a low position such as a lower part of a steel tower. Here, the control device transmits a control signal (RS485 standard signal) to the AISG device, controls the AISG device to control the antenna, and supplies power to the AISG device.

  The antenna and the radio are connected by a feed line (RF feed line) made of a coaxial cable, and the AISG device and the control device are connected by a control cable (AISG control cable) conforming to the AISG standard. For example, the antenna and the AISG are connected. When the device is arranged at the upper part of the steel tower and the radio device and the control device are arranged at the lower part of the steel tower, two cables of the feeder line and the control cable are laid from the upper part to the lower part of the steel tower.

  However, for example, in a steel tower as high as several tens of meters, it is very troublesome to lay cables from the upper part to the lower part of the steel tower, and the cost for the construction also increases. In order to solve this problem, the AISG standard defines a method called a coaxial interface or a modem option (hereinafter referred to as a coaxial interface method).

  As shown in FIG. 6, in the antenna control system 61 using the coaxial interface method, two modems called a BS modem 13 and an antenna modem 14 are provided in the middle of the feed line 12 that connects the antenna 10 and the radio 11. The BS modem 13 and the antenna modem 14 are used to transmit a control signal and a power signal for the AISG device 17 via the feeder line 12.

  The BS modem 13 is provided in the vicinity of the wireless device 11 (for example, the lower part of the steel tower), and a control device (AISG control device) 16 is connected via a control cable 15. The antenna modem 14 is provided in the vicinity of the antenna 10 (for example, at the top of the steel tower), and an AISG device 17 is connected via the control cable 15.

  As shown in FIG. 7, the BS modem 13 modulates a control signal (RS485A, RS485B) input from the control device 16 via the input AISG connector 21 by the modem (modem circuit) 22 to generate a modulated signal. Then, the modulation signal and the power signal input from the control device 16 are combined by the combining circuit 23, and the combined signal (referred to as AISG signal) is output to the bias T circuit (Bias Tee) 24. The bias T circuit 24 is configured by combining a DC blocking capacitor (capacitance element) and an AC blocking inductor (inductive element). The bias T circuit 24 receives the AISG signal input from the synthesis circuit 23 from the wireless device 11 as an input side RF. The signal is superimposed on the power supply signal (RF signal) input via the connector 25 and output from the output side RF connector 26 to the power supply line 12 on the antenna 10 side.

  As shown in FIG. 8, the antenna modem 14 inputs a power feeding signal (a power feeding signal on which an AISG signal is superimposed) input from the BS modem 13 via the input side RF connector 31 to the bias T circuit 32, and the bias T circuit. At 32, the AISG signal is separated from the feed signal. The separated feed signal is output from the output-side RF connector 33 to the feed line 12 on the antenna 10 side. The AISG signal separated by the bias T circuit 32 is further separated into a modulation signal and a power supply signal by the separation circuit 34. The separated modulation signal is demodulated by the modem (modem circuit) 35 and returned to the control signal. The demodulated control signal and the power signal separated by the separation circuit 34 are output to the AISG device 17 via the output AISG connector 36.

  In general, the modem 22 of the BS modem 13 and the modem 35 of the antenna modem 14 are of the same configuration. As shown in FIG. 9, the modems 22 and 35 modulate a control signal (RS485 standard signal) input to the RS485 interface 91 by a modulation circuit 92 to generate a modulated signal, and directionally couple the generated modulated signals. The modulation signal input to the directional coupler 93 is demodulated by the demodulation circuit 94, returned to the control signal, and output from the RS485 interface 91 to the outside. Has been. The power supply circuit 95 of the modems 22 and 35 uses the power supplied from the control device 16 to convert the input power supply voltage to the voltage for the modems 22 and 35, and the RS485 interface 91, the modulation circuit 92, and the demodulation circuit. It is comprised so that it may output to 94.

  The combining circuit 23 of the BS modem 13 and the separation circuit 34 of the antenna modem 14 are both configured using a low-pass filter or the like, and have the same configuration. Furthermore, the bias T circuit 24 of the BS modem 13 and the bias T circuit 32 of the antenna modem 14 are the same.

