JPS63245136A - High frequency relay amplifier - Google Patents

Abstract

PURPOSE:To obtain a large power output while suppressing intermodulation by preparing a high gain directivity antenna in a direction of the base station and connecting an element having a narrow band selectivity for each channel and a power amplifier of narrow band. CONSTITUTION:A high gain/directivity antenna such as a parabolic antenna is used as a counter base station antenna 1. The radio wave received by the antenna 1 is branched by an antenna multicoupler 3, led to an n-distributer 5, an element 6a having a narrow band selectivity for control channel and a power amplifier 7a amplify the radio wave of control channel, the n- synthesizer 8 synthesizes outputs from elements 6b-6n for other channel and power amplifiers 7b-7n and the result is radiated in space through a counter mobile station antenna 2. Since the antenna 1 has a high gain, a high output effective radiation power is obtained even when a common amplifier 12 of the same scale.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a high frequency repeating amplifier for extending the service area of a base station using the same frequency in a cellular car telephone system or the like.

[Conventional technology]

An example of this kind of prior art is the one described in Telecommunication Research Institute Research Conference Proceedings No. 37 (Nippon Telegraph and Telephone Public Corporation Telecommunication Research Institute).

FIG. 4 is a block diagram showing the conventional relay amplification device. In the figure, (1) indicates the base station antenna, (2)
) is a mobile station antenna, +31 T4+ is an antenna sharing device, (9) is a 2-way splitter, (10a) (
22a) is an element with narrow band selectivity.

(10b) (22b) is an element with wideband selectivity, (Ill (23) is a combiner, and αz (24I) is a wideband power amplifier.

Next, the operation will be explained. Radio waves from the base station received by the base station antenna (1) are split by the antenna sharing device (3) and guided to the two-way splitter 01).

The radio waves distributed in the 2-way splitter circle are normally divided into elements with narrow band selectivity (2
2a) and 22b) with selectivity of the broadband allocated for the speech channel. The radio waves selectively amplified by these two antennas (22a) and (22b) are combined again by the 12 combiner (c), amplified by the common amplifier, and passed through the antenna duplexer (4) to the mobile station antenna ( 2) is reradiated. Radio waves received by the base station antenna (1) are reradiated at the same frequency by the mobile station antenna (2).

On the other hand, the radio waves from the mobile station received by the mobile station antenna (2) are split by the antenna duplexer (4), and then sent to the two-way splitter (2) through the same process as described above.

Narrowband element (10a) and wideband element (1
0b), 2 combiner (111, common amplifier uz color), and is further radiated from the base station antenna +11 through the antenna duplexer (3).

[Problems to be Solved by the Invention] Since the conventional high-frequency repeating amplifier is configured as described above, a plurality of radio waves are applied to the common amplifier (2) or the Q force, resulting in intermodulation. However, in order to suppress the unnecessary waves caused by the noise, a large output power cannot be obtained.

Furthermore, in the control channel, there is a drawback that the bit error rate of the digital signal increases due to mutual interference between the direct wave from the base station and the re-radiated wave from the repeater.

The present invention was made to solve the above-mentioned problems, and an object of the present invention is to realize a device that can suppress intermodulation and still obtain a large power output. It also aims to prevent mutual interference between direct waves and re-radiated waves on the control channel.

[Means for solving problems]

The high frequency relay amplifier device according to the present invention is intended to reduce output power in the upstream direction (toward the base station).

A high-gain directional antenna is prepared, and in the downstream direction (toward the mobile station), an element with narrowband selectivity is connected for each channel, and a narrowband power amplifier (usually class 0) is connected in series with this element. In particular, elements for control channels shift the channels of input and output signals (
In this case, the down converter and up converter each have separate local oscillator signal generators.

[Operation] The element having narrowband selectivity and the narrowband power amplifier of the present invention suppress intermodulation caused by interference of two or more waves by selectively amplifying radio waves for each channel. Furthermore, by shifting the frequencies of each of the input signal and output signal of the control channel, it is possible to prevent an increase in the bit error rate of the digital signal due to mutual interference between direct waves and reradiation.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, (1) uses a high gain/directivity antenna such as a parabolic antenna as the antenna for the base station. (2) is a mobile station antenna, which uses an omnidirectional or low gain directional antenna. +3), +4) are branching filters, (5) is n
(71) to (7n) are narrowband power amplifiers, (8) is an n combiner, and (9) is a two-way divider. , (101
1) and (10b) are elements having narrowband and wideband selectivity, αD is a 2-synthesizer, and a2 is a common amplifier.

The radio waves received by the base station antenna (1) are split by the antenna duplexer (3) and guided to the n-divider (5).

An element (6a) having narrow band selectivity for at least one control channel and a power amplifier (7a) connected in series with the element (6a) amplifies the radio wave of the control channel to a specified output, and performs n-synthesis. The output from the other speech channel elements (6b) to (6n) and the power amplifiers (7b) to (7n) are combined by the receiver (8), and then sent to the mobile station antenna (2) through the antenna duplexer (4). ) is radiated into space through

Radio waves received by the mobile station antenna (2) are either amplified through the same process as shown in Figure 4, or are amplified by the base station antenna (1).
) has a high gain, so even if a common amplifier of the same size is used, a high effective radiated power can be obtained.

