JPH0636496B2 - Automatic measurement system for microwave antenna system characteristics for fixed communication - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an automatic measurement system of microwave antenna system characteristics for fixed communication.

[Conventional technology]

As a microwave antenna system used in a fixed microwave communication system for public communication, a plurality of bands such as 4 to 6G is used.
There is one that uses both horizontal polarized wave and vertical polarized wave of the same frequency with the same antenna for the purpose of effective use of frequency, which is shared in the Hz band.

In a communication system using such a microwave antenna system, in order to effectively separate and receive the signals between both the horizontal polarization and the vertical polarization, the antenna system of the own station is opposed to the antenna of the opposite station. In addition to adjusting the direction of the antenna itself, it is necessary to adjust the group demultiplexer installed in the waveguide system of the 4 to 6 GHz band shared antenna as the direction adjustment toward the system. , There are the following.

(1) Antenna-to-group demultiplexer opposition cross discrimination test After adjusting the direction of opposition to the antenna and adjusting the waveguide system of one station to the group demultiplexer, the waveguide of its own station to the antenna of the partner station In the test to confirm whether the system is electrically confronting, at a single frequency near the center of each frequency band of 4 to 6 GHz, the amount of leakage of radio waves output in horizontal polarization to vertical polarization. And, measure the amount of leakage of the radio wave output in the vertical polarization to the horizontal polarization.

(2) Group demultiplexer facing cross discrimination test A confirmation test in the section performed after the adjustment of the direction of the antenna facing, the adjustment of the waveguide system and the group demultiplexer of both stations,
The leakage amount of the radio wave output in the horizontal polarization to the vertical polarization and the leakage amount of the radio wave output in the vertical polarization to the horizontal polarization are 4 to 6
Measure every 1 MHz in each frequency band of GHz.

In addition, there are the following items (3) and (4) as the measurement items of the propagation path between the own station and the other station due to geographical conditions.

(3) Effective return loss measurement A test to measure the section condition due to fading of the relay section between the partner station and the own station in the band. 1 MHz for both horizontal and vertical polarization in the entire frequency band used. The effective return loss (U / D ratio) is measured for each.

(4) Measuring the amount of interference The amount of interference of radio waves output from other stations to the local station without emitting radio waves from the other station Is measured every 1 MHz.

As a measurement system of the above antenna system characteristics, conventionally, a transmitter is arranged on the transmitting station side, a receiver is arranged on the receiving station side, and while contacting by a telephone call by a subscriber telephone or a wireless transceiver, the above (1) to ( In the measurement of 3), the transmitter station and the receiver station each manually adjust the transmission and reception frequencies, and in the measurement of (4) above, disable the transmitter and manually adjust the receiver frequency. Methods of measuring are known.

In addition, as another conventional measurement system, an automatic sweep type transmitter is placed on the transmitting station side, and a microwave amplifier and spectrum analyzer are placed on the receiving station side. Meanwhile, in the above measurements (1) to (3), the measurement frequency from the transmitter is manually swept in an analog fashion to emit radio waves, and this is manually set by the microwave amplifier and spectrum analyzer of the receiving station. In the measurement of (4) above, there is known a method in which the transmitter is deactivated and the microwave amplifier and the spectrum analyzer of the receiving station are manually operated.

[Problems to be Solved by the Invention]

However, in the former former measurement system,
Since the measurement is manually performed while adjusting the measurement frequency, there is a problem that the measurement is troublesome and takes time. For example, the frequency bands used for public communication in the above 4 to 6 GHz band are 3600 MHz to 4200 MHz in the 4 GHz band, 4400 MHz to 5000 MHz in the 5 GHz band, and 5925 MHz to 6425 MHz in the 6 GHz band.
Therefore, even if the band is divided into two for transmission and reception for each band, in the measurement that requires adjustment of the measurement frequency for each 1 MHz, it is necessary to adjust the frequency more than 800 times in total.

Also, in the latter measurement system, since it is operated manually, there is also the problem that measurement is cumbersome and time-consuming, and in this case, an automatic sweep type transmitter or spectrum analyzer is used. However, there is a problem that the measuring equipment becomes expensive.

