JP2016201682A - Am modulation signal synthesizer and am modulation signal transmitter - Google Patents

Abstract

In a technique for synthesizing a plurality of AM modulated signals having different carrier frequencies, PAPR (Peak Average Power Ratio) of the synthesized AM modulated signals while reducing power consumption, maintaining signal quality, and simplifying the device configuration Reduce. In the first means, phase setting units 146-1, 146-2,..., 146-N include a plurality of AMs so that the linearity of the input / output characteristics of the amplification unit 152 is maintained. Each phase of the modulation signal is set in a distributed manner. In the second means, the phase setting unit sets the phases of a plurality of carrier waves having different frequencies in a distributed manner so that the linearity of the input / output characteristics of the amplification unit 152 is maintained. In the third means, the phase setting unit disperses and sets the phases of the plurality of signals for modulating the plurality of carriers so that the linearity of the input / output characteristics of the amplification unit 152 is maintained. [Selection] Figure 2

Description

  The present invention relates to a technique for combining a plurality of AM modulated signals having different carrier frequencies.

  Re-broadcast the radio sound transmitted from the broadcasting station and received by the radio re-broadcast equipment toward the closed space such as the tunnel where radio waves are difficult to reach, and notify the emergency information in the closed space such as the tunnel. There is a technique for broadcasting interrupt sound (see, for example, Patent Document 1).

JP 2013-168773 A

  FIG. 1 is a block diagram showing a configuration of a conventional radio rebroadcast apparatus. Normally, N types of carrier waves having different frequencies are AM-modulated with N types of radio sounds # 1, # 2,..., #N, and N types of AM modulated signals are synthesized and amplified. In an emergency, N types of carrier waves having different frequencies are AM-modulated with interrupted speech having the same content, and N types of AM-modulated signals are synthesized and amplified.

  Here, an amplifier 152 having a high saturation level is used in preparation for a large PAPR (Peak Average Power Ratio) of the N types of AM modulation signals synthesized. Therefore, the power consumption of the amplification unit 152 cannot be reduced.

  In order to reduce the PAPR of the synthesized N types of AM modulated signals, limiters are applied to N types of radio voices # 1, # 2,. 141-1, 141-2,..., 141 -N are applied, and a CFR (Crest Factor Reduction) limiter 151 is applied to the synthesized N types of AM modulated signals. Therefore, the radio sound # 1, # 2,..., #N of the N types of media or the interrupted sound having the same content is subjected to the limiter process, and the signal quality cannot be maintained.

  Furthermore, in order to reduce the PAPR of the synthesized N types of AM modulation signals, various types of N types of radio voices # 1, # 2,. Delay elements 142-1, 142-2,..., 142 -N that give a delay of a long length are applied. That is, the correlation of radio sounds # 1, # 2,..., #N of N types of media is reduced, and the complete correlation of interrupted voices having the same content is reduced. Therefore, N types of radio sounds # 1, # 2,..., #N or interrupt sounds having the same contents are subjected to delay processing and cannot maintain signal quality. A delay element that gives a sufficiently long delay to sufficiently reduce the correlation with respect to a low-frequency signal such as an audio signal is required.

  Therefore, in order to solve the above-described problem, the present invention provides a technique for combining a plurality of AM modulation signals having different carrier frequencies, while reducing power consumption, maintaining signal quality, and simplifying the device configuration. The object is to reduce the PAPR of the AM modulation signal.

  In order to achieve the above object, the phases of the plurality of AM modulation signals are set in a distributed manner so that the linearity of the input / output characteristics of the amplifier circuit and the like is maintained.

  Specifically, the present invention is an AM modulation signal combining device that combines a plurality of AM modulation signals having different carrier frequencies and outputs the combined plurality of AM modulation signals to a predetermined circuit. The AM modulation signal synthesizing apparatus is characterized in that the phases of the plurality of AM modulation signals are distributed and set so that the linearity of the input / output characteristics is maintained.