FIG. 2 is a block diagram of an element with narrow band selectivity for the control channel used in the present invention, in which 3υ is a filter and preamplifier, (branch) is a down converter, and ■ is an intermediate Frequency filter, +34+ is intermediate frequency amplifier, can is up converter, (to) is filter and amplifier, □□□, C3B1 is local signal generator, ■ is high stability crystal oscillator, (4■ (411 is channel setting device) The input signal to the narrowband selection element is
selected and amplified by a filter and preamplifier Gll;
It is converted to an intermediate frequency of, for example, 45 MHz by a down converter (2). The output of the down converter ■ is selected by the intermediate frequency filter ■, amplified by the amplifier (goods), converted by the up converter (to), and then
Selected and amplified by filter and amplifier ■. In the channel setting device +40) - (41), channels can be set independently. For example, suppose that the down converter side is set to 100 channels and the up converter side is set to 102 channels. In the local signal generator (9), 10
Generates a local oscillator equivalent to channel 0, converts radio waves of 100 channels to intermediate frequency, selects and amplifies, and up converts.■
to be applied. In the up-converter can, a single-station signal generator ■ or a local signal generator equivalent to 102 channels is generated, so
Converts the intermediate frequency to radio waves equivalent to 102 channels. The highly stable crystal oscillator ■ supplies a common reference frequency to the local signal generator (9) (to), so the difference in frequency between the input signal and output signal to this element is exactly the difference equivalent to two channels. It can be done.

As a result, the output signal is re-radiated at a frequency different from the single signal frequency, so it is possible to prevent the input signal and the output signal from interfering with each other, and to maintain good λTa transmission. When the input signal and output signal have the same frequency, the two signals may interfere with each other due to delays occurring inside the element and delays caused by the difference in the propagation paths of direct waves and re-radiated waves when traveling through space. However, since this particularly has a negative effect on the propagation of digital signals, this can be removed by the channel shift described above.

In the above embodiment, a selective element is provided for each channel only in the down direction, but as shown in FIG. 3, a selective element can be provided for each channel in both up and down directions.

[Effects of the Invention] As described above, according to the present invention, since the re-radiation power can be increased, the relay amplifier can be installed far from the base station (in the ground), and the service area of the relay amplifier can be dramatically expanded. It becomes possible to provide services such as cellular car telephones with equipment that is cheaper than normal base station equipment.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a high frequency relay amplifier according to one embodiment of the present invention, FIG. 2 is a block diagram of an element having narrow band selectivity, and FIG. 3 is a block diagram showing another embodiment of the present invention. FIG. 4 is a block diagram showing a conventional high frequency repeating amplifier. (1) is the base station antenna, (2) is the mobile station antenna, (3+ +41 is the antenna sharing device, (5) is the n splitter - (6a) to (6n) have narrow band selectivity. Elements (7a) to (7n) are narrowband power amplifiers, (
8) is n combiner, (9) @ is 2 divider, (10a) (2
2a,) is an element with narrow band selectivity, (10
b) (22b) is an element with broadband selectivity;
no is a combiner, (IZ (241 is a wideband common amplifier,
3υ is a filter and preamplifier, @ is a down converter, ■ is an intermediate frequency filter, (to) is an intermediate frequency amplifier,
(to) is an up converter, (to) is a filter and amplifier, (to) is a local oscillator signal generator, ■ is a highly stable water oscillator, +4[) (41) is a channel setting device, (42 is an input terminal, Terminal is an output terminal. In the figures, the same reference numerals indicate the same or equivalent parts.

Claims (4)

[Claims] (1) In order to relay and amplify radio waves between a base station and a mobile station at the same frequency, an antenna for the base station, an antenna for the mobile station, a downlink element, a downlink common amplifier, an uplink element, and an uplink In a relay amplifier device having a common amplifier, an antenna duplexer, and a distributor, the antenna has a high gain directional antenna as the antenna for the base station, and in the down direction for relaying and amplifying radio waves from the base station, Each channel is equipped with an element having narrowband selectivity and a relatively narrowband power amplifier connected in series to the element, and at least one 1. A high frequency repeating amplifier comprising an element having narrow band selectivity of channels and a common power amplifier in series with the element. (2) The downstream power amplifier is configured with a class B or C class relatively narrowband power amplifier, and the upstream common amplifier is configured with a class A wideband power amplifier. A high frequency repeating amplifier according to claim 1, characterized in that: (3) Claims 1 or 2, characterized by having an element with narrow band selectivity for a control channel in the upstream direction and an element with wide band selectivity for a communication channel. The high frequency relay amplifier described above. (4) Elements with narrowband selectivity used for uplink control channels and downlink control channels have at least one receiving channel and one transmitting channel.
4. The high frequency repeating amplifier according to claim 1, wherein the high frequency repeating amplifier is shifted by more than one channel.