  By adopting such a coaxial interface method, it is only necessary to lay the feeder line 12 from the upper part to the lower part of the tower, and the total cost of the antenna control system including the construction cost can be greatly suppressed. Become.

Special table 2010-519844 gazette

  As described above, the internal circuits of the BS modem 13 and the antenna modem 14 are almost the same, but at present, the BS modem 13 and the antenna modem 14 are handled as different devices.

  The present inventor considered that if there is a modem that can be used for both the BS modem 13 and the antenna modem 14, it is possible to reduce the cost by reducing the components of the system and to realize an antenna control system having a simple configuration. .

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a modem and an antenna control system that can be used for both a BS modem and an antenna modem.

  The present invention was devised to achieve the above object, and is used in an antenna control system for controlling an antenna in accordance with the AISG standard, and two RF connectors to which the antenna feed line is connected; In accordance with the AISG standard, pin terminals for inputting / outputting control signals and pin terminals for inputting / outputting power signals are respectively electrically connected to the input side AISG connector and the output side AISG connector. It is electrically connected to a pin terminal for inputting / outputting a control signal, and modulates the control signal input from the input side AISG connector to generate and output a modulation signal, or demodulates the input modulation signal. A modem circuit that returns the control signal and outputs it to the output side AISG connector, and is electrically connected to the input / output unit of the modulation signal of the modem circuit In addition, it is electrically connected to a pin terminal for inputting / outputting power signals of both the AISG connectors, and the modulation signal input from the modem circuit and the power signal input from the input side AISG connector are combined to form an AISG. A synthesizing / separating circuit that generates and outputs a signal, or separates an input AISG signal into a modulation signal and a power supply signal and outputs them to the modem circuit and the output side AISG connector; The AISG signal is electrically connected to the input / output unit of the AISG signal, and is electrically connected to both the RF connectors, and the AISG signal input from the combining / separating circuit is supplied to the power supply signal input from one of the RF connectors. Superposed signal is generated and output from the other RF connector, or input from the other RF connector A bias T circuitry separates the tatami signal to AISG signal and the power supply signal output to the RF connector of the synthesis and separation circuit and one, a modem equipped with.

  The input-side AISG connector is a male connector with the pin terminal exposed to the outside, and an excessive short circuit occurs in the input-side AISG connector when a short circuit occurs at the pin terminal that inputs and outputs the power signal of the input-side AISG connector You may further provide the short circuit current suppression means which suppresses that an electric current flows.

  The short circuit current suppressing means may comprise a diode provided to prevent the short circuit current.

  The short circuit current suppressing means may comprise a current limiting element.

  From the power signal input via the input side AISG connector or the power signal output from the combining / separating circuit, a power signal of another voltage specified by the AISG standard is generated to generate the output side AISG connector. A DC / DC converter that outputs to the output may be further provided.

  The present invention also provides an AISG device that controls the antenna in accordance with the AISG standard, a control signal transmitted to the AISG device, the AISG device that controls the antenna, and the AISG device. It is provided in the middle of a feeder that connects a power supply signal of one voltage specified by the AISG standard to the antenna and a radio that feeds power to the antenna, and is connected to the controller. The control signal input from the control device is modulated to generate a modulation signal, and the modulation signal and the power supply signal input from the control device are superimposed on the power supply signal input from the wireless device. A BS modem that outputs to the feeder line on the antenna side, and is provided in the middle of the feeder line on the antenna side with respect to the BS modem. SG device is connected, and the modulation signal and the power signal are separated from the power feeding signal inputted from the BS modem, and the modulation signal is demodulated and returned to the control signal, and the control signal and the power signal are separated to the AISG device. An antenna control system including an antenna modem that outputs a later feed signal to the feed line on the antenna side, wherein the modem is used for at least one of the BS modem and the antenna modem.

  ADVANTAGE OF THE INVENTION According to this invention, the modem and antenna control system which can be used for both BS modem and an antenna modem can be provided.

