JP2017199971A - Transmission system and antenna system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique capable of transmitting a control signal on a signal transmission path for transmitting output of a ΔΣ modulator.SOLUTION: A transmission system includes: a signal processing device 2 for transmitting a ΔΣ modulation signal obtained by applying ΔΣ modulation to a transmission signal; a radio device 3 for receiving the ΔΣ modulation signal; and a signal cable 4 on which the ΔΣ modulation signal is transmitted between the signal processing device 2 and the radio device 3. The signal processing device 2 gives a control signal on control of the radio device 3 to the signal cable 4, and thereby transmits the control signal through the signal cable 4 to the radio device 3. Quantization noise of the ΔΣ modulation signal is suppressed at a frequency of the control signal.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a transmission system and an antenna system using the transmission system.

  Conventionally, a signal obtained by performing ΔΣ modulation on an analog transmission signal is wirelessly transmitted (see, for example, Patent Document 1).

FIG. 10 is a diagram illustrating an example of a communication system including a ΔΣ modulator. As shown in FIG. 10, the communication system 100 includes a signal processing unit 101 that outputs a transmission signal that is an RF signal, a ΔΣ modulator (DSM) 102 to which the transmission signal is given, and a bandpass filter 103. Yes.
The ΔΣ modulator 102 performs ΔΣ modulation on the transmission signal and outputs a ΔΣ modulation signal. The ΔΣ modulation signal is given to the band pass filter 103 through the signal transmission path 104.
The band pass filter 103 has a pass band that allows the transmission signal to pass therethrough. Therefore, the bandpass filter 103 removes the quantization noise contained in the ΔΣ modulation signal while allowing the transmission signal to pass. As a result, the bandpass filter 103 outputs a transmission signal.
The transmission signal output from the band pass filter 103 is amplified by the power amplifier 105 at the subsequent stage and transmitted as a radio wave from the antenna 106.

  In the communication system 100 of FIG. 10, a transmission signal can be transmitted as a ΔΣ modulation signal which is a digital signal (pulse signal) between the ΔΣ modulator 102 and the bandpass filter 103. For this reason, even if the signal transmission path 104 connecting the ΔΣ modulator 102 and the bandpass filter 103 is made relatively long, signal attenuation can be suppressed.

Therefore, the signal processing unit 101 and the ΔΣ modulator 102 are unitized as the signal processing device 110, and the bandpass filter 103, the power amplifier 105, and the antenna 106 are unitized as the radio device 111, and these are mutually connected by the signal transmission path 104. If connected, the signal processing device 110 and the wireless device 111 can be arranged at different positions, and the degree of freedom of the installation mode of the communication system 100 can be ensured.
That is, the signal processing device 110 and the wireless device 111 constitute a transmission system that transmits the ΔΣ modulation signal output from the ΔΣ modulator via the signal transmission path 104.

Japanese Patent No. 5598561

  In the above system that transmits a ΔΣ modulation signal, if the control signal for controlling the wireless device 111 can be transmitted from the signal processing device 110 to the wireless device 111, the controllability of the wireless device 111 can be improved. it can.

Here, it is conceivable to transmit the control signal using the signal transmission path 104 that connects the signal processing device 110 and the wireless device 111.
However, the delta-sigma modulated signal output from the delta-sigma modulator 102 is noise-shaped and suppressed in the band containing the transmission signal as the main signal component, but is quantized over a wide band in other areas. It contains noise.
Therefore, if the control signal is transmitted using the signal transmission path 104 to which the ΔΣ modulation signal output from the ΔΣ modulator 102 is applied, the control signal is superimposed on the quantization noise of the ΔΣ modulation signal, and the control signal is transmitted. It has been difficult to transmit signals with appropriate signal quality.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a technique capable of transmitting a control signal to a signal transmission path for transmitting a ΔΣ modulation signal.

  A transmission system according to an embodiment is a transmission system that transmits a ΔΣ-modulated signal that is ΔΣ-modulated with respect to a communication signal, the receiver that receives the ΔΣ-modulated signal, and the ΔΣ-modulated signal that is transmitted as a signal A transmitting device that transmits to the receiving device via a path, and at least one of the transmitting device and the receiving device provides the signal transmission path with a control signal related to the control of the transmitting device or the receiving device. The control signal is transmitted to the other of the transmission device and the reception device, and the ΔΣ modulation signal is suppressed in quantization noise at the frequency of the control signal.

  In addition, an antenna system according to an embodiment is an antenna system including the transmission system, and the reception device transmits the communication signal obtained from one or a plurality of antenna elements and the ΔΣ modulation signal to the 1 or 1 One or a plurality of transmitters that transmit to a plurality of antenna elements and wirelessly transmit, and the control signal includes a signal related to the control of the one or a plurality of transmitters, the one or a plurality of transmitters, Radio transmission is performed based on the control information transmitted from the transmission device.

  According to the present invention, it is possible to transmit the control signal to the signal transmission path for transmitting the ΔΣ modulation signal.

It is a block diagram which shows the structure of the communication system by 1st Embodiment. It is a block diagram which shows an example of the delta-sigma modulator of this embodiment. It is a figure which shows an example of the power spectrum of the output by the delta-sigma modulator of this embodiment. It is an enlarged view of a portion of the band B ₂ at the output of the first band elimination filter. It is a block diagram which shows the structure of the communication system by 2nd Embodiment. It is a figure which shows the structure of the communication system by 3rd Embodiment. It is a figure which shows the structure of the radio | wireless apparatus which concerns on the modification of 3rd Embodiment. It is a figure which shows the structure of the radio | wireless apparatus which concerns on the other modification of 3rd Embodiment. In FIG. 8, it is a figure which shows the structure of a radio | wireless part. It is a figure which shows an example of the communication system provided with the delta-sigma modulator.

[Description of Embodiment]
First, the contents of the embodiment will be listed and described.
(1) A transmission system according to an embodiment is a transmission system that transmits a ΔΣ-modulated signal that is ΔΣ-modulated with respect to a communication signal, the receiver that receives the ΔΣ-modulated signal, and the ΔΣ-modulated signal. A transmitting device that transmits to the receiving device via a signal transmission path, and at least one of the transmitting device and the receiving device transmits a control signal related to control of the transmitting device or the receiving device to the signal transmission path. The control signal is transmitted to the other of the transmission device and the reception device, and quantization noise is suppressed in the ΔΣ modulation signal at the frequency of the control signal.

