JP2017028652A - Communication device, base station device, and communication method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a communication device capable of switching an operation frequency band of an operator to a high performance one.SOLUTION: A communication device 1 comprises: a first band pass filter 10 which allows a signal to pass through a predetermined first frequency band including a plurality of carrier frequency bands; a second band pass filter 111 which allows a signal out of signals which have passed through the first band pass filter 10 to pass through a predetermined second frequency band; and a terminator 121 which terminates a signal which has passed through the second band pass filter 111. The communication device 1 switches whether the signal which has passed through the second band pass filter 111 is to be terminated or not.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a communication device, a base station device, and a communication method.

RF systems used in mobile network base station apparatuses are required to have higher functionality and higher quality for the development of next-generation communication technology.
In developing an RF system corresponding to the next generation communication technology, there is a need to dynamically change the band pass characteristic of the band pass filter (band pass filter) according to the operation status of the wireless communication service.

  As one of the methods, for example, a plurality of band pass filters having different band pass characteristics (pass frequency bands) are prepared in advance, and they are operated by switching them through switch elements in accordance with the operation of the RF system. The frequency band can be changed as desired.

  As a technique related to the above, for example, Patent Document 1 discloses a matching circuit that operates efficiently by appropriately switching circuit elements to be connected to a plurality of frequency band signals by a switch element or the like. .

JP 2008-113202 A

  When the operating frequency band is switched in accordance with the operation of the RF system, there is a concern that instantaneous signal interruption may occur at the switching timing of the switch element. There is also a concern that the communication quality may change (deteriorate) before and after the switching of the switch element.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide a communication device and a base station device capable of switching a pass frequency band with high performance without causing instantaneous signal interruption. And providing a communication method.

  One aspect of the present invention includes a first band-pass filter that passes a predetermined first frequency band including a plurality of carrier frequency bands, and a predetermined second frequency band among signals that have passed through the first band-pass filter. And a termination unit that terminates the signal that has passed through the second bandpass filter, and switches whether to terminate the signal that has passed through the second bandpass filter.

  One embodiment of the present invention is a base station device including the above-described communication device.

  According to another aspect of the present invention, a first band pass filter passes a predetermined first frequency band including a plurality of carrier frequency bands, and a second band pass filter passes the first band pass filter. Passing through a predetermined second frequency band, terminating the signal that has passed through the second bandpass filter, and switching whether to terminate the signal that has passed through the second bandpass filter; Is a communication method.

  According to the communication apparatus, base station apparatus, and communication method described above, it is possible to switch the pass frequency band to high performance without causing instantaneous signal interruption.

It is a figure which shows the minimum structure of the communication apparatus which concerns on 1st Embodiment. It is a figure which shows the specific function structure of the communication apparatus which concerns on 1st Embodiment. It is the 1st figure explaining the characteristic of the whole communication apparatus concerning a 1st embodiment. It is a 2nd figure explaining the characteristic of the whole communication apparatus which concerns on 1st Embodiment. It is a figure which shows the specific function structure of the communication apparatus which concerns on the modification of 1st Embodiment. It is a figure which shows the specific function structure of the communication apparatus which concerns on the other modification of 1st Embodiment.

<First Embodiment>
Hereinafter, the communication apparatus according to the first embodiment will be described in detail with reference to FIGS. However, in each of the embodiments described below, technically preferable limitations are made in order to carry out the present invention, but the scope of the invention is not limited to only the following embodiments.

FIG. 1 is a diagram illustrating a minimum configuration of a communication apparatus according to the first embodiment.
As shown in FIG. 1, the communication device 1 includes a first band pass filter 10 that passes a predetermined first frequency band including a plurality of carrier frequency bands.
In addition, the communication device 1 includes a second band pass filter 111 that passes a predetermined second frequency band among signals that have passed through the first band pass filter 10.
In addition, the communication device 1 includes a terminator 121 that terminates the signal that has passed through the second bandpass filter 111.
And the communication apparatus 1 switches whether the signal which passed the 2nd bandpass filter 111 is terminated.
The communication device 1 is mounted on a base station device installed in various places in order to realize a wireless communication service by an operator.

