KR20010087979A - Channel selector for wireless repeater having gain adjusting funcution, and channel selecting type wireless repeater using the same - Google Patents

Abstract

PURPOSE: A channel selecting apparatus for a wireless repeater having a gain adjusting function and wireless repeater with a channel selection type using the same is provided to selectively execute a wireless relay to a plurality of communication companies and automatically execute a gain adjustment to a selected communication channel. CONSTITUTION: A mixer(21) mixes a certain local oscillation frequency(L0) to an inputted RF signal and generates an IF signal. A signal splitting unit(22) splits the IF signal inputted from the mixer(21) as a plurality of signals. A filter unit(23) filters each frequency signal outputted from the signal splitting unit(22) and divides each frequency according to a channel assigned to each communication company to output the divided frequency. The filter unit(23) has a plurality of BPFs(231-23n). A plurality of gain adjusting units(241-24n) adjust signal gains of band signals outputted from the BPFs(231-23n) so that signal intensities of the band signals are uniform. A signal synthesizer(25) synthesizes output signals of the gain adjusting units(241-24n). A mixer(26) mixes the local oscillation frequency(L0) with a signal outputted from the signal synthesizer(25).

Description

Channel selector for wireless repeater having gain adjustment function, and channel selector repeater using same {Channel selector for wireless repeater having gain adjusting funcution, and channel selecting type wireless repeater using the same}

The present invention relates to a wireless repeater of a mobile communication system, and more particularly, to a wireless repeater having a gain control function for automatically executing a gain adjustment for a selected communication channel in addition to selectively performing a radio relay for a plurality of carriers. The present invention relates to a channel selector for use and a channel selector type repeater using the same.

Recently, as the communication technology is rapidly developed, a mobile communication system that enables a user to execute a call while moving is developed and rapidly spread. In such a mobile communication system, a communication service area is divided into predetermined cell units, and a base station per cell is provided to provide a communication function to a terminal owned by a user.

However, in a general urban area or a mountainous area, the line of sight between the base station and the terminal is blocked by a high-rise building or a high mountain, and the user who owns the terminal is in a building. Likewise, a problem occurs in that the viewing distance between the base station and the terminal is blocked. In the case of the shadow area in which the viewing distance is blocked as described above, the frequency is not smoothly transmitted and received between the base station and the terminal, thereby causing a problem in that the call is disconnected. In addition, in order to solve such a problem, it may be considered to remove the shadow area by reducing the cell area that is controlled by one base station, but in this case, there is a problem that additional expensive base station should be installed.

Therefore, in recent years, a method of installing a repeater for relaying a transmission / reception frequency between a terminal and a base station in a building or another shaded area has been widely used. However, in the case of the repeater, since the relay function is performed only for a specific base station, the number of repeaters installed in a single area increases as the number of communication operators performing mobile communication business increases, which is unnecessary for the service provider. This leads to an increase in costs.

On the other hand, in consideration of the above circumstances, a method of sharing a repeater with a plurality of communication providers is considered. However, in this case, since the transmit and receive frequency signal strengths of the base stations owned by each communication provider are different from each other, it is necessary to match the signal strengths with each other. That is, in Fig. 1, for example, a carrier A of 869 to 880 MHz and a C band of 890 to 894 MHz are used by a carrier "A", and a carrier of "B" of 880 to 890 MHz is used. In this case, since the A and C bands are used by the same carrier, the signal strengths remain the same, whereas the B band is used by other carriers. The signal strength is set to be smaller or larger than that of the signal in the C signal band, and if the signals having different signal strengths are amplified to the same gain level, the output signal strength becomes too low or too high so that normal communication is achieved. There is a problem of not providing a function.

Therefore, some repeaters recently implemented have a configuration in which a repeater corresponding to each communication channel is separately manufactured and then mixed into one main body.

However, in the integrated repeater described above, the design specifications of the repeater are changed to suit the communication environment of the region where the repeater is installed, for example, the number and frequency bands of the communication channels to which the repeater should relay, and the frequency strength of the repeating channel. There is a problem that the production and installation is not so easy.