  In order to achieve the above object, the phases of a plurality of carrier waves having different frequencies are set in a distributed manner so that the linearity of input / output characteristics of an amplifier circuit or the like is maintained.

  Specifically, the present invention is an AM modulation signal combining apparatus that combines a plurality of AM modulation signals having different carrier frequencies, and outputs the combined AM modulation signals to a predetermined circuit. AM is modulated with a plurality of signals, and the phase of each of the plurality of carriers is distributed and set so that the linearity of the input / output characteristics of the predetermined circuit is maintained. This is a modulation signal synthesizer.

  In order to achieve the above object, the phases of a plurality of signals for modulating a plurality of carriers are set in a distributed manner so that the linearity of input / output characteristics of an amplifier circuit or the like is maintained.

  Specifically, the present invention is an AM modulation signal combining apparatus that combines a plurality of AM modulation signals having different carrier frequencies, and outputs the combined AM modulation signals to a predetermined circuit. AM is modulated with a plurality of signals, and the phase of each of the plurality of signals is distributed and set so that the linearity of the input / output characteristics of the predetermined circuit is maintained. This is a modulation signal synthesizer.

  In order to achieve the above object, the AM modulation signal transmission device includes an AM modulation signal synthesis device, an amplifier circuit, and the like, and amplifies and transmits a plurality of synthesized AM modulation signals.

  Specifically, the present invention includes the AM modulation signal combining device described above and a predetermined circuit, and the predetermined circuit performs predetermined processing on the plurality of AM modulation signals combined by the AM modulation signal combining device. This is an AM modulated signal transmitting apparatus characterized by executing and transmitting in parallel.

  According to these configurations, since it is only necessary to use an amplifier circuit or the like having a low saturation level, power consumption of the amplifier circuit or the like can be reduced. The signal quality can be maintained for a plurality of signals for modulating a plurality of carrier waves because the limiter process is not necessarily executed. Furthermore, since phase dispersion processing is performed without performing delay processing, a plurality of signals for modulating a plurality of carriers can maintain signal quality, and the AM modulation signal synthesizer has a simplified device configuration. Can be In this way, it is possible to reduce the PAPR of a plurality of synthesized AM modulated signals while reducing power consumption, maintaining signal quality, and simplifying the device configuration.

  As described above, according to the present invention, in a technique for combining a plurality of AM modulated signals having different carrier frequencies, the PAPR of the plurality of AM modulated signals combined is achieved while reducing power consumption, maintaining signal quality, and simplifying the device configuration. Can be reduced.

It is a block diagram which shows the structure of the radio rebroadcast apparatus of a prior art. It is a block diagram which shows the structure of the radio rebroadcast apparatus of this invention. It is a block diagram which shows the structure of the radio rebroadcast apparatus of this invention. It is a block diagram which shows the structure of the radio rebroadcast apparatus of this invention.

  Embodiments of the present invention will be described with reference to the accompanying drawings. The embodiments described below are examples of the present invention, and the present invention is not limited to the following embodiments. In the present specification and drawings, the same reference numerals denote the same components.

  2 to 4 are block diagrams showing the configuration of the radio rebroadcast apparatus of the present invention. Normally, N types of carrier waves having different frequencies are AM-modulated with N types of radio sounds # 1, # 2,..., #N, and N types of AM modulated signals are synthesized and amplified. In an emergency, N types of carrier waves having different frequencies are AM-modulated with interrupted speech having the same content, and N types of AM-modulated signals are synthesized and amplified.

  The radio rebroadcast device 1 includes a radio audio receiver 11, an interrupt audio generator 12, an audio distributor 13, an AM modulated signal synthesizer 14, and an AM modulated signal transmitter 15.

  The radio sound receiving apparatus 11 receives N types of radio sounds # 1, # 2,..., #N in the receiving units 111-1, 111-2,. . The interrupt sound generation device 12 generates an interrupt sound having the same content.