(A) is a schematic block diagram of the antenna control system using the modem which concerns on one embodiment of this invention, (b) is a schematic block diagram of a modem. It is a cross-sectional view which shows an example of the control cable used for the antenna control system of FIG. (A), (b) is a schematic block diagram which shows the modification of the modem of FIG.1 (b). It is a schematic block diagram which shows the modification of the modem of FIG.1 (b). It is a schematic block diagram when the modem of FIG.1 (b) is built in the housing | casing same as an AISG device. It is a schematic block diagram of the conventional antenna control system. It is a schematic block diagram of the conventional BS modem used for the conventional antenna control system of FIG. It is a schematic block diagram of the antenna modem used for the conventional antenna control system of FIG. It is a schematic block diagram of the modem (modem circuit) used for BS modem of FIG. 7, and the antenna modem of FIG.

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

  FIG. 1 is a schematic configuration diagram of an antenna control system using a modem according to the present embodiment, and (b) is a schematic configuration diagram of the modem.

  As shown in FIG. 1, the antenna control system 1 transmits a control signal to the AISG device 17 that controls the antenna 10 in accordance with the AISG standard, and controls the AISG device 17 to control the antenna 10. A control device 16 that performs control and transmits a power signal of one voltage specified by the AISG standard to the AISG device 17 and a power supply line 12 that connects the antenna 10 and the radio 11 that supplies power to the antenna 10. A BS modem 13 of the present invention provided in the middle and an antenna modem 14 provided in the middle of the feeder line 12 closer to the antenna 10 than the BS modem 13 are provided.

  Here, as an example, a case will be described in which the control device 16 supplies a 10-30 V power source that is an essential connection, and the AISG device 17 uses a 10-30 V power source.

  The BS modem 13 modulates a control signal input from the control device 16 to generate a modulation signal, and a signal (referred to as an AISG signal) obtained by synthesizing the modulation signal and the power supply signal input from the control device 16 is wirelessly transmitted. A signal (referred to as a superimposed signal) superimposed on a power feed signal (RF signal) input from the device 11 is output to the power feed line 12 on the antenna 10 side.

  The antenna modem 14 separates the AISG signal from the superimposed signal input from the BS modem 13, separates the AISG signal into a modulation signal and a power signal, demodulates the modulation signal, and returns it to the control signal. The signal is output to the AISG device 17 and the separated feed signal is output to the feed line 12 on the antenna 10 side.

  The antenna control system 1 according to the present embodiment uses the modem 2 of the present invention as at least one of the BS modem 13 and the antenna modem 14. Here, a case where the modem 2 of the present invention is used for both the BS modem 13 and the antenna modem 14 will be described, but either one may be used.

  Although details of the modem 2 will be described later, the modem 2 includes two RF connectors 3a and 3b to which the feeder 12 of the antenna 10 is connected, an input side AISG connector (male connector) 4a compliant with the AISG standard, and an output side. An AISG connector (female connector) 4b is provided. Both RF connectors 3a and 3b are general coaxial cable connectors, and both AISG connectors 4a and 4b are general connectors conforming to the AISG standard.

  The modem 2 used as the BS modem 13 is provided in the vicinity of the wireless device 11 (for example, the lower part of the steel tower), and a control device 16 is connected via a control cable 15. The modem 2 used as the antenna modem 14 is provided in the vicinity of the antenna 10 (for example, at the top of the steel tower), and an AISG device 17 is connected via the control cable 15.

  As shown in FIG. 2, the control cable 15 includes two control signal lines 44 that transmit control signals and three power supply lines 45 for supplying power. A drain wire 46 is vertically attached to the two control signal lines 44, and a shield tape (metal tape) is provided around the two control signal lines 44 and the drain wire 46 so as to surround them collectively. 47 is provided.

  The three power supply lines 45 include two power supply lines 45a and 45c set with different voltages and a DC return power supply line 45b. Here, a case is shown in which a -48V line 45a for transmitting -48V power and a 10-30V line 45c for transmitting 10-30V power are provided.

  The three power supply lines 45 are arranged around the two control signal lines 44 (around the shield tape 47) together with the intervening 48, and the shield tape 49, the braided shield 50, and the sheath 51 so as to surround them all together. Are provided sequentially.