Accordingly, the present invention has been made in view of the above circumstances, and it is possible to perform a relay function by selecting a plurality of band signals with a simple configuration, and of course, a gain capable of constantly adjusting the signal strength for each band signal. It is an object of the present invention to provide a channel selector for a wireless repeater having an adjustment function.

In addition, another object of the present invention is to provide a channel selection type wireless relay apparatus having the above-described channel selection apparatus so that it can appropriately respond to various installation environments.

1 is a view showing signal bands assigned to respective service providers and signal strengths in each signal band as an example.

2 is a block diagram showing a channel selection apparatus for a wireless repeater having a gain adjustment function according to an embodiment of the present invention.

3 is a configuration diagram showing an example of the configuration of the gain adjusting unit 24 in FIG.

4 is a configuration diagram showing another configuration example of the filter unit 23 in FIG. 2.

5 is a block diagram showing a channel selection apparatus for a wireless repeater having a gain adjustment function according to another embodiment of the present invention.

Figure 6 is a block diagram showing the configuration of a channel selection wireless repeater according to the present invention.

**** Brief description of the main parts of the drawing ****

61, 62: duplexer, 70, 71: signal path,

71, 73, 75, 81, 83, 85: amplifier, 72, 82: attenuator,

74, 84: channel selector.

A channel selector for a wireless repeater having a gain adjustment function according to a first aspect of the present invention for realizing the above object comprises: a first mixer for generating an intermediate frequency signal by mixing a predetermined local oscillation frequency with respect to an input high frequency signal; Frequency dividing means for dividing the frequency signal output from the first mixer into a plurality of frequency signals, filter means for separating and outputting the frequency signal output from the frequency dividing means for each communication channel, and at each output end of the filter means. A plurality of gain adjusting means for combining and setting the signal strengths of the frequency signals input from the filter means to the same value; a signal synthesizing means for synthesizing the output frequency signals of the respective gain adjusting means; and an output frequency of the signal synthesizing means. And a second mixer for mixing and outputting a predetermined local oscillation frequency with respect to the signal. Characterized in that comprised over.

In addition, the channel selection apparatus for a wireless repeater having a gain adjustment function according to the second aspect of the present invention is coupled to the frequency distribution means for branching the input high frequency signal into a plurality of frequency signals, and the output from the frequency distribution means, respectively; In addition, a plurality of first mixers that mix different local oscillation frequencies with respect to the input frequency signal, respectively, are coupled to the plurality of first mixers, and have the same bandpass characteristic, and have a predetermined band from the input frequency signal. A plurality of band pass filters for filtering and outputting a frequency signal, a plurality of gain adjusting means coupled to each output terminal of the band pass filter, and setting signal strengths of the frequency signals input from the filter means to the same value; Coupled to the output of the adjusting means, Each including mutually different local oscillation number of the second mixer and the signal synthesizing means for synthesizing the output frequency signal of the second mixer for mixing the output frequency is characterized in that configured.

Further, the gain adjusting means includes attenuation means whose attenuation gain is set according to the gain adjustment voltage, amplifying means for amplifying the output frequency signal of the attenuation means, and envelope detection means for detecting an envelope of the output frequency signal of the amplifying means. And an integrating means for integrating the envelope signal detected by the envelope detecting means to generate a gain adjustment voltage.

In addition, the channel selectable wireless relay device according to the third aspect of the present invention includes a first duplexer for separating transmission and reception frequency signals for a base station, a second duplexer for separation of transmission and reception frequency signals for a terminal, and the first and second operations. First and second amplifying means provided between the two duplexers, first and second amplifying means respectively provided on the first and second signal paths and amplifying a frequency signal transmitted through the corresponding signal paths; And channel selection means for selecting frequency signals transmitted on the first and second signal paths respectively and transmitted through the corresponding signal paths.

