JPH0766775A - Repeating amplifier device - Google Patents

Abstract

PURPOSE:To inexpensively obtain a repeating amplifier device exclusively for outgoing signals capable of repeatedly amplifying only a frequency channel for a specific communication service company by providing the amplifier device with a distributer, individual receivers for amplifying outputs from the distributers in each narrow band of a prescribed channel and a synthesizer for synthesizing outputs from respective individual receivers and inputting the synthesized result to a common amplifier. CONSTITUTION:A radio wave from a radio wave base station is limited to a radio wave calling frequency band through a filter 8, the limited wave is amplified by a low noise amplifier 9 and distributed by an n-distributer 4 and respective distributed components are inputted to individual narrow band receivers 5-1 to 5-n set up to respective exclusive frequency bands. After removing unwanted bands through the receivers 5-1 to 5-n, outputs from the receivers 5-1 to 5-n are synthesized by an n-synthesizer 7. The synthetic output is amplifier by a common amplifier 3 and the band of the amplified output is limited by a filter 10 and band-limited output is sent from a transmitting antenna 2 to a mobile station. A control part 6 has a function for controlling synthesizers built in the receivers 5-1 to 5-n and setting up the exclusive frequency bands.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a relay amplifying device installed in an underground mall or the like as a dead zone countermeasure in a radio calling system or the like.

[0002]

2. Description of the Related Art Recently, there has been an increasing demand for a radio call service even in a dead zone such as an underground shopping area where radio waves do not reach. Therefore, a relay amplification device that relays and amplifies the wave transmitted from the base station has come to be installed. FIG. 3 is a schematic diagram of a conventional relay amplifier. The radio wave from the radio base station is received by the antenna 1, amplified by the relay amplifier 3, and transmitted from the antenna 2 to the mobile station (radio call receiver) existing in the dead zone. This method has the advantage of being inexpensive because it amplifies all the received waves in the radio paging frequency band input to the relay amplifier 3. However, currently, there are multiple radio paging communication service companies in the same area, and frequency allocation is randomly assigned to each company within the radio calling frequency band. Since the service of amplifying and relaying the frequency of is also performed, the superiority of the service is lost. Figure 4
[Fig. 3] is a block diagram showing a configuration example conceivable for solving the above problem. In the configuration shown in FIG. 4, the reception duplexer 20 and the transmission duplexer 3 each including a filter that allows a plurality of channel frequencies assigned to the service company to pass therethrough.
Since 0 must be manufactured, it becomes very expensive. In addition, since the channel spacing is minimum and several tens of kHz, it is practically impossible to manufacture a filter. 21 ~
2n is an individual amplifier.

[0003]

As described above, when channels assigned to a plurality of service companies coexist within a predetermined radio call frequency band, a conventional relay amplifier installed in a dead zone provides a service. However, there is a problem in that there is no significant difference between the two, and it is not practical to individually select and amplify with a duplexer.

An object of the present invention is to inexpensively provide a downlink dedicated repeater amplifier device capable of repeating and amplifying only a frequency channel for a specific communication service company.

[0005]

A relay amplifier apparatus of the present invention receives a radio wave from a radio base station, amplifies a signal in a predetermined frequency band by a common amplifier, and sends it to a mobile station existing in a dead zone. In the relay amplification device, a distributor that receives the radio wave from the radio base station and distributes and outputs the signal in the predetermined frequency band to a predetermined number in the front stage of the common amplifier, and an output of the distributor is specified. A plurality of individual receivers for performing narrow band amplification for each channel, and a combiner for combining the outputs of the individual receivers and inputting to the common amplifier are characterized.

Further, the plurality of individual receivers are characterized in that they are configured to convert to an intermediate frequency having a frequency lower than that of the input signal and selectively amplify.