  The control cable 15 in FIG. 2 is shown as an example only, and the control cable 15 is not limited to the configuration in FIG. For example, in the antenna control system 1 according to the present embodiment, only the 10 to 30 V power supply is used and the −48 V line 45 a is not used. .

  Returning to FIG. 1A, a male connector 15a and a female connector 15b are provided at both ends of the control cable 15, respectively. The control device 16 is provided with an output connector (female connector) 16a, and the AISG device 17 is provided with an input connector (male connector) 17a. These connectors 15a, 15b, 16a, and 17a are general connectors (AISG connectors) conforming to the AISG standard. Although not shown, the AISG device 17 is provided with an output connector (female connector) so that a plurality of AISG devices 17 can be connected in a daisy chain.

  By connecting the male connector 15a of the control cable 15 to the output connector 16a of the control device 16 and connecting the female connector 15b of the control cable 15 to the input side AISG connector 4a of the modem 2 used as the BS modem 13, the control device 16 And the modem 2 used as the BS modem 13 are connected via a control cable 15. A power supply line 12 extending from the wireless device 11 is connected to one RF connector 3a of the modem 2 used as the BS modem 13, whereby the wireless device 11 and the modem 2 used as the BS modem 13 connect the power supply line 12. Connected through.

  Further, the male connector 15a of the control cable 15 is connected to the output side AISG connector 4b of the modem 2 used as the antenna modem 14, and the female connector 15b of the control cable 15 is connected to the input connector 17a of the AISG device 17, thereby The modem 2 used as the modem 14 and the AISG device 17 are connected via the control cable 15. In addition, a power supply line 12 extending to the antenna 10 is connected to one RF connector 3a of the modem 2 used as the antenna modem 14, so that the modem 2 and the antenna 10 used as the antenna modem 14 are connected via the power supply line 12. Connected.

  Furthermore, by connecting both ends of the feeder line 12 to the other RF connector 3b of the modem 2 used as the BS modem 13 and the modem 2 used as the antenna modem 14, both modems 2 are connected via the feeder line 12. The

  Next, the modem 2 according to the present embodiment will be described.

  As shown in FIG. 1B, the modem 2 includes two RF connectors 3a and 3b, an input side AISG connector 4a and an output side AISG connector 4b, a modem circuit 5, a synthesis / separation circuit 6, and a bias T. The circuit 7 is mainly provided.

  The input side AISG connector 4a and the output side AISG connector 4b are the third and fifth pin terminals (RS485A, RS485B) for inputting / outputting control signals, and the pin terminals (here, 10-30V power supply) for inputting / outputting power signals. No. 6 pin terminals for inputting / outputting are electrically connected to each other by internal wiring. Although not shown in the drawings, the AISG connectors 4a and 4b are also electrically connected to the 7th pin terminals for DC return by internal wiring. Note that pin terminals for inputting / outputting power signals not used (+ 12V power supply and −48V power supply) may or may not be connected between the two AISG connectors 4a and 4b. Note that the pin terminal numbers are defined in the AISG standard.

  The modem circuit 5 modulates the control signal input from the input side AISG connector 4a to generate a modulation signal and outputs it to the synthesis / separation circuit 6, or demodulates the modulation signal input from the synthesis / separation circuit 6 Then, the control signal is returned to the output side AISG connector 4b, which is the same as described with reference to FIG. The control signal input / output unit (RS485 interface) of the modem circuit 5 is electrically connected to the third and fifth pin terminals (RS485A and RS485B) for inputting and outputting the control signals of both AISG connectors 4a and 4b through internal wiring. The modulation signal input / output unit is electrically connected to the modulation signal input / output unit of the synthesis / separation circuit 6 by an internal wiring.

  The synthesizing / separating circuit 6 generates an AISG signal by synthesizing the modulation signal input from the modem circuit 5 and the power supply signal input from the input side AISG connector 4a, and outputs the generated AISG signal to the bias T circuit 7. Alternatively, the AISG signal input from the bias T circuit 7 is separated into a modulation signal and a power supply signal and output to the modem circuit 5 and the output side AISG connector 4b, respectively. The power supply signal input / output section of the combining / separating circuit 6 is electrically connected to the 6th pin terminal (10 to 30V DC) for inputting / outputting the power supply signals of both AISG connectors 4a and 4b. The output unit is electrically connected to the input / output unit of the AISG signal of the bias T circuit 7.