  According to the transmission system having the above configuration, it is possible to suppress the control signal applied to the signal transmission path by at least one of the transmission device and the reception device from being superimposed on the quantization noise of the ΔΣ modulation signal. For this reason, it is possible to transmit the control signal to the signal transmission path for transmitting the ΔΣ modulation signal to the wireless device.

(2) In the transmission system, the transmission device includes a ΔΣ modulator that performs ΔΣ modulation on the communication signal, and the ΔΣ modulator blocks quantization noise in a first frequency band including the frequency of the communication signal. In addition, it may have a characteristic of blocking quantization noise in the second frequency band including the frequency of the control signal.
In this case, the frequency of the communication signal and the frequency of the control signal can be set differently, and the communication signal and the control signal can be multiplexed and transmitted.

(3) In the transmission system of (2), the transmission device includes a band rejection filter having a signal rejection band including the output of the ΔΣ modulator and including a frequency of the control signal. Is preferably output as the ΔΣ modulation signal.
(4) In the transmission system according to (1), the transmission device includes a ΔΣ modulator that performs ΔΣ modulation on the communication signal, and a signal that includes the output of the ΔΣ modulator and includes the frequency of the control signal. A band elimination filter having a elimination band, and outputting an output of the band elimination filter as the ΔΣ modulation signal.

(5) In the transmission system, it is preferable that the transmission device includes a control signal extraction unit that extracts the control signal transmitted from the reception device from a signal transmitted to the signal transmission path.
(6) Moreover, it is preferable that the said receiving apparatus is provided with the control signal extraction part which extracts the said control signal which the said transmitter transmitted from the signal transmitted to the said signal transmission path.
Thereby, the transmission device and the reception device can acquire the control signal.

(7) In the transmission system, it is preferable that the reception device includes a binarizer that binarizes the ΔΣ modulation signal given through the signal transmission path.
In this case, even if the ΔΣ modulation signal supplied to the receiving device is transmitted through the signal transmission path, it is attenuated by binarizing the ΔΣ modulation signal that is a binary pulse signal by the binarizer. It is possible to obtain a ΔΣ modulation signal in which the influence of the above is mitigated.

(8) Moreover, the antenna system which is one Embodiment is an antenna system provided with the transmission system as described in said (1), Comprising: The said receiving device is based on the 1 or several antenna element, and the said (DELTA) Σ modulation signal. One or a plurality of transmitters that wirelessly transmit the communication signal obtained to the one or a plurality of antenna elements, and the control signal includes a signal related to the control of the one or a plurality of transmitters, One or a plurality of transmission units wirelessly transmit based on the control information transmitted from the transmission device.

  According to the antenna system configured as described above, it is possible to transmit a signal related to the control of the transmission unit to the signal transmission path for transmitting the ΔΣ modulation signal to the reception apparatus, and to transmit without providing a new signal path. Part can be controlled.

(9) In the antenna system, the reception device includes a distribution unit that distributes the ΔΣ modulation signal to the plurality of transmission units, and the control signal includes a signal related to control of the distribution unit. May be.
In this case, a signal related to the control of the distribution unit can be transmitted to the signal transmission path, and the distribution unit can be controlled without providing a new signal path.

[Details of the embodiment]
Hereinafter, preferred embodiments will be described with reference to the drawings.
Note that at least a part of each embodiment described below may be arbitrarily combined.
[About the first embodiment]
FIG. 1 is a block diagram showing a configuration of a communication system according to the first embodiment.
The communication system 1 is a system for performing wireless communication, and includes a signal processing device 2 and a wireless device 3.

The wireless device 3 has a function of transmitting and receiving wireless signals.
The signal processing device 2 gives a transmission signal to the wireless device 3.
The wireless device 3 and the signal processing device 2 are connected to each other by a signal cable 4 as a signal transmission path. The signal processing device 2 gives a transmission signal and a control signal related to control of the wireless device 3 to the wireless device 3 via the signal cable 4.

  Here, as will be described later, the signal processing device 2 functions as a transmission device that transmits a ΔΣ modulation signal that is a digital signal (pulse signal) obtained by performing ΔΣ modulation on a transmission signal (communication signal). And the wireless device 3 has a function as a receiving device for receiving the ΔΣ modulation signal. Further, the signal cable 4 has a function as a signal transmission path through which a ΔΣ modulation signal is transmitted between the signal processing device 2 and the wireless device 3. That is, the signal processing device 2, the wireless device 3, and the signal cable 4 constitute a transmission system that transmits a ΔΣ modulated signal that is ΔΣ modulated with respect to a transmission signal (communication signal).

  Further, the control signal is a signal related to control of the wireless device 3 or the signal processing device 2, a signal for controlling a functional unit included in the wireless device 3, information indicating an operation state or an environmental state of the wireless device 3, A signal including information necessary for controlling the wireless device 3 or the signal processing device 2 such as a signal for controlling a functional unit included in the signal processing device 2 and information indicating an operation state or an environmental state of the signal processing device 2 Etc.

The signal processing device 2 includes an orthogonal modulation unit 10, a modulation device 9, and an adder 13.
The quadrature modulation unit 10 performs quadrature modulation on a digital baseband signal (I (In-phase) signal and Q (Quadrature-phase) signal) and up-converts it to a radio frequency. The quadrature modulation unit 10 outputs an RF signal (Radio Frequency signal) that is a radio frequency signal. The RF signal output from the quadrature modulation unit 10 is a transmission signal that is wirelessly transmitted by the wireless device 3.
The RF signal (transmission signal) output from the quadrature modulation unit 10 is given to the modulation device 9.

  The modulation device 9 performs ΔΣ modulation on the transmission signal output from the quadrature modulation unit 10 and outputs a ΔΣ modulation signal. The modulation device 9 includes a ΔΣ modulator (DSM) 11 and a first band elimination filter 12.

The ΔΣ modulator 11 performs ΔΣ modulation on the transmission signal output from the quadrature modulation unit 10 and outputs a ΔΣ modulation signal including the transmission signal as a frequency component. The ΔΣ modulation signal output from the ΔΣ modulator 11 is a digital signal (pulse signal).
Here, the delta-sigma modulator 11 in this embodiment is comprised by the multicarrier type | mold delta-sigma modulator which can input a signal from two input ports.