According to the present invention having the above-described configuration, the input high frequency signal is separated for each channel corresponding to each communication service provider through a filter means, and each separated frequency signal is attenuated to attenuation level proportional to the signal strength by the gain adjusting means. After the gain adjustment is performed, the signal is synthesized by the signal synthesizing means and regenerated into the original frequency signal. Therefore, the relay channel can be easily selected by the filter means, and the frequency signal output through the signal synthesizing means has an overall uniform signal level regardless of the channel.

Hereinafter, an embodiment according to the present invention will be described with reference to the drawings.

2 is a block diagram showing a channel selection apparatus for a wireless repeater having a gain adjustment function according to an embodiment of the present invention.

In FIG. 2, reference numeral 21 denotes a mixer which generates an intermediate frequency signal by mixing a predetermined local oscillation frequency L0 with respect to an input high frequency signal, and 22 denotes a plurality of signals of the intermediate frequency signal input from the mixer 21. This is a signal distribution unit for branching and outputting. Here, the signal distributed by the signal splitter 22 is set to correspond to the number of channels that the present wireless repeater will accommodate. In addition, a band pass filter may be employed between the mixer 21 and the signal divider 22 to filter the sum frequency signal of the input high frequency signal and the local oscillation frequency or the difference frequency signal.

In addition, reference numeral 23 denotes a filter unit for filtering each frequency signal output from the signal distribution unit 22 and separating the frequency signal for each band, that is, for each channel assigned to each communication service provider. The filter section 23 is composed of a plurality of band pass filters (BPF) 23 _{1 to} 23 _n each having different band pass characteristics, and each band pass filter 23 _{1 to} 23 n is assigned to a communication service provider, respectively. It has a passband characteristic corresponding to the channel band.

Further, reference numeral 24 (24 _{1 to} 24 n) is a gain adjusting section for adjusting the signal gain so that the signal strength of the band signal output from each of the band pass filters 23 _{1 to} 23 n has a constant value. .

Reference numeral 25 denotes a signal synthesizer for synthesizing and outputting the output signals from the respective gain adjusting units 24 _{1 to} 24n, and 26 denotes a predetermined local oscillation frequency L0 with respect to the signal output from the signal synthesizer 25. ) Is a mixer that produces the original high frequency signal by mixing

3 is a block diagram showing the configuration of each of the gain adjusting units 24 _{1 to} 24n. In the drawing, reference numeral 241 denotes an attenuator which attenuates the gain of the signal input from the bandpass filter BPF according to the adjustment voltage applied from the integrating circuit 244, which will be described later, which is a voltage input from the integrating circuit 244. The attenuation level increases in proportion to. The frequency signal output from the attenuator 241 is output to the signal synthesizer 25 of FIG. 2 through the amplifier 242. Reference numeral 243 denotes an envelope detector which detects an envelope of the frequency signal output from the amplifier 242, and 244 integrates an envelope signal output from the envelope detector 243 and sets the integral level to the attenuator ( This is an integrating circuit which outputs as attenuation gain adjustment voltage for 241).

2 and 3, when a high frequency signal is input, first, the mixer 21 is mixed with a predetermined local oscillation frequency to generate an intermediate frequency signal, and the intermediate frequency signal generated in this manner is a signal divider 22. The signal is distributed through a plurality of signals. In addition, the plurality of signals output through the signal splitter 22 are separated by each channel, that is, by band frequency signals corresponding to each communication provider, from the filter unit 23 and input to the gain adjusting unit 24.