(Functional configuration of communication device)
FIG. 2 is a diagram illustrating a specific functional configuration of the communication apparatus according to the first embodiment.
As shown in FIG. 2, the communication device 1 includes a first input / output port P1, a second input / output port P2, a first bandpass filter 10, a second bandpass filter 111, a terminator 121, a switch An element S1 and a circulator C1 are provided.
The various functional configurations described above are electrically connected as shown in FIG. 2 to form a high frequency circuit (RF circuit).

  As shown in FIG. 2, the first input / output port P1 to the second input / output port P2 are electrically connected by a main signal line Q which is a transmission line. The main signal line Q is a signal line through which transmission signals are mainly transmitted. The transmission signal input to the first input / output port P1 transmits the main signal line Q and is output from the second input / output port P2.

In the following description, a transmission signal is transmitted from the first input / output port P1 to the second input / output port P2 using the first input / output port P1 as an input port and the second input / output port P2 as an output port. Various functional configurations of the communication device 1 will be described.
Actually, the second input / output port P2 also functions as an input port for receiving a reception signal received through the antenna element, and the first input / output port P1 is output to a transmission / reception function unit for outputting the reception signal. It also functions as an output port.

  As shown in FIG. 2, the first band pass filter 10 and the circulator C1 are connected to the first band pass filter 10 and the circulator C1 on the main signal line Q from the first input / output port P1 to the second input / output port P2. They are connected in series in order.

The first input / output port P1 is connected to a transmission / reception function unit (not shown) that performs transmission signal generation / output processing (and reception signal reading processing) for wireless communication. The transmission signal input to the first input / output port P1 is transmitted to the first band pass filter 10 through the main signal line Q.
An antenna element (not shown) is connected to the second input / output port P2. The transmission signal transmitted to the antenna element becomes an electromagnetic wave through the antenna element and is radiated into the atmosphere.
In the present embodiment, the transmission signal output by the transmission / reception function unit described above is, for example, a high-frequency signal (RF signal) composed of two different carrier frequency bands (“carrier A0” and “carrier A1” described later). Suppose that

The first band pass filter 10 passes a signal in a predetermined frequency band among the input transmission signals.
Here, as will be described later, the first band pass filter 10 is designed to pass a predetermined first frequency band including a plurality of carrier frequency bands ("carrier A0", "carrier A1").
The transmission signal that has passed through the first band pass filter 10 is transmitted to the circulator C1.

  The circulator C <b> 1 outputs the transmission signal input through the transmission line connected to the first band pass filter 10 to the transmission line connected to the second band pass filter 111. The circulator C1 outputs a transmission signal input through the transmission line to which the second bandpass filter 111 is connected toward the second input / output port P2. Furthermore, the circulator C1 outputs the reception signal input to the second input / output port P2 to the transmission line to which the first band pass filter 10 is connected.

  As shown in FIG. 2, the second bandpass filter 111, the switch element S1, and the terminator 121 are connected in series from the circulator C1 to the ground in the order of the second bandpass filter 111, the switch element S1, and the terminator 121. The In other words, the second band pass filter 111, the switch element S1, and the terminator 121 are branched from the main signal line Q (via the circulator C1) and shunt connected.

The second band pass filter 111 passes a predetermined second frequency band in the transmission signal that has passed through the first band pass filter 10.
As will be described later, the second bandpass filter 111 has a predetermined frequency including a sideband of a specific carrier frequency (for example, “carrier A0”) used in the operation of the wireless communication service among the plurality of carrier frequencies. It is adjusted to pass the band.
The transmission signal that has passed through the second band pass filter 111 is transmitted toward the switch element S1.

The switch element S1 switches whether to terminate the signal that has passed through the second bandpass filter 111. In other words, the switch element S1 switches between enabling and disabling the second band pass filter 111 on the high frequency circuit. Specifically, the switch element S1 electrically short-circuits or opens the transmission line according to a switch control signal separately input from the above-described transmission / reception function unit.
Here, in the present embodiment, in a unit frame defined in the operation of the wireless communication service, a period for performing wireless communication using both the carrier A0 and the carrier A1, and a period for performing wireless communication using only the carrier A0. And are preset. Based on the information about the unit frame, the transmission / reception function unit described above opens the switch element S1 during a period in which wireless communication is performed using both the carrier A0 and the carrier A1, and wireless communication is performed using only the carrier A0. The switch element S1 is controlled to be short-circuited in accordance with the period for performing the above.
When the switch element S1 is open, all the transmission signals that have passed through the second bandpass filter 111 are reflected (100%) at the open end of the switch element S1 and returned to the circulator C1. As a result, all the frequency components of the transmission signal are eventually output to the second input / output port P2, so the second band pass filter 111 is invalidated on the high frequency circuit of the communication device 1.
On the other hand, when the switch element S1 is short-circuited, the transmission signal that has passed through the second bandpass filter 111 is transmitted to the terminator 121 through the switch element S1.