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to provide an automatic measurement system capable of simply and quickly measuring various characteristics of a microwave antenna system for fixed communication with an inexpensive measuring device. And

[Means and Actions for Solving the Problems]

To achieve the above object, in the present invention, in measuring the characteristics of a microwave antenna system between a transmitting station and a receiving station for fixed communication, the transmitting station receives microwaves via the microwave antenna system of the transmitting station. A microwave transmitter capable of transmitting at a predetermined frequency step and its control device are arranged, and the receiving station can receive a microwave at a predetermined frequency step through a microwave antenna system of the receiving station. A microwave receiver and an arithmetic and control unit thereof are arranged, and a telephone line is connected between the control unit on the transmitting station side and the arithmetic and control unit on the receiving station side. The transmission of microwaves from a microwave transmitter and the reception of microwaves by the microwave receiver, with the receiving station as a main station, the arithmetic and control unit and the transmitting station on the receiving station side. The control device on the side of the microwave antenna system between the transmitting station and the receiving station is controlled by the full-duplex communication system and the arithmetic and control unit controls the microwave based on the input electric field of the microwave received by the microwave receiver. Automatically measures the characteristics of.

〔Example〕

FIG. 1 is a system diagram showing an example of an automatic measurement system of microwave antenna system characteristics for fixed communication embodying the present invention. On the transmitting station side, the microwave transmitter 1, the control device 2,
The communication adapter 3 and the telephone 4 are arranged, and the microwave receiver 5, the arithmetic and control unit 6, the communication adapter 7 and the telephone 8 are arranged on the receiving station side.

The microwave transmitter 1 arranged on the transmitting station side is connected to an antenna system on the transmitting station side having a microwave antenna 11 and the control device 2, and the communication adapter 3 is connected to the control device 2 and the telephone 4. The microwave receiver 5 arranged on the receiving station side is connected to the antenna system on the receiving station side having the microwave antenna 12 and the arithmetic control unit 6, and the communication adapter 7 is connected to the arithmetic control unit 6 and the telephone set 8. do it,
The arithmetic control unit 6 on the receiving station side and the control unit 2 on the transmitting station side are connected via the communication adapter 7, the telephone line 13 and the communication adapter 3.

In this embodiment, as the microwave transmitter 1 and the microwave receiver 5, microwave transmitters / receivers whose transmission and reception can be selected by switching terminals are used, and a personal computer (personal computer) is used as the control device 2 and the arithmetic control device 6. To use.

FIG. 2 shows a concrete connection of the measuring equipment in this embodiment. The communication adapter 3 (7) is, for example, COMSTA.
R 2424AT / 5 (made by NEC) is used, which is connected to telephone 4 (8) and telephone line 13 via telephone line 15, and RS
Via a -232C connection cable 16
-Connect to the RS-232C terminal of 286LS STD (manufactured by EPSON).
This PC 17 has an expansion board (GP-IB) 18, such as PC-9
801-29n (manufactured by NEC) is connected and connected to the control terminal of the microwave transceiver 20 via the GP-IB connection cable 19.

Thus, in this embodiment, the receiving station is the main station,
Interface the GP-IB 18 to control the transmitter of the partner station (transmitting station) through full-duplex communication from the receiver of the own station through the personal computer communication (MNP method), and the microwave transceiver by the personal computer 17 of both stations. 20 is operated as a sweep signal generator on the transmitting station side and as a spectrum analyzer on the receiving station side to automatically measure various characteristics of the microwave antenna system.

FIG. 3 is a block diagram showing the configuration of an example of the microwave transceiver 20 shown in FIG. This microwave transceiver 20
Has a circuit section that constitutes a transmitter and a receiver, a control section 21 that controls the operation of this circuit section by a control signal from a personal computer, and a power supply section 22 that supplies power to each section. The vertically polarized input / output terminal 25-1 and the horizontally polarized input / output terminal 25-2 are connected to the switching terminal 27 via the coaxial switch 26 controlled by the control unit 21. The input / output terminal 25-1 and the input / output terminal 25-2 are
For each measurement frequency band, at the transmitting station and the receiving station, connect to the vertical polarization terminal and horizontal polarization terminal of the corresponding duplexer of the antenna system. However, since no radio wave is emitted from the transmitting station in the measurement of the amount of interference, the transmitter need not be connected to the antenna system in this measurement.