On the other hand, the frequency signal input to the gain adjusting section 24 is adjusted by the gain adjusting section 24 so that the signal level is adjusted as a signal having a constant level. That is, in FIG. 3, the frequency signal input from the band pass filter is input to the signal synthesizer 25 through the attenuator 241 and the amplifier 242. Here, the amplifier 242 is amplified gain is set in consideration of the case where the level of the input frequency signal is a minimum value. The attenuator 241 is set to a level proportional to the strength of the frequency signal output from the amplifier 242 so that the signal strength output through the amplifier 242 always has a constant value. That is, since the envelope of the output frequency signal of the amplifier 242 is detected by the envelope detector 243, and the detected envelope signal is integrated by the integrating circuit 244, the level signal output from the integrating circuit 244. Has a level value corresponding to the signal strength of the frequency signal output from the amplifier 242. The attenuator 241 sets the attenuation in proportion to the signal level output from the integrating circuit 244, and sets the attenuation degree large when the level of the frequency signal input to the signal synthesizer 25 is high. When the level of the frequency signal is low, the attenuation is set low. therefore. In the configuration of FIG. 3, the attenuation gain of the attenuator 241 is variably set according to the strength of the frequency signal output from the amplifier 242, that is, the frequency signal input from the bandpass filter. To have a constant value.

Subsequently, in FIG. 2, the gain-adjusted frequency signal output from each gain adjusting unit 24 is again synthesized by the signal synthesizer 25, and the synthesized frequency signal is mixed again with the local oscillation frequency by the mixer 26. And output as an original frequency signal. Of course, even in this case, it may be preferable to provide a predetermined bandpass filter at the rear end of the mixer 26 to remove the noise signal generated by the mixing operation.

That is, in the above embodiment, the input frequency signal is separated for each channel corresponding to each communication provider through the filter unit 23, and each of the separated frequency signals is attenuated by the gain adjusting unit 24 in proportion to the signal strength. After the gain adjustment is attenuated by the signal synthesizer 25, it is synthesized by the signal synthesizer 25 to reproduce the original frequency signal. Therefore, the frequency signal output through the signal synthesizer 25 has an overall uniform signal level regardless of the channel.

Further, the band pass characteristics of the band pass filters 23 _{1 to} 23 _n included in the filter unit 23, the number of installation thereof, or the frequency of the local oscillation frequency L0 mixed through the mixers 21 and 26 are adjusted. Through this method, the number or band of channels output through the device can be selected.

Meanwhile, FIG. 4 shows another configuration example of the filter unit 23 in FIG. 2, which is provided with switches SW1 to SWn at the rear ends of the band pass filters 23 _{1 to} 23 n, respectively. _It is configured to selectively output the output frequency signal of _{1 to} 23n). That is, in the configuration shown in Fig. 2, the outputs of the band pass filters 23 _{1 to} 23 n are unconditionally inputted to the signal synthesizer 25 through the gain adjusting unit 24. It is desirable to consider the channels that will be accommodated. However, if the filter unit 23 shown in FIG. 4 is employed, the band pass filters 23 _{1 to} 23 n and the gain adjusting unit 24 are installed corresponding to all communication channels, and then the switches SW1 to SW n are necessary. By selectively turning on / off, it is possible to cope with the use environment of the wireless repeater. That is, since the wireless repeater may be configured to be constant regardless of its installation environment, the manufacture of the wireless repeater becomes easy.

On the other hand, in the embodiment shown in Fig. 2, since each band pass filter 23 _{1 to} 23 _n constituting the filter unit 23 should filter different communication channels, the filtering characteristics of the band pass filters 23 _{1 to} 23 n are respectively determined. There is a problem to design differently.

5 is a block diagram showing a channel selector for a wireless repeater having a gain adjustment function according to another embodiment of the present invention in consideration of the above circumstances.

In the configuration of FIG. 5, the input frequency signal is branched into a plurality of signals through the signal splitter 51. Here, the number of frequency signals branched by the signal splitter 51 corresponds to the number of channels accommodated in the repeater. Subsequently, the frequency signals output from the signal divider 51 are mixed with different local oscillation frequencies L0 to Ln through the mixers 52 _{1 to} 52n, respectively. At this time, the local oscillation frequency (L0~Ln) are each of the mixers (52 ₁ ~52n) is set to correspond to the frequency of the channel signal input to the frequency signal for each communication channel is output from the mixer (52 ₁ ~52n) Will have the same intermediate frequency. The intermediate frequency signals output from the mixers 52 _{1 to} 52n are filtered by the band pass filters 53 _{1 to} 53n having the same band pass characteristics to be input to the gain adjusting units 54 _{1 to} 54n.