  The terminator 121 is an element that terminates an input transmission signal. Specifically, the terminator 121 converts the transmission signal that has passed through the second bandpass filter 111 into heat and erases it. This prevents the transmission signal that has passed through the second bandpass filter 111 from being reflected by other transmission lines and circuit elements.

Here, when the switch element S <b> 1 is short-circuited, only the frequency component that has passed through the second bandpass filter 111 out of the transmission signal that has passed through the first bandpass filter 10 is terminated by the terminator 121. Then, only the frequency component belonging to the pass band (second frequency band) of the second band pass filter 111 is removed from the transmission signal transmitted from the first input / output port P1 to the second input / output port P2. The data is not transmitted to the input / output port P2.
In other words, the circulator C1, the second band pass filter 111, and the terminator 121 function as a band elimination filter (BEF) that removes frequency components belonging to the second frequency band.

(Characteristics of communication equipment)
FIG. 3 is a first diagram illustrating characteristics of the entire communication device according to the first embodiment.
The band pass characteristic G1 shown in FIG. 3 indicates the first frequency band that the first band pass filter 10 passes. As shown in FIG. 3, the first frequency band includes all operating frequency bands assigned to the operator who handles the communication device 1. In the present embodiment, the first frequency band of the first bandpass filter 10 includes both the carrier A0 and the carrier A1, which are two carrier frequency bands allocated to the operator.
When the switch element S1 is opened, the second band pass filter 111 is disabled on the high frequency circuit. Therefore, the band pass characteristic G1 is the band pass characteristic of the entire communication device 1 when the switch element S1 is opened.
The operator opens the switch element S1 when performing wireless communication using both the carrier A0 and the carrier A1 in the operation of the wireless communication service. Thereby, both carrier A0 and carrier A1, which are a plurality of carrier frequency bands forming a transmission signal, are transmitted from the first input / output port P1 to the second input / output port P2 as they are.

As shown in FIG. 3, a plurality of carrier frequency bands constituting a transmission signal, carrier A0 and carrier A1, are provided adjacent to each other on the frequency axis. Specifically, the carrier A0 has a frequency band of frequencies f1 to f2, and the carrier A1 has a frequency band of frequencies f2 to f3 (assuming f1 <f2 <f3).
The frequency band adjacent to the high frequency side of the carrier A1 is an operation frequency band assigned to another operator different from the operator who handles the communication device 1.

FIG. 4 is a second diagram for explaining the characteristics of the entire communication apparatus according to the first embodiment.
A bandpass characteristic G2 shown in FIG. 4 is a bandpass characteristic of a band elimination filter including the second bandpass filter 111 and the terminator 121. This band elimination filter removes only the frequency band corresponding to the second frequency band of the second band pass filter 111. That is, only the transmission signal that has passed through the second band pass filter 111 is terminated by the terminator 121.
When the switch element S1 is short-circuited, the second band-pass filter 111 is enabled on the high-frequency circuit, so that the band-pass characteristic G3 of the entire communication device 1 is obtained by adding the band-pass characteristic G1 and the band-pass characteristic G2. The combined characteristics are obtained (see FIG. 4).

Here, the band pass characteristic G3 of the entire communication device 1 when the switch element S1 is short-circuited is a boundary frequency (frequency) between an operation frequency band of an operator who handles the communication device 1 and an operation frequency band of another operator. The predetermined frequency band including f3) is removed. That is, the second frequency band of the second band pass filter 111 is designed to include the boundary frequency (frequency f3). In other words, the second frequency band of the second band pass filter 111 is substantially included in the first frequency band of the first band pass filter 10, and is a frequency band narrower than the first frequency band, in particular, It is defined in the high frequency part of the first frequency band.
As a result, the frequency component belonging to the second frequency band is removed from the sideband of the transmission signal (carrier A0), so that it is possible to suppress unnecessary wave power to the operating frequency band of other operators.
In this case, the operator operates the wireless communication service using only the carrier A0.