FIG. 2 is a block diagram illustrating an example of the ΔΣ modulator 11 of the present embodiment.
The ΔΣ modulator 11 includes a first input port 16 to which the first signal U ₁ is input, a second input port 17 to which the second signal U ₂ is input, and a single output port 18 that outputs the ΔΣ modulation signal. I have. The ΔΣ modulator 11 includes a plurality of loop filters (first loop filter 19 and second loop filter 20) corresponding to each of the plurality of input ports 16 and 17, an adder 21, and a quantizer 22. Yes.
The plurality of loop filters 19 and 20 are connected to the output side of the quantizer 22 via the first input sections 19a and 20a connected to the corresponding input ports 16 and 17 and the feedback paths 23 and 24, respectively. 2nd input part 19b, 20b.

Input signals U ₁ and U ₂ input to corresponding input ports 16 and 17 are input to the first input sections 19a and 20a. The feedback signal V of the output V of the quantizer 22 is input to the second input units 19b and 20b.

The plurality of loop filters 19 and 20 include differentiators 19c and 20c, respectively. Connected to the differentiators 19c and 20c are first paths 19d and 20d connected to the first input sections 19a and 20a and second paths 19e and 20e connected to the second input sections 19b and 20b, respectively. Has been. The differentiators 19c and 20c obtain differences U ₁ −V and U ₂ −V between the input signals U ₁ and U ₂ and the feedback signal V from the quantizer 22, respectively.

Differences U ₁ −V and U ₂ −V obtained by the differentiators 19c and 20c are input to internal filters 19f and 20f provided in the loop filters 19 and 20, respectively. The transfer function of the internal filter 19f of the first loop filter 19 is expressed as L ₁ (z), and the transfer function of the internal filter 20f of the second loop filter 20 is expressed as L ₂ (z).

The outputs L ₁ (z) (U ₁ (z) −V (z)) and L ₂ (z) (U ₂ (z) −V (z)) of the internal filters 19 f and 20 f 20 is provided to adders 19g and 20g.
Feed forward paths 19h and 20h for inputting the input signals U ₁ and U ₂ input to the first input units 19a and 20a to the adders 19g and 20g are connected to the adders 19g and 20g, respectively. Accordingly, the adders 19g and 20g are connected to the input signals U ₁ and U ₂ and the outputs L ₁ (z) (U ₁ (z) −V (z)) and L ₂ (z) ( U ₂ (z) −V (z)) is added.

Outputs of the adders 19g and 20g (outputs of the loop filters 19 and 20) Y ₁ and Y ₂ are added by the adder 21.

  The output Y of the adder 21 is given to the quantizer 22. The quantizer 22 of this embodiment is a two-level quantizer, and outputs a 1-bit pulse train as a quantized signal (ΔΣ modulation signal) V. This quantized signal V becomes an output signal of the ΔΣ modulator 11. The output signal V is given to the loop filters 19 and 20 via the feedback paths 23 and 24.

The output V of the ΔΣ modulator 11 is expressed by the following equation (1) (when N = 2 in equation (1)). In Equation (1), STF _i (z) is the i-th signal transfer function for the i-th input signal U _i (z), and NTF (z) is the noise transfer function for the entire ΔΣ modulator 11. E (z) is a noise transfer function.
here,

The internal filter 19f of the first loop filter 19 has a transfer function L ₁ (z) indicated by using the first noise transfer function NTF ₁ (z). The first noise transfer function NTF ₁ (z) is set to have a characteristic (band stop characteristic) that suppresses quantization noise in a band near the frequency of the first signal U ₁ input to the first loop filter 19. The That is, the center frequency of the band (quantization noise stop band) in which the quantization noise in the first noise transfer function NTF ₁ (z) can be suppressed is the frequency of the first signal U ₁ .

The internal filter 20f of the second loop filter 20 has a transfer function L ₂ (z) indicated by using the second noise transfer function NTF ₂ (z). The second noise transfer function NTF ₂ (z) is set to have a characteristic (band stop characteristic) for suppressing quantization noise in a band near the frequency of the second signal U ₂ input to the second loop filter 20. The That is, the center frequency of the quantization noise stop band in the second noise transfer function NTF ₂ (z) is the frequency of the second signal U ₂ .

The ΔΣ modulator 11 having the above configuration simultaneously converts the first signal U ₁ input to the first input port 16 and the second signal U ₂ input to the second input port 17 into a single output signal V ( z) that is included in the ΔΣ modulation signal.

In the present embodiment, as will be described later, a transmission signal output from the quadrature modulation unit 10 as the first signal U ₁ is given to the ΔΣ modulator 11. For this reason, the first noise transfer function NTF ₁ (z) of the first loop filter 19 is set so that the center frequency of the quantization noise stop band becomes the frequency f _{1 of the} transmission signal.

On the other hand, the signal as the second signal U ₂ is not input to the ΔΣ modulator 11. However, the second noise transfer function NTF ₂ (z) of the second loop filter 20 is a frequency whose center frequency of the quantization noise stop band is different from the frequency f _{1 of the} transmission signal, and the frequency f _{2 of the} control signal described later. Is set to be

FIG. 3 is a diagram illustrating an example of a power spectrum of the output by the ΔΣ modulator 11 of the present embodiment.
As shown in FIG. 3, the output from the ΔΣ modulator 11 (ΔΣ modulation signal) is a band B ₁ having a transmission signal frequency f ₁ as a center frequency and a control signal frequency f ₂ having a center frequency B _2. , The quantization noise is suppressed (noise shaping). Band B ₁ and band B ₂ are different frequency bands.

As described above, the center frequency of the quantization noise stop band in the first noise transfer function NTF ₁ (z) is set to be the frequency f _{1 of the} transmission signal. The center frequency of the quantization noise stop band in the second noise transfer function NTF ₂ (z) is set to be the frequency f _{2 of the} control signal.

Therefore, as shown in FIG. 3, .DELTA..SIGMA modulator output by 11, second band B ₂ having a center frequency f ₂ of the band B _1, and the reception signal to a center frequency f ₁ of the transmission signal A band where the quantization noise is suppressed appears at the location.

Thus, .DELTA..SIGMA modulator 11 is configured to prevent the quantization noise of the band B ₁ includes a frequency f ₁ of the transmission signal _(first frequency band), band B ₂ including the frequency f ₂ of the received signal _(second (Frequency band) to prevent quantization noise.

The output by the ΔΣ modulator 11 has a transmission signal in a band B _1. On the other hand, since the signal of the second signal U ₂ in band B ₂ is not input to the ΔΣ modulator 11, output by the ΔΣ modulator 11 has no signal in the band B _2.