On the other hand, the gain adjusting sections 54 _{1 to} 54n have substantially the same configuration as the gain adjusting section described in FIG. That is, each gain adjusting section 54 _{1 to} 54n adjusts the signal gain to an attenuation level corresponding to the strength of the input frequency signal so that the strengths of the frequency signals output from the gain adjusting sections 54 _{1 to} 54n are equal to each other. To have it. Then, the gain-adjusted frequency signal for each channel is mixed with a predetermined local oscillation frequency (L0 to Ln) by the mixers 55 _{1 to} 55n, respectively, and converted into an original frequency signal, and then the signal synthesizer 56 is used. It is synthesized through the output. Although not shown in the drawings, it is preferable to provide a band pass filter at the rear end of each of the mixers 55 _{1 to} 55 n or at the rear end of the signal synthesizer 56 to remove the noise signal generated by the mixing operation. It may be desirable.

In the above embodiment, different local oscillation frequencies are mixed with a plurality of high frequency signals output from the signal splitter 51 so that the frequency channels for each service provider have the same intermediate frequency. Therefore, in the above embodiment, those having the same bandpass characteristics as the bandpass filters 53 _{1 to} 53n can be used.

6 is a block diagram showing a channel selection type wireless repeater according to the present invention having the channel selection apparatus.

In FIG. 6, reference numerals 61 and 62 are duplexers for separating transmission and reception frequencies. In addition, an amplifier for amplifying the frequency signal transmitted on each path is provided while the paths 70 and 80 of the frequency signal transmitted from the terminal to the base station or from the base station to the terminal are provided between the duplexers 61 and 62. 71, 73, 75 (81, 83, 85) and attenuators 72, 82 are provided respectively. Here, the attenuators 72 and 82 are for preventing the saturation of the frequency signals input to the amplifiers 73 and 83, respectively, and adjusting the overall amplification gain for the transmit and receive frequency signals.

In addition, channel selection devices 74 and 84 are provided on the signal paths 70 and 80, respectively. The channel selectors 74, 84 correspond to Figs. 2, 4 and 5, which select a channel relayed by the present relay device and set the signal strength between the selected channels to be the same. Will be performed.

That is, in the above configuration, the signal strengths relayed through the channel selectors 74 and 84 are selected, and the signal strengths between the channels are set to be the same, and the same signal strengths are set to the amplifiers 71, 73, and 75. 81, 83, 85 and attenuators 72, 82 are collectively amplified and sent to the base station or the terminal.

Therefore, in the above embodiment, the configuration of the wireless repeater can be simplified, and it can meet various installation environments.

In addition, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the technical scope of the present invention. The present invention may be limited only by the claims herein.

As described above, according to the present invention, a wireless relay having a gain adjustment function capable of executing a relay function by selecting a plurality of band signals with a simple configuration and of uniformly adjusting signal strength for each band signal. A channel selector for use and a channel selector type wireless repeater can be realized.

Claims (13)