(Function and effect)
As mentioned above, according to the communication apparatus 1 which concerns on 1st Embodiment, among the transmission signals which passed the 1st band pass filter 10, the frequency component (frequency which belongs to a 2nd frequency band which passed the 2nd band pass filter 111 further) Only the component) is transmitted to the terminator 121. The switch element S1 is configured to switch between enabling and disabling only the second bandpass filter 111.
In this way, regardless of the switching of the switch element S1, the transmission signal that has passed through at least the first bandpass filter 10 is always output through the output port (second input / output port P2). There is no instantaneous interruption of the transmission signal at the switching timing.
Further, since only the desired frequency component (unnecessary wave) of the transmission signal is consumed as heat in the terminator 121, only the desired frequency component can be reliably removed from the transmission signal. Therefore, when the operating frequency band is switched using the switch element S1 in accordance with the operation of the wireless communication service, it is possible to suppress a change in communication quality before and after the switching.

Further, according to the communication device 1 according to the first embodiment, the second bandpass filter 111 passes only the frequency band including the sideband of the carrier frequency (for example, carrier A0) used in the operation of the wireless communication service. Let
In this way, unnecessary waves belonging to the sideband of the carrier frequency are removed, so that emission of unnecessary waves belonging to the operating frequency band of other operators can be suppressed.

  As described above, according to the communication device 1 according to the first embodiment, the transmission frequency band can be switched to high performance without causing an instantaneous interruption of the transmission signal.

  Although the communication apparatus 1 according to the first embodiment has been described in detail, the specific mode of the communication apparatus 1 is not limited to the above-described one, and various design changes and the like can be made without departing from the scope of the invention. It is possible to add

<Modification of First Embodiment>
FIG. 5 is a diagram illustrating a specific functional configuration of a communication device according to a modification of the first embodiment.
As shown in FIG. 5, in addition to the configuration of the first embodiment, the communication device 1 according to this modification further includes a λ / 4 transmission line L, a second bandpass filter 112, a terminator 122, a switch An element S2 and a circulator C2 are provided.

The circulator C2 is connected on the main signal line Q between the circulator C1 and the second input / output port P2. The circulator C1 and the circulator C2 are connected by a λ / 4 transmission line L.
Here, the λ / 4 transmission line L is a transmission line whose length is ¼ of the wavelength λ of the transmission signal.

  The circulator C2 outputs the transmission signal input through the λ / 4 transmission line L to the transmission line connected to the second bandpass filter 112. The circulator C2 outputs a transmission signal input through the transmission line to which the second bandpass filter 112 is connected toward the second input / output port P2. Furthermore, the circulator C2 outputs the reception signal input from the second input / output port P2 to the transmission line to which the λ / 4 transmission line L is connected.

As shown in FIG. 5, the second bandpass filter 112, the switch element S2, and the terminator 122 are connected in series from the circulator C2 to the ground in the order of the second bandpass filter 112, the switch element S2, and the terminator 122. The In other words, the second band pass filter 112, the switch element S2, and the terminator 122 are branched from the main signal line Q (via the circulator C2) and shunt connected.
Accordingly, the second band pass filter 111, the switch element S1, and the terminator 121, and the second band pass filter 112, the switch element S2, and the terminator 122 are connected in parallel between the main signal line Q and the ground. It becomes a mode.

The second band pass filter 112 passes only the second frequency band similar to the second band pass filter 111. The transmission signal that has passed through the second band pass filter 112 is transmitted toward the switch element S2.
The switch element S2 switches whether to terminate the signal that has passed through the second bandpass filter 111. In other words, the switch element S2 switches between enabling and disabling the second band pass filter 112 on the high frequency circuit. Specifically, the switch element S2 electrically short-circuits or opens the transmission line according to a switch control signal separately input from the above-described transmission / reception function unit.
The transmission / reception function unit can control the switch element S1 and the switch S2 independently of each other.

When the switch element S2 is open, the transmission signal that has passed through the second band pass filter 111 is totally reflected (100%) at the open end of the switch element S1 and returned to the circulator C2.
On the other hand, when the switch element S2 is short-circuited, the transmission signal that has passed through the second bandpass filter 112 is transmitted to the terminator 122 through the switch element S2.
Similarly to the terminator 121, the terminator 122 terminates the input transmission signal.