Returning to FIG. 1, the transmission signal output from the quadrature modulation unit 10 is given to the first input port 16 of the ΔΣ modulator 11. On the other hand, nothing is input to the second input port 17 of the ΔΣ modulator 11.
The ΔΣ modulator 11 outputs a ΔΣ modulation signal from the output port 18.
The ΔΣ modulation signal output from the ΔΣ modulator 11 is given to the first band elimination filter 12.

The first band elimination filter 12 is connected between the ΔΣ modulator 11 and the signal cable 4, and is connected between the ΔΣ modulator 11 and the adder 13, and includes a signal including the frequency f _{2 of the} control signal. It has a removal band. For example, the signal removal band of the first band elimination filter 12 of the present embodiment is set to a frequency band including the band B ₂ as the frequency band including the frequency f _{2 of the} control signal.
Thus, the first band elimination filter 12, the ΔΣ modulated signal from the ΔΣ modulator 11 is given, among the ΔΣ modulated signal to remove quantization noise in the band B _2.

Figure 4 is an enlarged view of a portion of the band B ₂ at the output of the first band elimination filter 12.
In FIG. 4, the broken line H indicates the noise profile of the band B ₂ in the ΔΣ modulation signal output from the ΔΣ modulator 11. A solid line J indicates a noise profile of the band B ₂ in the ΔΣ modulation signal after passing through the first band elimination filter 12.

The quantization noise of the band B ₂ is suppressed as compared with the quantization noise of other bands, but still exists to the extent that it can be further suppressed.
Therefore, .DELTA..SIGMA modulated signal outputted from the .DELTA..SIGMA modulator 11, passes through the first band elimination filter 12, as shown in FIG. 4, the level of quantization noise in the band B ₂ from a broken line H to the solid line J descend.
Thus, the first band elimination filter 12 can further reduce the level of the quantization noise in the band B _{2 where} the quantization noise is suppressed in the ΔΣ modulation signal.

  Returning to FIG. 1, as described above, the modulation device 9 has a ΔΣ modulator 11 that performs ΔΣ modulation on a transmission signal, and a signal removal band that includes the output of the ΔΣ modulator 11 and includes the frequency of the control signal. A first band elimination filter 12 is provided. The modulation device 9 outputs a ΔΣ modulation signal after passing through the first band elimination filter 12.

The ΔΣ modulation signal that has passed through the first band elimination filter 12 is supplied to the adder 13.
The adder 13 is given a control signal generated by the control signal generator 30.
Control signal generating unit 30 generates a control signal of frequency f _2. The control signal generated by the control signal generation unit 30 includes information necessary for controlling the wireless transmission unit 46 (described later) included in the wireless device 3.
Control signal generating unit 30, by modulating a carrier wave of frequency f _2, and generates a control signal including information necessary for controlling the radio transmission section 46. The control signal generated by the control signal generation unit 30 is an analog signal.

A first band pass filter 31 is connected between the control signal generator 30 and the adder 13. The first band pass filter 31 is set so that the signal pass band includes the frequency f _{2 of the} control signal and prevents the transmission signal from passing.
Therefore, when the control signal is supplied from the control signal generation unit 30, the first band pass filter 31 passes the control signal and supplies the control signal to the adder 13.

The adder 13 adds the ΔΣ modulation signal output from the modulation device 9 and the control signal output from the control signal generation unit 30.
A signal obtained by adding the ΔΣ modulation signal and the control signal, which is the output of the adder 13, is given to the signal cable 4 through the connector 33.
In this way, the signal processing device 2 gives the signal cable 4 the ΔΣ modulation signal output from the first band elimination filter 12.

The connector 33 is exposed outside the housing 34 of the signal processing device 2. The connector 33 connects the signal cable 4 and the adder 13 by inserting one end of the signal cable 4.
The housing 34 of the signal processing device 2 accommodates the quadrature modulation unit 10, the modulation device 9, the adder 13, and the like inside.

  The other end of the signal cable 4 is connected to the wireless device 3. The output of the adder 13 is transmitted to the wireless device 3 via the signal cable 4.

Here, the ΔΣ modulation signal output from the ΔΣ modulator 11 (modulation device 9) includes quantization noise over a wide band as shown in FIG.
For this reason, the control signal added to the ΔΣ modulation signal by the adder 13 may be superposed on the quantization noise included in the ΔΣ modulation signal.

In this regard, in the present embodiment, the ΔΣ modulation signal output from the ΔΣ modulator 11 (modulation device 9) has a quantization noise (in the band B ₂ including the control signal frequency f ₂ ) at the frequency f ₂ of the control signal. It is suppressed (see FIG. 3).
For this reason, if a control signal having the frequency f ₂ is applied to the signal cable 4, it is possible to suppress the control signal from being superimposed on the quantization noise of the ΔΣ modulation signal. Thereby, the control signal can be transmitted to the signal cable 4 for transmitting the ΔΣ modulation signal by the modulation device 9.

Since ΔΣ modulator 11 of the present embodiment is a multi-carrier type ΔΣ modulator capable of inputting signals from the two input ports, one for inputting a transmission signal as a first signal U _1, second signal U _By not inputting a signal as ₂ , a band B _{2 in} which quantization noise is suppressed but there is no signal component to be output can be provided in the ΔΣ modulation signal.

In the present embodiment, a band B ₂ in which quantization noise is suppressed is provided in a part of the band of the ΔΣ modulation signal. By using this band B ₂ for signal transmission in the signal cable 4, The control signal can be transmitted by the cable 4.
As a result, it is possible to multiplex and transmit the ΔΣ modulation signal that is a digital signal and the control signal that is an analog signal using the signal cable 4 that is one transmission line.

Furthermore, in this embodiment, as shown in FIG. 4, the first band elimination filter 12 included in the modulation device 9 suppresses quantization noise in the ΔΣ modulation signal output from the ΔΣ modulator 11. Since the level of the quantization noise in the band B ₂ which is the band is further reduced, the signal quality such as the signal-to-noise ratio of the control signal of the frequency f ₂ transmitted through the signal cable 4 can be further increased.

  As described above, in the present embodiment, a ΔΣ modulation signal is transmitted between the signal processing device 2 constituting the transmission system that transmits the ΔΣ modulated signal that is ΔΣ modulated with respect to the transmission signal, and the wireless device 3. A control signal that is an analog signal can be appropriately transmitted with high signal quality while being transmitted.