The switching terminal 27 is connected to the RF input terminal 28 when the microwave transceiver 20 is operated as a receiver, and
RF input signal is 4 to 6 GHz band band pass filter (BPF) 2
9 and the circulator 30 and then supplied to the mixer 31,
Here, the frequency is converted by being mixed with the local signal supplied from the first local oscillator 32 through the circulator 33 and the coaxial switch 34. The coaxial switch 34 supplies a local signal to the mixer 31 in the receiver,
In the transmitter, it is connected under the control of the control unit 21 so that the local signal is supplied to the TX output terminal 35.

The first local oscillator 32 is based on the output of the crystal oscillator 36, which produces a 100 MHz reference signal, at 3.
Outputs a signal of the required frequency (test frequency) in 1 MHz steps in the range of 6 GHz to 6.5 GHz, and the receiver has a frequency difference of 100 M with respect to the frequency of the RF input signal (test frequency).
The control unit 21 is controlled to output a local signal of Hz.

The output of the mixer 31 is supplied to a mixer 40 via an amplifier 37, a BPF 38 having a center frequency of 100 MHz and a bandwidth (BW) of 5 MHz and a variable attenuator 39, where a frequency of 121.4 supplied from a second local oscillator 41. Frequency conversion is performed by mixing with the local signal of MHz. The attenuation amount of the variable attenuator 39 is controlled by the control unit 21 in steps.

The output of mixer 40 is B with a center frequency of 21.4 MHz and a BW of 3 MHz.
It is supplied to a logarithmic amplifier 46 via a PF42, an intermediate frequency amplifier 43, a gain calibrator 44 and a BPF45, and is logarithmically amplified here. The amount of attenuation in the intermediate frequency amplifier 43 is controlled stepwise by the control unit 21, and the BPF 45 can select BW having, for example, 3 MHz, 1 MHz, 300 KHz or 100 KHz. .

The output of the logarithmic amplifier 46 is displayed on the LED display 50 via the amplifier 48 and the A / D converter 49 after the noise component is removed by the video filter 47. Also, A / D converter
The output of 49 is displayed on the S meter 52 via the D / A converter 51, and is also supplied to a recorder (not shown) via the amplifier 53 for recording.

When the microwave transmitter / receiver 20 is operated as a transmitter, the switching terminal 27 and the TX output terminal 35 are connected and the circuits after the BPF 29 do not operate.

The operation of this embodiment will be described below.

FIG. 4 shows a schematic flow of the operation in the automatic measuring system of this embodiment. First, after connecting the cables to the measuring equipment at the transmitting station and the receiving station, turn on the power to start up the personal computer system, and set the transmitting station to the transmitting mode and the receiving station to the receiving mode for peripheral devices. To initialize. After that, the transmitting station is in the standby state, and the receiving station side distinguishes the telephones (dial, push) and inputs the telephone number, frequency range setting, polarization plane setting, measurement date / data required for data・ Perform input processing such as station names.

When this input processing is completed, give a measurement start command from the receiving station, and then send the measurement conditions and output start request to the transmitter side by full-duplex communication according to the instruction from the receiving station PC. , Read data from the receiver in synchronization with the transmitting station, store it in the RAM of the personal computer, and display it on the screen. After that, when the measurement of the specified item in a certain frequency band is completed, enter the presence / absence of storage of the data taken into the personal computer in the floppy disk. If the data is not stored, the measurement operation of the measurement item is finished at that point. However, when the data is stored, the measurement operation of the measurement item is ended by the end of the operation.

FIG. 5 shows a sequence of normal system signals in the group branching filter crossing discrimination test and effective return loss measurement according to this embodiment, and FIG. 6 shows a flow chart of the operation.
The processing of the block indicated by the broken line in FIG. 6 indicates the external input processing by the operator. As is apparent from FIGS. 5 and 6, in this embodiment, the transmission and reception of the radio wave between the transmitting station and the receiving station are performed by the receiving station as the main station through the personal computer communication from the receiver of the own station. The transmitter of the transmitting station is controlled by the full-duplex communication method.