  The bias T circuit 7 generates a superimposed signal by superimposing the AISG signal input from the combining / separating circuit 6 on the power supply signal input from one RF connector 3a and outputs the superimposed signal from the other RF connector 3b, or The superimposed signal input from the other RF connector 3b is separated into an AISG signal and a power feeding signal and output to the synthesizing / separating circuit 6 and one RF connector 3a, respectively. The input / output portion of the power supply signal of the bias T circuit 7 is electrically connected to one RF connector 3a, and the input / output portion of the superimposed signal is electrically connected to the other RF connector 3b.

  By the way, the input side AISG connector 4a is a male connector (plug) with a pin terminal exposed to the outside. When the modem 2 is used as the antenna modem 14, nothing is connected to the input side AISG connector 4 a and it is left open. At this time, a power signal is input because dust adheres to the exposed pin terminals. It is conceivable that a short circuit occurs at the output pin terminal, or the operator touches the pin terminal and gets an electric shock. Therefore, as a countermeasure, in the present embodiment, it is possible to prevent an excessive short-circuit current from flowing through the input-side AISG connector 4a when a short-circuit occurs at a pin terminal that inputs and outputs the power signal of the input-side AISG connector 4a. Short circuit current suppression means 8 is further provided.

  Here, a diode 8 a is used as the short-circuit current suppressing means 8. The diode 8a is provided to prevent a short circuit current. In this embodiment, a branch is made from an internal wiring extending from the input / output portion of the power supply signal of the synthesis / separation circuit 6 to the 6th pin terminal (10 to 30 V DC) of the output side AISG connector 4b, and the input side AISG connector 4a In the internal wiring extending to the 6th pin terminal (10-30V DC), the anode electrode is on the input side AISG connector 4a side (illustrated upper side) and the cathode electrode is on the output side AISG connector 4b side (illustrated lower side) A diode 8a was provided.

  When the power supply used is a 10-30V power supply or a + 12V power supply, that is, a positive power supply, the direction of the diode 8a may be the direction shown in FIG. 1B, but the power supply used is a -48V power supply, That is, in the case of a negative power supply, the direction of the short-circuit current that flows at the time of a short circuit is reversed, so that the direction of the diode 8a is reversed, that is, the anode electrode is on the output side AISG connector 4b side, as shown in FIG. It is necessary that the cathode electrode is on the input side AISG connector 4a side (upper side in the figure).

  Further, as shown in FIG. 3B, a current limiting element 8 b can be used as the short circuit current suppressing means 8. As the current limiting element 8b, for example, a polymer PTC (Positive Temperature Coefficient) thermistor or the like can be used.

  Returning to FIG. 1, the operation of the modem 2 will be described.

  First, the operation when the modem 2 is used as the BS modem 13 will be described.

  When the modem 2 is used as the BS modem 13, the radio unit 11 is connected to the RF connector 3a, the antenna modem 14 (here, the modem 2 used as the antenna modem 14) is connected to the RF connector 3b, and the input side AISG connector 4a. The control device 16 is connected to. The output side AISG connector 4b may be left open, or the AISG device 17 may be daisy chain connected to the output side AISG connector 4b.

  The control signal input from the control device 16 via the input side AISG connector 4 a is converted into a modulation signal by the modem circuit 5 and output to the synthesis / separation circuit 6. The synthesizing / separating circuit 6 generates an AISG signal by combining the modulation signal and the power supply signal, and outputs the AISG signal to the bias T circuit 7. The bias T circuit 7 superimposes the AISG signal on the power feeding signal input from the wireless device 11 via the RF connector 3 a to generate a superimposed signal, and outputs the superimposed signal from the RF connector 3 b to the antenna modem 14.

  Next, the operation when the modem 2 is used as the antenna modem 14 will be described.