The other end of the signal cable 4 is connected to the connector 44 of the wireless device 3.
The wireless device 3 includes a second band elimination filter 40, a binarizer 41, a second band pass filter 42, and a control signal extraction unit 43.

  The output of the adder 13 given to the signal cable 4 is given to the second band elimination filter 40 and the control signal extraction unit 43 through the connector 44.

The connector 44 is provided so as to be exposed outside the housing 45 of the wireless device 3. The connector 44 connects the signal cable 4 to the second band elimination filter 40 and the control signal extraction unit 43 by inserting the other end of the signal cable 4.
As described above, the signal cable 4 connects the signal processing device 2 and the wireless device 3, and transmits the output of the adder 13 to the wireless device 3.

  Note that the housing 45 of the wireless device 3 includes the second band elimination filter 40, the binarizer 41, the second bandpass filter 42, the control signal extraction unit 43, and other functions included in the wireless device 3 described later. The part is housed inside.

Similar to the first band elimination filter 12, the second band elimination filter 40 has a signal removal band including the band B ₂ (FIGS. 3 and 4) as a frequency band including the frequency f _{2 of the} control signal. .
The output of the adder 13 is obtained by adding the ΔΣ modulation signal from the modulation device 9 and the control signal from the control signal generator 30. Thus, the second band elimination filter 40, the output of the adder 13 is given, among the output, removing the control signal included in the band B _2.
As a result, it is possible to prevent the influence due to the control signal from occurring in the processing subsequent to the second band elimination filter 40.

When the output of the adder 13 is given, the second band elimination filter 40 removes the control signal from the output of the adder 13 and outputs a ΔΣ modulation signal from the modulation device 9.
The ΔΣ modulation signal output from the second band elimination filter 40 is supplied to the binarizer 41.
The binarizer 41 is constituted by a comparator or the like, binarizes the ΔΣ modulation signal given by transmitting the signal cable 4 from the signal processing device 2, and outputs a binarized ΔΣ modulation signal.

  The ΔΣ modulation signal transmitted through the signal cable 4 and applied to the wireless device 3 is attenuated while being transmitted as compared to when it is output from the modulation device 9. The binarizer 41 binarizes the attenuated ΔΣ modulation signal. Even for an attenuated ΔΣ modulation signal, the ΔΣ modulation signal that is a binary pulse signal is binarized to restore the ΔΣ modulation signal before attenuation. As a result, the binarizer 41 can output a ΔΣ modulation signal that approximates the ΔΣ modulation signal before attenuation, and can obtain a ΔΣ modulation signal in which the influence of attenuation is mitigated.

The ΔΣ modulation signal output from the binarizer 41 is given to the second band pass filter 42.
The second band pass filter 42 has a pass band that allows transmission signals that are RF signals to pass through. Thereby, the second band pass filter 42 can remove the quantization noise existing outside the band of the transmission signal in the ΔΣ modulation signal and pass the transmission signal.
Therefore, the second band pass filter 42 to which the ΔΣ modulation signal is given outputs a transmission signal.

An output terminal 50 is connected between the binarizer 41 and the second band pass filter 42. The output terminal 50 is provided exposed from the outside of the housing 45. A ΔΣ modulation signal output from the binarizer 41 is supplied to the output terminal 50. The output terminal 50 outputs a ΔΣ modulation signal output from the binarizer 41.
Therefore, by connecting a device for measuring a signal to the output terminal 50 and measuring the output signal, the ΔΣ modulation signal output from the binarizer 41 can be confirmed. Thereby, it is possible to confirm whether or not the ΔΣ modulation signal from the signal processing device 2 is normally transmitted to the wireless device 3.

The output of the second band pass filter 42 is given to the wireless transmission unit 46 connected to the subsequent stage of the second band pass filter 42.
The wireless transmission unit 46 includes a phase shifter that performs phase adjustment on a transmission signal that is an RF signal output from the second bandpass filter 42, an amplitude adjuster that performs amplitude adjustment, and a power amplifier that amplifies the transmission signal. And has a function of adjusting and amplifying the phase and amplitude of a given transmission signal.

The transmission signal output from the second band-pass filter 42 is given to the wireless transmission unit 46 so that the phase and amplitude are adjusted and amplified, and the antenna 48 (antenna element) connected to the subsequent stage of the wireless transmission unit 46 is amplified. ).
The transmission signal given to the antenna 48 is radiated and transmitted to the space as a radio signal.

When the output of the adder 13 is given through the signal cable 4, the control signal extraction unit 43 extracts a control signal from the output of the adder 13.
The control signal extraction unit 43 includes a band pass filter 43a and a signal processing unit 43b.

The band pass filter 43a has a pass band that allows the control signal to pass therethrough. Thereby, the band pass filter 43a can remove the quantization noise existing outside the band of the control signal in the ΔΣ modulation signal. Therefore, the band pass filter 43a outputs a control signal when the output of the adder 13 is given.
The control signal output from the band pass filter 43a is given to the signal processing unit 43b, and after being subjected to signal processing such as demodulation and amplification by the signal processing unit 43b, it is given to the wireless transmission unit 46.

As described above, when the output of the adder 13 is given, the control signal extraction unit 43 extracts the control signal from the output of the adder 13 and gives the extracted control signal to the wireless transmission unit 46.
The control signal is a signal for controlling the wireless transmission unit 46, and includes information related to wireless transmission settings such as the phase, amplitude, and amplification factor of the transmission signal as information necessary for controlling the wireless transmission unit 46. It is out.
When the control signal is given, the wireless transmission unit 46 performs settings related to the wireless transmission of the transmission signal based on the information included in the control signal.

In the communication system 1 (antenna system) of the present embodiment, the wireless device 3 includes an antenna 48 and a wireless transmission unit 46 that wirelessly transmits the transmission signal obtained from the ΔΣ modulation signal to the antenna 48. The transmission unit 46 is configured to wirelessly transmit based on the control information transmitted from the signal processing device 2.
According to this configuration, the signal cable 4 for transmitting the ΔΣ modulation signal to the wireless device 3 can transmit a signal related to the control of the wireless transmission unit 46, and the signal can be transmitted without providing a new signal path. Control regarding the wireless transmission unit 46 can be performed from the processing device 2 side.