  As described above, in the present modification, the band elimination filter (the combination of the second band pass filters 111 and 112 and the terminators 121 and 122) is branched from the main signal line Q and connected.

When both the switch element S1 and the switch element S2 are short-circuited, only the frequency component that has passed through the second bandpass filter 111 out of the transmission signal that has passed through the first bandpass filter 10 is terminated by the terminator 121. At the same time, only the frequency component that has passed through the second band pass filter 112 is terminated by the terminator 122.
Then, as compared with the first embodiment, the number of configurations (band elimination filters) for removing the second frequency band on the main signal line Q is larger, and thus unnecessary waves are further removed.
In addition, since the switch element S1 and the switch element S2 can be independently controlled, the degree of unnecessary wave removal can be changed as desired according to the operation mode of the communication service.

FIG. 6 is a diagram illustrating a specific functional configuration of a communication apparatus according to another modification of the first embodiment.
As shown in FIG. 6, the communication device 1 according to the present modification includes λ / 4 transmission lines L1 and L2 in addition to the configuration of the first embodiment.

As shown in FIG. 6, the λ / 4 transmission lines L1, L2, the second bandpass filter 111, and the terminator 121 are connected from the circulator C1 to the ground, with the λ / 4 transmission line L1, the λ / 4 transmission line L2, the second The band pass filter 111 and the terminator 121 are connected in series in this order.
The switch element S1 is connected between the intermediate point of the λ / 4 transmission line L1 and the λ / 4 transmission line L2 and the ground.

Similarly to the first embodiment, the switch element S1 electrically short-circuits or opens the transmission line according to a switch control signal separately input from the above-described transmission / reception function unit.
When the switch element S1 is short-circuited, the transmission signal that has passed through the second band-pass filter 111 is short-circuited to the ground through the λ / 4 transmission line L1, all reflected (100%) at the ground, and returned to the circulator C1. It is. Then, since all the frequency components of the transmission signal are output toward the second input / output port P2, the second band pass filter 111 is invalidated on the high frequency circuit of the communication device 1.
On the other hand, when the switch element S1 is opened, the transmission signal output from the circulator C1 is transmitted to the second bandpass filter 111 via the λ / 4 transmission line L1 and the λ / 4 transmission line L2.

  Thus, even if the connection relationship among the switch element S1, the second bandpass filter 111, and the terminator 121 is changed, the same effect as in the first embodiment can be obtained.

Note that each of the communication devices 1 according to the first embodiment and various modifications described above includes the main signal line Q and various functional configurations (second bandpass filter 111 and the like) that configure a band elimination filter. Although it is set as the aspect which provides circulator C1 (C2) in the meantime, in other embodiment, it is not limited to this aspect.
For example, in another embodiment, the various functional configurations that constitute the band elimination filter may be directly connected to the main signal line Q without the circulator C1.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the invention described in the claims and equivalents thereof, as long as they are included in the scope and gist of the invention.

1 Communication Device 10 First Band Pass Filter 111, 112 Second Band Pass Filter 121, 122 Terminator C1, C2 Circulator L, L1, L2 λ / 4 Transmission Line P1 First Input / Output Port P2 Second Input / Output Port Q Main Signal line S1, S2 Switch element

Claims (6)

A first bandpass filter that passes a predetermined first frequency band including a plurality of carrier frequency bands;
A second bandpass filter that passes a predetermined second frequency band of the signal that has passed through the first bandpass filter;
A terminator for terminating the signal that has passed through the second bandpass filter;
With
A communication device that switches whether to terminate a signal that has passed through the second bandpass filter. The communication device according to claim 1, wherein the second bandpass filter and the terminator are branched from a transmission line connecting a signal input port to an output port and connected in series. The communication apparatus according to claim 2, wherein a set of the second bandpass filter and the terminator is connected in a plurality of branches from the transmission line. The second bandpass filter is
The communication apparatus according to any one of claims 1 to 3, wherein a frequency band including at least one sideband of the plurality of carrier frequencies is passed. A base station apparatus comprising the communication apparatus according to any one of claims 1 to 4. Passing a predetermined first frequency band including a plurality of carrier frequency bands by a first band pass filter;
Passing a predetermined second frequency band out of signals passed through the first bandpass filter by a second bandpass filter;
Terminating the signal that has passed through the second bandpass filter;
Switching whether to terminate the signal that has passed through the second bandpass filter;
A communication method comprising:

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