  When the modem 2 is used as the antenna modem 14, the antenna 10 is used for the RF connector 3a, the BS modem 13 (here, the modem 2 used as the BS modem 13) is used for the RF connector 3b, and the AISG device 17 is used for the output side AISG connector 4b. Will be connected. The input side AISG connector 4a is left open. At this time, even if a short-circuit occurs at the pin terminal of the input side AISG connector 4a that is left open, the short-circuit current is blocked by the short-circuit current suppressing means 8, thus preventing a short-circuit accident or an electric shock accident. it can.

  The superimposed signal input from the BS modem 13 via the RF connector 3b is separated into an AISG signal and a feeding signal by the bias T circuit 7, the AISG signal is sent to the combining / separating circuit 6, and the feeding signal is sent from the RF connector 3a to the antenna 10. Is output. The synthesizing / separating circuit 6 separates the AISG signal into the modulation signal and the power signal, and outputs the modulation signal to the modem circuit 5 and the power signal from the output side AISG connector 4b to the AISG device 17. The modem circuit 5 demodulates the modulated signal, returns it to the control signal, and outputs it to the AISG device 17 from the output side AISG connector 4b.

  As described above, according to the present invention, the modem 2 that can be used for both the BS modem 13 and the antenna modem 14 can be realized. Conventionally, the BS modem 13 and the antenna modem 14 have been handled as separate products. However, according to the present invention, both the BS modem 13 and the antenna modem 14 can be supported by one product, and as a result, the system Therefore, the antenna control system 1 having a simple configuration can be realized at a low cost.

  In the present embodiment, since the modem 2 includes the short-circuit current suppressing means 8, the input-side AISG connector 4 a is overloaded when a short circuit occurs at the pin terminal that inputs and outputs the power signal of the input-side AISG connector 4 a. Can prevent a short circuit current from flowing, and can prevent a short circuit accident or an electric shock accident.

  The present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the spirit of the present invention.

  For example, although not mentioned in the above embodiment, a surge protection circuit 9 is provided in the vicinity of both AISG connectors 4a and 4b as in the modem 41 shown in FIG. The modem 2 may be configured to protect an internal circuit (such as the modem circuit 5).

  Further, like a modem 42 shown in FIG. 4B, a power signal input via the input side AISG connector 4a or a power signal output from the combining / separating circuit 6 (here, 10 to 30 V power source) It further includes a DC / DC converter 18 that generates a power supply signal (+12 V power supply in this case) defined by the AISG standard and outputs it to the output side AISG connector 4b, and is different from the power supply voltage supplied by the control device 16. The AISG device 17 that uses the power supply voltage may be used.

  Here, although the case where the thing which produces | generates and outputs + 12V power supply from 10-30V power supply as DC / DC converter 18 is shown, it does not restrict to this, The power supply voltage which the control apparatus 16 outputs, and the output side Depending on the power supply voltage to be output from the AISG connector 4b (that is, the power supply voltage used by the AISG device 17 connected to the output side AISG connector 4b), a -48V power supply is generated and output from the 10-30V power supply, or -48V Of course, it is possible to generate and output a 10 to 30 V power source or a +12 V power source from a power source, or to generate and output a 10 to 30 V power source or a −48 V power source from a +12 V power source.

  Furthermore, two power supply signals (for example, a -48V power supply and a + 12V power supply) having different voltages defined by the AISG standard and different voltages from the input power supply signal (for example, 10-30V power supply) are generated. It is also possible to provide a DC / DC converter 18 and output all three types of power supplies defined by the AISG standard.

  In the modem 42 in FIG. 4B, the output of the DC / DC converter 18 is also connected to the input side AISG connector 4a. When a short circuit occurs at the pin terminal for inputting / outputting the power signal of the AISG connector 4a, an excessive short circuit current is prevented from flowing into the input side AISG connector 4a. If the output of the DC / DC converter 18 is not connected to the input side AISG connector 4a, the diode 19 can be omitted.

  Furthermore, as shown in FIG. 5, the modem 2 of the present invention may be mounted in the same housing as the AISG device 17 such as RET. In this case, the power supply circuit of the modem circuit 5 and the power supply circuit of the AISG device 17 can be shared. By configuring in this way, it is possible to realize the AISG device 17 that can handle both the case where the control signal and the power signal are input by the control cable 15 and the case where the control signal and the power signal are input by the feeder 12. Become. Of course, it is possible to incorporate the modem 2 of the present invention in the same housing as the distributor (AISG signal distributor) and arrester.