In the present embodiment, the modulation device 9 includes a ΔΣ modulator 11 and a first band elimination filter 12 to which the output of the ΔΣ modulator 11 is given, and the signal of the first band elimination filter 12 removal band is set to be a frequency band including the frequency f ₂ of the control signal.
Therefore, for example, when the first band elimination filter 12 can suppress the quantization noise to such an extent that the signal quality necessary for the control signal can be ensured, the ΔΣ modulation signal output from the ΔΣ modulator 11 includes without suppressing quantization noise in a band including the frequency f _2, only the first band elimination filter 12, the quantization noise present in the frequency f ₂ of the control signal may be suppressed.
Even in this case, the ΔΣ modulation signal in which the quantization noise existing at the frequency f ₂ of the control signal is suppressed can be output to the modulation device 9.

Conversely, the ΔΣ modulation signal in which the quantization noise in the band including the frequency f ₂ of the control signal is suppressed is output to the ΔΣ modulator 11 so that the signal quality necessary for the control signal can be ensured. If noise can be suppressed, the output of the ΔΣ modulator 11 may be given to the signal cable 4 without going through the first band elimination filter 12.

However, as in this embodiment, the ΔΣ modulation signal in which the quantization noise existing at the frequency f ₂ of the control signal is suppressed is output to the ΔΣ modulator 11 and the ΔΣ modulation signal is supplied to the first band elimination filter 12. With the configuration, as described above, the level of the quantization noise in the band B _{2 at} the output of the modulation device 9 is further reduced, and the signal quality such as the signal-to-noise ratio of the control signal transmitted to the signal cable 4 is further improved. Can be increased.

  Further, as shown in FIG. 3, the output of the ΔΣ modulator 11 has a sharp boundary between a band in which the quantization noise is suppressed and a band in which the quantization noise is not suppressed. Therefore, if the ΔΣ modulator 11 and the first band elimination filter 12 are combined, even if the filter characteristics of the first band elimination filter 12 are relatively slow, the band in which the quantization noise is suppressed. And the characteristic of the boundary with the band where the quantization noise is not suppressed is not deteriorated, and a large allowable range of the filter characteristic of the first band elimination filter 12 can be secured.

Further, the quantization noise stop band of the ΔΣ modulator 11 of the present embodiment is a band B ₁ that is a frequency band including the frequency f _{1 of the} transmission signal and a band B ₂ that is a frequency band including the frequency f _{2 of the} control signal. Both are set. Accordingly, the frequency of the transmission signal and the frequency of the control signal are set to be different, and the transmission signal and the control signal are multiplexed on the signal cable 4 for transmitting the output of the modulation device 9 to the wireless device 3. Can be transmitted.

[About the second embodiment]
FIG. 5 is a block diagram showing a configuration of a communication system according to the second embodiment.
The difference between the present embodiment and the first embodiment is that the wireless device 3 includes a control signal generation unit 51 and the signal processing device 2 includes a control signal extraction unit 36. About another structure, it is the same as that of 1st Embodiment.

Control signal generating unit 51 generates a control signal of frequency f _2. The control signal generated by the control signal generation unit 51 includes information regarding the state of the wireless device 3 as information necessary for controlling the wireless transmission unit 46.
The control signal generation unit 51 acquires information indicating the state of the wireless transmission unit 46 such as the temperature of the wireless transmission unit 46 from the wireless transmission unit 46.
In addition, a sensor 52 that measures a value indicating an environment in the housing 45 such as a temperature in the housing 45 is provided in the housing 45 of the wireless device 3. The sensor 52 outputs a value indicating the environment in the housing 45 to the control signal generation unit 51.

The control signal generation unit 51 acquires a value indicating the environment in the housing 45 given from the sensor 52 as information indicating the environmental state in the housing 45.
Control signal generator 51 modulates a carrier of a frequency f _2, and generates a control signal including information obtained from the wireless transmission unit 46 and the sensor 52. The control signal generated by the control signal generation unit 51 is an analog signal, and includes information indicating the state of the wireless transmission unit 46 and information indicating the environmental state in the housing 45.

The control signal generation unit 51 gives the generated control signal to the third band pass filter 53 connected to the subsequent stage of the control signal generation unit 51.
The third band pass filter 53 is set so that the signal pass band includes the frequency f _{2 of the} control signal and prevents the transmission signal from passing. Therefore, when a control signal is given from the control signal generation unit 51, the third band pass filter 53 passes the control signal and removes other signals.

The control signal that has passed through the third band pass filter 53 is supplied to a distribution synthesizer 54 provided between the signal cable 4 and the second band elimination filter 40.
To the distribution synthesizer 54, the signal cable 4, the second band elimination filter 40, and the third band pass filter 53 are connected. The distribution synthesizer 54 connects the signal cable 4, the second band elimination filter 40, and the third band pass filter 53 to each other.
Therefore, the control signal given to the distribution synthesizer 54 is given to the signal cable 4.
The signal cable 4 is also given a ΔΣ modulation signal output from the modulation device 9. Therefore, the control signal and the ΔΣ modulation signal are added to each other in the signal cable 4. A signal obtained by adding the reception signal and the ΔΣ modulation signal is transmitted to the signal cable 4.

Here, the ΔΣ modulation signal output from the ΔΣ modulator 11 (modulation device 9) includes quantization noise over a wide band as shown in FIG.
For this reason, the control signal given to the signal cable 4 may be superimposed on the quantization noise included in the ΔΣ modulation signal.

However, as in the first embodiment, in this embodiment as well, the ΔΣ modulation signal output from the ΔΣ modulator 11 (modulation device 9) suppresses the quantization noise in the band B ₂ including the frequency f _{2 of the} control signal. (See FIG. 3).
For this reason, if a control signal having the frequency f ₂ is applied to the signal cable 4, it is possible to suppress the control signal from being superimposed on the quantization noise of the ΔΣ modulation signal. Thereby, the control signal can be transmitted to the signal cable 4 for transmitting the ΔΣ modulation signal by the modulation device 9 to the wireless device 3.
As a result, it is possible to multiplex and transmit the ΔΣ modulation signal that is a digital signal and the control signal that is an analog signal using the signal cable 4 that is one transmission line.

In the signal processing device 2 of the present embodiment, a distribution synthesizer 35 is connected between the first band elimination filter 12 and the signal cable 4.
In addition to the first band elimination filter 12 and the signal cable 4, a control signal extraction unit 36 is connected to the distribution synthesizer 35. The distribution synthesizer 35 connects them to each other.
Therefore, a signal (a signal obtained by adding the ΔΣ modulation signal and the control signal) transmitted to the signal cable 4 is given to the control signal extraction unit 36.