[0007]

FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, 1 is a receiving antenna, 2 is a transmitting antenna, 3 is a common amplifier, 4 is an n-distributor, 6 is a controller, 5
(5-1 to 5-n) are narrow band individual receivers, 7 is an n combiner, 8 and 10 are radio call frequency pass filters, and 9 is a low noise amplifier. Radio waves coming from the radio base station coming from the receiving antenna 1 are limited by the filter 8 to the radio call frequency band, then amplified by the low noise amplifier 9, distributed by the n distributor 4 and set to a dedicated frequency. The narrow band individual receivers 5-1 to 5-n are input. Narrowband receiver 5-1 for dedicated frequency of the service company
After removing unnecessary waves (waves for other communication service companies) at 5-n, they are combined by the n combiner 7. The combined output is amplified by the common amplifier 3 and band-limited by the filter 10 and then sent from the transmitting antenna 2 to the mobile station (radio call receiver). The controller 6 has a function of setting the dedicated frequency by controlling the synthesizer built in the dedicated frequency receivers 5-1 to 5-n. In the radio paging system, the frequency is fixed in the same area, so the dedicated frequency may be set first. Further, since the controller 6 can be controlled by remote control, it is convenient for maintenance.

FIG. 2 shows narrow band receivers 5-1 to 5- of the present invention.
An example of each configuration of n is shown. In the figure, 11 is a low noise amplifier, 12 is a mixer (MIX), 13 is an IF (intermediate frequency) filter, 14 is an IF amplifier, 15 is a local oscillator, 16 is a mixer (MIX), 17 is a spurious elimination filter, and 18 is It is an amplifier. The signal coming from the distributor 4 is amplified by the low noise amplifier 11, and is amplified by the MIX 12.
Converted to F. The frequency of the IF is lower than the input signal frequency and set to a frequency that can be realized by the filter that selects the individual channel. The low noise amplifier 11 may be omitted when a desired value is obtained in consideration of the noise figure of the entire relay amplification apparatus of FIG. The IF filter 13 is a narrow band filter, attenuates signals of adjacent channels (attenuates waves for other communication service companies), and inputs signals of one channel to the IF amplifier 14. The MIX 16 converts the IF frequency into the same frequency as the input received wave,
The output is a spurious eliminating filter 17 and an amplifier 18.
Is output to the combiner 7. In the vicinity of the boundary between the dead area and the normal service area, the wave passing through the repeater and the wave directly coming from the base station may overlap with each other. Therefore, the delay time difference between the respective waves is preferably small in terms of the reliability of the received signal. In order to reduce the delay time required for the repeater, it is necessary to reduce the delay of the IF filter 13, which is dominant in the entire device. Although it depends on the required attenuation amount of the adjacent frequency, it is possible to reduce the delay time by setting the IF frequency low. Since this method does not employ the filter sharing method as shown in FIG. 4, a loss of 10 log n is generated in the n distributor 4. Therefore, the low noise amplifier 9 for improving NF is provided. However, the repeater antenna installation position can be increased to reduce the propagation loss and the low noise amplifier 9 can be omitted.

[0009]

By implementing the present invention, an inexpensive distributor, combiner, and receiver are used, so that an inexpensive repeater is possible and only a specific frequency assigned to the service company can be amplified. , A service advantage over other communication service companies competing in the same frequency band can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a detailed view of a main part of the present invention.

FIG. 3 is a diagram illustrating a conventional configuration example.

FIG. 4 is a diagram illustrating a configuration example according to a conventional technique.

[Explanation of symbols]

 1, 2 antennas 3 common amplifier 4 distributor 5 narrowband individual receiver 6 control unit 7 combiner 8 BPF 9 low noise amplifier 10 BPF 11 low noise amplifier 12, 16 mixer 13 IF filter 14 IF amplifier 15 local oscillator 17 BPF 18 Amplifier 20, 30 Duplexer 21-2n Individual amplifier

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kenro Horizawa 2-3-13 Toranomon, Minato-ku, Tokyo International Electric Co., Ltd. (72) Inventor Tetsumasa Kato 2-3-13 Toranomon, Minato-ku, Tokyo International Electric Co., Ltd.

Claims (2)

[Claims] 1. A relay amplifying device for receiving a radio wave from a radio base station, amplifying a signal of a predetermined frequency band by a common amplifier, and transmitting the amplified signal to a mobile station existing in a dead zone, in a stage before the common amplifier. A distributor for receiving radio waves from a radio base station and distributing and outputting a predetermined number of signals in the predetermined frequency band, and a plurality of individual receivers for narrow-band amplifying the output of the distributor for each specific channel And a combiner for combining outputs of the individual receivers and inputting to the common amplifier. 2. The relay amplifier apparatus according to claim 1, wherein the plurality of individual receivers are configured to convert to an intermediate frequency having a frequency lower than that of an input signal and selectively amplify the intermediate frequency.