  In the distribution unit 131, the sound distribution device 13 inputs radio sound # 1, # 2,..., #N or interrupt sound having the same content of N types of media, and switches 132-1 and 132-2. ,..., 132-N, respectively, output radio sounds # 1, # 2,..., #N of N types of media during normal times, and interrupt sounds with the same content in an emergency. Is output.

  2 modulates and sets the phase of each of the plurality of AM modulation signals so that the linearity of the input / output characteristics of the amplification unit 152 is maintained.

  That is, the modulation units 143-1, 143-2,..., 143-N respectively receive a plurality of carrier waves having different frequencies oscillated by the oscillation units 144-1, 144-2,. In normal times, AM modulation is performed with radio sounds # 1, # 2,..., #N of N types of media, and AM modulation is performed with interrupt sounds having the same contents in an emergency. Next, the phase setting units 146-1, 146-2,..., 146-N have a plurality of carrier frequencies output from the modulation units 143-1, 143-2,. For the AM modulation signal, the (initial) phase is set to be distributed in φ1, φ2,..., ΦN. Next, the synthesizing unit 145 synthesizes a plurality of AM modulated signals in which the (initial) phases output from the phase setting units 146-1, 146-2, ..., 146-N are dispersed.

  3 modulates and sets the phase of each of a plurality of carriers having different frequencies so that the linearity of the input / output characteristics of the amplifier 152 is maintained.

  That is, each of the phase setting units 147-1, 147-2,..., 147-N includes a plurality of carrier waves having different frequencies at which the oscillation units 144-1, 144-2,. Are set in such a manner that the (initial) phase is dispersed in φ1, φ2,..., ΦN. Next, the modulation units 143-1, 143-2,..., 143-N are respectively a plurality of carrier waves having different frequencies oscillated by the oscillation units 144-1, 144-2,. Are normally modulated with radio voices # 1, # 2,..., #N of N types of media, and AM is modulated with interrupted voices having the same contents in an emergency. Next, the synthesizer 145 synthesizes a plurality of AM modulated signals in which the (initial) phases output from the modulators 143-1, 143-2, ..., 143-N are dispersed.

  4 modulates and sets the phase of each of a plurality of signals for modulating a plurality of carriers so that the linearity of the input / output characteristics of the amplifying unit 152 is maintained.

  That is, the phase setting units 148-1, 148-2,..., 148 -N respectively correspond to the N types of media that the switches 132-1, 132-2,. For the radio voices # 1, # 2,..., #N, or interrupt voices of the same content that are output in an emergency, the (initial) phase is set in a distributed manner to φ1, φ2,. Next, the modulation units 143-1, 143-2,..., 143-N are respectively a plurality of carrier waves having different frequencies oscillated by the oscillation units 144-1, 144-2,. Are normally modulated with radio voices # 1, # 2,..., #N of N types of media, and AM is modulated with interrupted voices having the same contents in an emergency. Next, the synthesizer 145 synthesizes a plurality of AM modulated signals in which the (initial) phases output from the modulators 143-1, 143-2, ..., 143-N are dispersed.

  2 to 4, by applying an NCO (Numerically Controlled Oscillator) that performs digital signal processing as the oscillators 144-1, 144-2, ..., 144-N, Phase control can be easily performed, and the control characteristics can be stabilized.

  2 to 4, the (initial) phase combinations (φ1, φ2,..., ΦN) may be the same or different in normal and emergency situations.

  When the combination of (initial) phases (φ1, φ2,..., ΦN) is different between the normal time and the emergency time, in normal time, radio sound # 1, # 2,. If the correlation of #N is low, the (initial) phase variance does not have to be increased. In an emergency, since the correlation of audio signals having the same content is high, the (initial) phase variance is increased. It is desirable.

  The (initial) phase combinations (φ1, φ2,..., ΦN) may be set according to predictions and evaluations based on statistical results as long as the linearity of the input / output characteristics of the amplification unit 152 is maintained. Well, it may be set according to predictions and evaluations based on simulation, may be set by adjustment on site (in a closed space such as in a tunnel), and it is tried and selected from multiple patterns even if it is not set to the optimum value The approximate value may be set.