The control signal extraction unit 36 has a function of extracting a control signal from a signal transmitted to the signal cable 4. The control signal extraction unit 36 includes a band pass filter 36a and a signal processing unit 36b.
The band pass filter 36a has a pass band that allows the control signal to pass therethrough. Thereby, the band pass filter 36a can remove the quantization noise existing outside the band of the control signal in the ΔΣ modulation signal. Therefore, the band pass filter 36a outputs a control signal when a signal transmitted to the signal cable 4 is given.
The control signal output from the bandpass filter 36a is supplied to the signal processing unit 36b, and is output after being subjected to signal processing such as demodulation and amplification by the signal processing unit 36b.

As described above, the control signal extraction unit 36 extracts the control signal from the signal (a signal obtained by adding the ΔΣ modulation signal and the control signal) transmitted to the signal cable 4 and outputs the extracted control signal.
The control signal is a signal for controlling the wireless transmission unit 46. As information necessary for controlling the wireless transmission unit 46, information indicating the state of the wireless transmission unit 46 and the environmental state in the housing 45 are displayed. Information to be displayed.
The signal processing device 2 controls the wireless device 3 (wireless transmission unit 46) based on the information included in the control signal.

In the communication system 1 (antenna system) of this embodiment, as in the first embodiment,
Since the signal relating to the control of the wireless transmission unit 46 can be transmitted to the signal cable 4 for transmitting the output of the modulation device 9 to the wireless device 3, the signal processing device 2 can be provided without providing a new signal path. Control regarding the wireless transmission unit 46 can be performed from the side.

  In the present embodiment, the control signal generated by the control signal generation unit 51 is a signal including information on the state of the wireless device 3 as information necessary for controlling the wireless device 3 (wireless transmission unit 46). However, control information including information necessary for controlling the signal processing device 2 may be used. In this case, control regarding the no-signal processing device 2 can be performed from the wireless device 3 side without providing a new signal path.

[About the third embodiment]
FIG. 6 is a block diagram showing a part of the configuration of the communication system according to the third embodiment.
The difference between the present embodiment and the first embodiment is that the wireless device 3 includes a plurality of wireless transmission units 46 and that the ΔΣ modulation signal output from the modulation device 9 is distributed to the plurality of wireless transmission units 46. It is the point provided with the distributor 60 to perform.

As shown in FIG. 6, the distributor 60 is connected to the subsequent stage of the binarizer 41.
A plurality of second band pass filters 42 (four in the illustrated example) are connected to the subsequent stage of the distributor 60. Further, a plurality of wireless transmission units 46 (four in the illustrated example) are connected to the subsequent stage of the plurality of second band pass filters 42.

The output of the adder 13 (FIG. 1) obtained by adding the ΔΣ modulation signal output from the modulation device 9 (FIG. 1) and the control signal output from the control signal generator 30 (FIG. 1) is the signal cable 4 To the second band elimination filter 40 and the control signal extraction unit 43.
The output of the adder 13 given to the second band elimination filter 40 is binarized by the binarizer 41 after passing through the second band elimination filter 40 as in the first embodiment. 60.

The distributor 60 can distribute the output of the binarizer 41 to each of the plurality of wireless transmission units 46, or can supply the output to a specific wireless transmission unit 46 among the plurality of wireless transmission units 46.
The output of the binarizer 41 given to the distributor 60 is a ΔΣ modulation signal (digital signal). Therefore, the distributor 60 can copy the output of the binarizer 41 by digital processing and distribute it to each wireless transmission unit 46. For this reason, the output of the binarizer 41 can be appropriately distributed without being attenuated.

  As described above, the distributor 60 has a function as a relay device (switching hub) that distributes the output of the binarizer 41 to each wireless transmission unit 46.

  The distributor 60 distributes the output of the binarizer 41 to each second band pass filter 42 in the subsequent stage. The distributed output of the binarizer 41 passes through each second band-pass filter 42 to become a transmission signal and is given to each wireless transmission unit 46.

Each wireless transmission unit 46 adjusts the phase and amplitude of the transmission signal, amplifies the signal, and supplies the amplified signal to an antenna 48 connected to the subsequent stage of each wireless transmission unit 46.
Transmission signals given to the plurality of antennas 48 are radiated and transmitted as radio signals to space.
Thus, in the present embodiment, an array antenna that transmits a transmission signal is configured by the plurality of antennas 48.

As in the first embodiment, the control signal extraction unit 43 includes a band pass filter 43a and a signal processing unit 43b, and extracts a control signal from the output of the adder 13.
The control signal extraction unit 43 gives the extracted control signal to each wireless transmission unit 46 and the distributor 60.

The control signal in the present embodiment includes a signal for controlling the distributor 60 and a signal for controlling each wireless transmission unit 46.
The signal for controlling the distributor 60 includes information on how to distribute the output of the binarizer 41, such as information for specifying the wireless transmission unit 46 that provides the output of the binarizer 41. Yes.

The signal processing unit 43 b of the control signal extraction unit 43 provides the extracted control signal to the distributor 60, the distributor 60, and each wireless transmission unit 46.
The distributor 60 to which the control signal is given distributes the output of the binarizer 41 based on information included in a signal for controlling the distributor 60 among the control signals.
In addition, each wireless transmission unit 46 to which the control signal is given performs wireless transmission based on information related to wireless transmission settings included in a signal for controlling each wireless transmission unit 46 among the control signals.

  In the present embodiment, transmission signals given to a plurality of antennas 48 are individually transmitted by a control signal including information on how to distribute the output of the binarizer 41 and information on wireless transmission settings of each wireless transmission unit 46. Can be controlled. As a result, it is possible to control transmission signals transmitted from the plurality of antennas 48 constituting the array antenna.

  According to the above configuration, the wireless device 3 includes the distributor 60 that distributes the output of the binarizer 41 that is a ΔΣ modulation signal to the plurality of wireless transmission units 46, and in addition to the wireless transmission setting, the distributor Since the signal relating to the control of 60 is included in the control signal, the signal relating to the control of the distributor 60 can be transmitted to the signal cable 4, and the radio transmission unit 46 can be transmitted from the signal processing device 2 side without newly providing a signal path. The distributor 60 can be controlled while performing the above control.