  In the above embodiment, the case where the radio device 11 and the control device 16 are separate has been described. However, a control device with a wireless function in which the radio device 11 and the control device 16 are integrated is used. It may be.

DESCRIPTION OF SYMBOLS 1 Antenna control system 2 Modem 3a, 3b RF connector 4a Input side AISG connector 4b Output side AISG connector 5 Modem circuit 6 Combining / separating circuit 7 Bias T circuit 8 Short-circuit current suppression means 8a Diode 10 Antenna 11 Radio equipment 12 Feed line 13 BS Modem 14 Antenna modem 15 Control cable 16 Control device 17 AISG device

Claims (6)

Used in antenna control systems that control antennas in accordance with AISG standards,
Two RF connectors to which the antenna feeder is connected;
In accordance with the AISG standard, the input side AISG connector and the output side AISG connector in which pin terminals for inputting / outputting control signals and pin terminals for inputting / outputting power signals are electrically connected,
Electrically connected to pin terminals for inputting / outputting control signals of both AISG connectors and modulating the control signal input from the input side AISG connector to generate a modulated signal and outputting it, or input modulation A modem circuit for demodulating the signal, returning it to the control signal and outputting it to the output side AISG connector;
The modulation signal input / output unit of the modem circuit is electrically connected to the pin terminal for inputting / outputting the power signal of the both AISG connectors, and the modulation signal input from the modem circuit The power supply signal input from the input side AISG connector is combined to generate and output an AISG signal, or the input AISG signal is separated into a modulation signal and a power supply signal to separate the modem circuit and the output side AISG connector. A synthesis / separation circuit that outputs to
The synthesis / separation circuit is electrically connected to the input / output unit of the AISG signal, and is electrically connected to both the RF connectors. The feeding signal input from one of the RF connectors is supplied from the synthesis / separation circuit. A superimposed signal is generated by superimposing the input AISG signal and output from the other RF connector, or the superimposed signal input from the other RF connector is separated into an AISG signal and a feed signal and the combined signal is generated. A bias T circuit that outputs to the separation circuit and one of the RF connectors;
A modem characterized by comprising: The input side AISG connector is a male connector with the pin terminal exposed to the outside,
The apparatus further comprises short-circuit current suppressing means for suppressing an excessive short-circuit current from flowing through the input-side AISG connector when a short circuit occurs at a pin terminal for inputting / outputting a power signal of the input-side AISG connector. The listed modem. The modem according to claim 2, wherein the short-circuit current suppressing unit includes a diode provided to prevent the short-circuit current. The modem according to claim 2, wherein the short-circuit current suppressing unit includes a current limiting element. From the power signal input via the input side AISG connector or the power signal output from the combining / separating circuit, a power signal of another voltage specified by the AISG standard is generated to generate the output side AISG connector. The modem according to any one of claims 1 to 4, further comprising a DC / DC converter that outputs to a power source. An AISG device that controls the antenna in accordance with the AISG standard;
A control device that transmits a control signal to the AISG device, controls the AISG device to control the antenna, and transmits a power signal of one voltage defined in the AISG standard to the AISG device;
Provided in the middle of a feed line connecting the antenna and a radio that feeds the antenna, the control device is connected, and modulates a control signal input from the control device to generate a modulation signal, A BS modem that superimposes the modulation signal and the power supply signal input from the control device on the power supply signal input from the radio, and outputs the signal to the power supply line on the antenna side,
It is provided in the middle of the power supply line on the antenna side of the BS modem, and the AISG device is connected to separate the modulation signal and the power signal from the power supply signal input from the BS modem. An antenna modem that demodulates and returns to the control signal, outputs the control signal and the power signal to the AISG device, and outputs the separated feed signal to the feed line on the antenna side;
In an antenna control system with
An antenna control system using the modem according to any one of claims 1 to 5 as at least one of the BS modem and the antenna modem.