A first mixer for generating an intermediate frequency signal by mixing a predetermined local oscillation frequency with respect to an input high frequency signal; Frequency dividing means for branching the frequency signal output from the first mixer into a plurality of frequency signals; Filter means for separating and outputting the frequency signal output from the frequency distribution means for each communication channel, A plurality of gain adjusting means coupled to each output end of the filter means and setting the signal strengths of the frequency signals inputted from the filter means to the same value; Signal synthesizing means for synthesizing the output frequency signal of each gain adjusting means; And a second mixer for mixing and outputting a predetermined local oscillation frequency with respect to the output frequency signal of the signal synthesizing means. The method of claim 1, And said filter means comprises a plurality of band pass filters each having a different band pass characteristic. The method of claim 2, And a switching means at an output end of the band pass filter. The method of claim 1, The gain adjusting means includes attenuation means whose attenuation gain is set according to the gain adjusting voltage; Amplifying means for amplifying the output frequency signal of the attenuation means; Envelope detection means for detecting an envelope of an output frequency signal of said amplifying means; And integrating means for integrating an envelope signal detected by said envelope detecting means to generate a gain adjusting voltage. Frequency dividing means for branching the input high frequency signal into a plurality of frequency signals; A plurality of first mixers each coupled to an output from the frequency distribution means and mixing different local oscillation frequencies with respect to an input frequency signal; A plurality of band pass filters which are coupled to each of the plurality of first mixers and have the same band pass characteristics, respectively, and filter and output a frequency signal of a predetermined band from an input frequency signal, A plurality of gain adjusting means coupled to each output end of the band pass filter and setting the signal strengths of the frequency signals input from the filter means to the same value; A plurality of second mixers which are respectively coupled to the outputs of the gain adjusting means and which mix and output different local oscillation frequencies with respect to the output frequency signals; And a signal synthesizing means for synthesizing the output frequency signal of the second mixer. The method of claim 5, The gain adjusting means includes attenuation means whose attenuation gain is set according to the gain adjusting voltage; Amplifying means for amplifying the output frequency signal of the attenuation means; Envelope detection means for detecting an envelope of an output frequency signal of said amplifying means; And integrating means for integrating an envelope signal detected by said envelope detecting means to generate a gain adjusting voltage. A first duplexer for separating transmission and reception frequency signals for the base station; A second duplexer for separating transmission and reception frequency signals for the terminal; First and second signal paths provided between the first and second duplexers, First and second amplifying means respectively installed on the first and second signal paths and amplifying the frequency signals transmitted through the corresponding signal paths; And channel selection means for selecting frequency signals transmitted on the first and second signal paths respectively and transmitted through the corresponding signal paths. The method of claim 7, wherein The channel selecting means includes a first mixer for generating an intermediate frequency signal by mixing a predetermined local oscillation frequency with respect to an input high frequency signal; Frequency dividing means for branching the frequency signal output from the first mixer into a plurality of frequency signals; Filter means for separating and outputting the frequency signal output from the frequency distribution means for each communication channel, A plurality of gain adjusting means coupled to each output end of the filter means and setting the signal strengths of the frequency signals inputted from the filter means to the same value; Signal synthesizing means for synthesizing the output frequency signal of each gain adjusting means; And a second mixer for mixing and outputting a predetermined local oscillation frequency with respect to the output frequency signal of the signal synthesizing means. The method of claim 8, And the filter means comprises a plurality of band pass filters each having a different band pass characteristic. The method of claim 9, And a switching means at an output end of the band pass filter. The method of claim 8, The gain adjusting means includes attenuation means whose attenuation gain is set according to the gain adjusting voltage; Amplifying means for amplifying the output frequency signal of the attenuation means; Envelope detection means for detecting an envelope of an output frequency signal of said amplifying means; And integrating means for integrating an envelope signal detected by said envelope detecting means to generate a gain adjustment voltage. The method of claim 7, wherein The channel selecting means comprises: frequency distribution means for branching an input high frequency signal into a plurality of frequency signals; A plurality of first mixers each coupled to an output from the frequency distribution means and mixing different local oscillation frequencies with respect to an input frequency signal; A plurality of band pass filters which are coupled to each of the plurality of first mixers and have the same band pass characteristics, respectively, and filter and output a frequency signal of a predetermined band from an input frequency signal, A plurality of gain adjusting means coupled to each output end of the band pass filter and setting the signal strengths of the frequency signals input from the filter means to the same value; A plurality of second mixers which are respectively coupled to the outputs of the gain adjusting means and which mix and output different local oscillation frequencies with respect to the output frequency signals; And a signal synthesizing means for synthesizing the output frequency signal of the second mixer. The method of claim 12, The gain adjusting means includes attenuation means whose attenuation gain is set according to the gain adjusting voltage; Amplifying means for amplifying the output frequency signal of the attenuation means; Envelope detection means for detecting an envelope of an output frequency signal of said amplifying means; And integrating means for integrating an envelope signal detected by said envelope detecting means to generate a gain adjustment voltage.