That is, in the transmitting station and the receiving station, after the system of the personal computer is started up and the peripheral devices are initialized, first, the personal computer of the receiving station gives a communication line connection command to the transmitting station. After that, when the line is connected and the communication line connection response is returned from the PC of the transmitting station to the PC of the receiving station, the PC of the receiving station gives an instruction to transmit the radio wave of frequency f1 to the PC of the transmitting station, which causes the transmitter to While transmitting the f1 vertically or horizontally polarized radio wave from the transmitter, the transmitter gives a transmission response of the f1 radio wave to the receiving station personal computer through the transmitting station personal computer.

From the PC of the receiving station, give the f1 receiving command to the receiver after the f1 sending command to the sending station, and after the f1 sending response from the sending station,
When the response of receiving f1 is returned from the receiver, a data acquisition command is given to the receiver to send out the data and the data is acquired. Next, an input end change command is given to the receiver, whereby the coaxial switch 26 shown in FIG. 3 is switched to change the measurement end from the vertical polarization input terminal 25-1 to the horizontal polarization input terminal 25.
-Switch to -2 or vice versa. Then from the receiver
When the response that receives f1 is returned, give a data capture command to the receiver to send out the data and capture it.

From the above, if the data of the vertical and horizontal polarization components at the receiving station for the vertically or horizontally polarized radio waves of the frequency f1 transmitted from the transmitting station is taken in to the personal computer of the receiving station,
The measurement data is processed and the screen is displayed.

After that, when the processing for the frequency f1 is completed, the receiving station personal computer sends a signal to the transmitting station personal computer at 1 MHz higher than the frequency f1.
Give a command to transmit radio waves of high or low frequency f2. As a result, the personal computer of the transmitting station gives the transmitter a command to end f1 transmission, and when the transmitter returns a response (RF OFF) indicating the end of f1 transmission, it sends a command to send f2 to the transmitter. In the transmitter, the f2 radio wave is transmitted by the f2 transmission command from the personal computer of the transmitting station, and the transmission response of the f2 radio wave is given to the personal computer of the receiving station via the personal computer of the transmitting station. After that, in the same manner, the reception data of the vertical and horizontal polarization components of the f2 radio wave is captured and processed by the receiving station.

For the above measurement, 1
The same operation is performed while shifting in MHz steps, and when the required measurement is completed, measurement data storage processing or disposal processing is performed. After that, external processing such as termination processing or continuation processing and measurement item change processing is performed, and when the termination processing is input, the measurement data is printed out.

In the antenna-to-group duplexer opposite cross discrimination test, the single frequency near the center is transmitted in each frequency band used, and the horizontal and vertical polarization components are received. In the above measurement, the generation of radio waves from the transmitting station is prohibited, and the receiving station operates so as to measure the received data of the horizontal and vertical polarization components in the used frequency band in 1 MHz steps.

Further, in this embodiment, in addition to the normal system signal sequence shown in FIG. 5, there is a fault other than the forced termination process for forcibly ending the transmission of the transmission radio wave, the measurement interruption process for temporarily suspending the measurement, and the communication system process. There is a process at the time of failure occurrence when an error occurs. FIGS. 7 to 9 show signal sequences in each case. FIG. 7 shows a signal sequence at the time of forced termination, FIG. 8 shows a signal sequence at the time of measurement interruption, and FIG. 9 shows a signal sequence at the time of failure occurrence. .

FIG. 10 shows a flow chart of measurement processing at the receiving station in this embodiment, and FIG. 11 shows a detailed flow chart of data reading and file processing in the flow chart shown in FIG. In this example, in order to obtain the measurement data in a state where the receiver is in a stable state, the data is sequentially captured 35 times in each measurement, the first 25 times of the data are discarded, and the remaining 10 times of the data are collected. The maximum value and the minimum value are discarded, and the average value of the remaining 8 data is taken as the measurement data.