  6 shows the case where the output of the adder 13 (FIG. 1) is given to the wireless device 3 from one signal processing device 2, but as shown in FIG. 7, a plurality of signal processing devices 2 are provided. You may comprise so that the output of the adder 13 (FIG. 1) may be given from (two in the example of a figure).

  Further, in the wireless device 3 of FIG. 6, the case where the second band elimination filter 40 is provided in the front stage of the distributor 60 is illustrated, but the signal cable 4 and the distributor 60 are connected as shown in FIG. The output of the adder 13 (FIG. 1) may be provided to the distributor 60 through the signal cable 4.

  In the modification shown in FIG. 8, the control signal extraction unit 43 extracts the control signal and gives it to the distributor 60. The distributor 60 distributes the output of the adder 13 based on the information regarding the distribution method of the output of the adder 13 included in the given control signal.

A plurality of radio units 61 are connected to the subsequent stage of the distributor 60.
FIG. 9 is a block diagram illustrating a configuration of the wireless unit 61. The radio unit 61 includes a band elimination filter 70, a binarizer 71, a band pass filter 72, a control signal extraction unit 73, and a radio transmission unit 76. The wireless unit 61 has the same configuration as the wireless device 3 of the first embodiment, the band elimination filter 70 corresponds to the second band elimination filter 40, and the binarizer 71 corresponds to the binarizer 41. The bandpass filter 72 corresponds to the second bandpass filter 42, the control signal extraction unit 73 corresponds to the control signal extraction unit 43, and the wireless transmission unit 76 corresponds to the wireless transmission unit 46.

When the output of the adder 13 is distributed from the distributor 60, each wireless unit 61 outputs a transmission signal based on information related to wireless transmission settings included in the control signal, as in the wireless device 3 of the first embodiment. To do.
The transmission signal output from each radio unit 61 is given to the antenna 48 and transmitted as a radio signal.

  Also in the configuration shown in FIG. 9, the distributor 60 can be controlled while controlling the wireless transmission unit 46 from the signal processing device 2 side without providing a new signal path.

[Others]
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive.
In each of the above-described embodiments, the case where the 2-input ΔΣ modulator 11 is used is exemplified, but a multi-input ΔΣ modulator 11 such as 3-input or 4-input may be used.
For example, if a three-input ΔΣ modulator 11 is used, three bands where quantization noise is suppressed can be provided in the band of the ΔΣ modulation signal. As a result, two more control signals can be transmitted using the signal cable 4 in addition to the ΔΣ modulation signal output from the ΔΣ modulator 11.

  The scope of the present invention is defined by the terms of the claims, rather than the meanings described above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 Communication system 2 Signal processing apparatus (transmission apparatus)
DESCRIPTION OF SYMBOLS 3 Radio | wireless apparatus (receiver) 4 Signal cable 9 Modulator 10 Orthogonal modulation part 11 ΔΣ modulator 12 First band elimination filter 13 Adder 16 First input port 17 Second input port 18 Output port 19 First loop filter 19a First input unit 19b Second input unit 19c Differentiator 19d First path 19e Second path 19f Internal filter 19g Adder 19h Feedforward path 20 Second loop filter 20a First input unit 20b Second input unit 20c Differentiator 20d First 1 path 20e 2nd path 20f Internal filter 20g Adder 20h Feed forward path 21 Adder 22 Quantizer 23, 24 Feedback path 30 Control signal generator 31 First band pass filter 33 Connector 34 Housing 35 Distribution synthesizer 36 Control Signal extraction Unit 36a bandpass filter 36b signal processing unit 40 second band elimination filter 41 binarizer 42 second bandpass filter 43 control signal extraction unit 43a bandpass filter 43b signal processing unit 44 connector 45 casing 46 wireless transmission unit 48 Antenna 50 Output terminal 51 Control signal generation unit 52 Sensor 53 Third band pass filter 54 Distribution synthesizer 60 Distribution unit 61 Radio unit 70 Band elimination filter 71 Binary converter 72 Band pass filter 73 Control signal extraction unit 76 Radio transmission unit

Claims (9)

A transmission system for transmitting a ΔΣ modulated signal that is ΔΣ modulated with respect to a communication signal,
A receiver for receiving the ΔΣ modulation signal;
A transmitter that transmits the ΔΣ modulation signal to the receiver via a signal transmission path;
At least one of the transmission device and the reception device transmits the control signal to the other of the transmission device and the reception device by giving a control signal related to control of the transmission device or the reception device to the signal transmission path,
The ΔΣ modulation signal is a transmission system in which quantization noise is suppressed at the frequency of the control signal. The transmission device includes a ΔΣ modulator that performs ΔΣ modulation on the communication signal,
2. The ΔΣ modulator has a characteristic of blocking quantization noise in a first frequency band including the frequency of the communication signal and blocking quantization noise in a second frequency band including the frequency of the control signal. The transmission system described in.   The transmission apparatus includes: a band elimination filter having a signal elimination band including a frequency of the control signal, to which an output of the ΔΣ modulator is provided, and outputs an output of the band elimination filter as the ΔΣ modulation signal. 2. The transmission system according to 2.   The transmission device includes: a ΔΣ modulator that performs ΔΣ modulation on the communication signal; and a band rejection filter that is provided with an output of the ΔΣ modulator and has a signal rejection band including the frequency of the control signal. The transmission system according to claim 1, wherein an output of a filter is output as the ΔΣ modulation signal. The transmitter is
The transmission system according to any one of claims 1 to 4, further comprising a control signal extraction unit that extracts the control signal transmitted from the reception device from a signal transmitted to the signal transmission path. The receiving device is:
The transmission system according to any one of claims 1 to 4, further comprising a control signal extraction unit that extracts the control signal transmitted from the transmission device from a signal transmitted through the signal transmission path. The receiving device is:
The transmission system according to any one of claims 1 to 6, further comprising: a binarizer that binarizes the ΔΣ modulation signal provided through the signal transmission path. An antenna system comprising the transmission system according to claim 1,
The receiving device is:
One or more antenna elements;
One or a plurality of transmitters that wirelessly transmit the communication signal obtained from the ΔΣ modulation signal to the one or a plurality of antenna elements,
The control signal includes a signal related to control of the one or more transmission units,
The one or more transmission units are antenna systems that wirelessly transmit based on the control information transmitted from the transmission device. The receiving device includes a distribution unit that distributes the ΔΣ modulation signal to the plurality of transmission units,
The antenna system according to claim 8, wherein the control signal includes a signal related to control of the distribution unit.