  In the AM modulation signal transmission device 15, the amplification unit 152 amplifies the combined AM modulation signal, and the transmission unit 153 transmits the amplified AM modulation signal.

  According to this embodiment, since it is sufficient to use the amplification unit 152 having a low saturation level, the power consumption of the amplification unit 152 can be reduced. Since a plurality of signals for modulating a plurality of carrier waves (N types of radio sounds # 1, # 2,..., #N or audio signals having the same contents) are not necessarily subjected to limiter processing. Signal quality can be maintained. Further, since the phase dispersion process is performed without performing the delay process, a plurality of signals for modulating a plurality of carriers (radio sounds # 1, # 2,. Audio signal) can maintain the signal quality, and the AM modulation signal synthesizer 14 can simplify the device configuration. In this way, it is possible to reduce the PAPR of a plurality of synthesized AM modulated signals while reducing power consumption, maintaining signal quality, and simplifying the device configuration.

  In this embodiment, the AM modulation signal synthesis device 14 is applied to the radio rebroadcast device 1. Here, as a general modification, the AM modulation signal combining device 14 may be applied to a technique for combining a plurality of AM modulation signals having different carrier frequencies.

  In the present embodiment, a plurality of AM modulated signals having different carrier frequencies are phase-dispersed so that the linearity of the input / output characteristics of the amplifying unit 152 is maintained. Here, as a general modification, a plurality of AM modulation signals having different carrier frequencies may be phase-dispersed so that the linearity of input / output characteristics of a desired circuit including the amplification unit 152 is maintained.

  The AM modulation signal synthesizing apparatus and AM modulation signal transmitting apparatus of the present invention can be applied to a technique for synthesizing and transmitting a plurality of AM modulation signals having different carrier frequencies.

1: Radio rebroadcast device 11: Radio audio receiver 12: Interrupt audio generator 13: Audio distributor 14: AM modulated signal synthesizer 15: AM modulated signal transmitters 111-1, 111-2, 111-N: Receiver 131: Distributors 132-1, 132-2, 132-N: Switches 141-1, 141-2, 141-N: Limiters 142-1, 142-2, 142-N: Delay elements 143-1 143-2, 143-N: Modulation units 144-1, 144-2, 144-N: Oscillation unit 145: Synthesis units 146-1, 146-2, 146-N: Phase setting units 147-1, 147-2 147-N: phase setting unit 148-1, 148-2, 148-N: phase setting unit 151: CFR limiter 152: amplification unit 153: transmission unit

Claims (4)

An AM modulation signal combining device that combines a plurality of AM modulation signals having different carrier frequencies and outputs the combined AM modulation signals to a predetermined circuit,
An AM modulation signal synthesizing apparatus, wherein the phase of each of the plurality of AM modulation signals is set in a distributed manner so that the linearity of the input / output characteristics of the predetermined circuit is maintained. An AM modulation signal combining device that combines a plurality of AM modulation signals having different carrier frequencies and outputs the combined AM modulation signals to a predetermined circuit,
AM-modulate a plurality of carrier waves having different frequencies with a plurality of signals,
An AM-modulated signal synthesizer, wherein the phase of each of the plurality of carriers is set in a distributed manner so that the linearity of the input / output characteristics of the predetermined circuit is maintained. An AM modulation signal combining device that combines a plurality of AM modulation signals having different carrier frequencies and outputs the combined AM modulation signals to a predetermined circuit,
AM-modulate a plurality of carrier waves having different frequencies with a plurality of signals,
An AM-modulated signal synthesizer, wherein the phase of each of the plurality of signals is distributed and set so that the linearity of the input / output characteristics of the predetermined circuit is maintained. An AM modulation signal synthesizer according to any one of claims 1 to 3 and a predetermined circuit,
An AM-modulated signal transmitting apparatus that performs a predetermined process in the predetermined circuit and transmits the plurality of AM-modulated signals combined by the AM-modulated signal combining apparatus in parallel.

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