As described above, according to this embodiment, as shown in FIG. 2, the communication adapter, the personal computer, and the microwave transmitter / receiver are arranged in the transmitting station and the receiving station, respectively, and these are connected via the telephone line. Since the receiver station is the main station and the receiver controls the transmitter of the transmitter station through full-duplex communication through personal computer communication, the various characteristics of the microwave antenna system are automatically measured. Can be performed easily and quickly, and the measuring device can be inexpensive.

It should be noted that the present invention is not limited to the above-described embodiments, and many modifications and variations are possible. For example,
In the above-described embodiment, the microwave transmitter / receiver having the same configuration is used, and the terminals are switched to operate as a transmitter and a receiver. However, a transmitter / receiver dedicated receiver may be used. . Further, the present invention can be effectively applied not only to a shared antenna system of a plurality of bands but also to characteristic measurement of an antenna system of a single band or an antenna system that transmits / receives radio waves of a single polarization.

〔The invention's effect〕

As described above, according to the present invention, a microwave transmitter capable of transmitting microwaves in a predetermined frequency step and its control device are arranged in the transmitting station, and a microwave is transmitted in a predetermined frequency step to the receiving station. A microwave receiver that can receive waves and its arithmetic and control unit are arranged, and the control unit on the transmitting station side and the arithmetic and control unit on the receiving station side are connected by a telephone line. The microwave transmission and the microwave reception at the microwave receiver are performed by the reception station as the main station by the full-duplex communication system by the arithmetic controller of the receiving station and the controller of the transmitting station. Since the characteristics of the microwave antenna system between the transmitting station and the receiving station are automatically controlled by the control, desired measurement can be performed easily and quickly, and the measuring device can be inexpensive.

[Brief description of drawings]

FIG. 1 is a system diagram showing an example of an automatic measurement system for microwave antenna system characteristics for fixed communication for carrying out the present invention, and FIG. 2 is a diagram showing concrete connections of measuring equipment in one embodiment of the present invention. FIG. 3 is a block diagram showing the configuration of an example of the microwave transceiver shown in FIG. 2, FIG. 4 is a flowchart showing the outline of the operation in the automatic measurement system using the measuring equipment shown in FIG. 2, and FIG. Similarly, a sequence diagram of a normal system signal in the measurement of that example, FIG. 6 is a flowchart of its operation, and FIGS. 7, 8, and 9 are forced termination processing, respectively.
Signal sequence diagrams of measurement interruption processing and failure occurrence processing, and FIGS. 10 and 11 are flowcharts showing the operation of the measurement processing at the receiving station. 1 ... Microwave transmitter, 2 ... Control device 3 ... Communication adapter, 4 ... Telephone 5 ... Microwave receiver, 6 ... Arithmetic control device 7 ... Communication adapter, 8 ... Telephone 11,12 …… Microwave antenna 13 …… telephone line, 15 …… telephone line 16 …… RS-232C connection cable 17 …… PC, 18 …… expansion board 19 …… GP-IB connection cable 20 …… microwave transmission / reception Machine

Claims (1)

[Claims] 1. When measuring the characteristics of a microwave antenna system between a fixed communication transmitting station and a receiving station, the transmitting station transmits microwaves through a microwave antenna system of the transmitting station at predetermined frequency steps. A microwave transmitter capable of transmitting and a control device therefor are arranged, and a microwave receiver capable of receiving a microwave at a predetermined frequency step through the microwave antenna system of the receiving station and the receiving station. An arithmetic and control unit is arranged, and a telephone line is connected between the control unit on the transmitting station side and the arithmetic and control unit on the receiving station side, and from the microwave transmitter via the telephone line. The transmission of microwaves and the reception of microwaves at the microwave receiver are performed by the arithmetic control unit on the receiving station side and the control unit on the transmitting station side with the receiving station as a main station. two Controlled by a dual communication system, the characteristics of the microwave antenna system between the transmitting station and the receiving station are automatically measured by the arithmetic and control unit based on the input electric field of the microwave received by the microwave receiver. An automatic measurement system for the characteristics of microwave antenna systems for fixed communications, which is characterized in that