JP2018137502A - Communication terminal device - Google Patents

Abstract

An object of the present invention is to provide a communication terminal capable of realizing low power consumption without deteriorating delay time until signal detection in a communication network system, and a communication network system using the communication terminal.
A communication terminal device capable of communicating with another communication terminal device forming a communication network, a signal detection unit for detecting presence or absence or strength of a communication frame signal transmitted from the other communication device terminal, and a communication frame A signal receiving unit; and a control unit that controls whether to activate the receiving unit according to a detection result of the signal detecting unit. The signal detecting unit includes at least a first circuit and a second circuit. And the first circuit and the second circuit are capable of independently controlling an intermittent operation in which an operation state and a stop state are repeated.
[Selection] Figure 2

Description

  The present invention relates to a terminal device that performs communication in a communication network system, and relates to a technique for realizing low power consumption of the communication terminal device.

  Regardless of whether it is wireless or wired, high responsiveness and low power consumption are simultaneously required for communication terminal devices used in communication network systems.

  In a communication network system formed by a plurality of communication terminal devices, it is always necessary to operate the communication terminal device so that it can receive a communication frame signal at any time. It becomes an obstacle.

  Therefore, in general, in order to reduce the power consumption of the communication terminal device that constitutes the communication network system, the reception operation and the stop operation are alternately performed at a period sufficiently longer than the communication frame signal long time in the communication terminal device that performs reception. In many cases, repeated intermittent operation is performed.

  However, this method has a drawback that the longer the intermittent period is, the longer it takes to successfully receive a communication frame, and the responsiveness of the communication network system decreases.

  On the other hand, as a conventional technique, in a communication terminal device, a receiving circuit for receiving a communication frame signal transmitted from another communication terminal device and a receiving circuit operable with lower power consumption than the receiving circuit are activated. Disclosed is a communication terminal device that is provided with a dedicated signal detection circuit for determining whether or not a communication frame signal is detected by the signal detection circuit and activates a reception circuit for the first time and receives a retransmitted communication frame signal. (For example, refer to Patent Document 1).

  In order to achieve further reduction in power consumption in this communication terminal device, in general, an intermittent operation in which a reception operation and a stop operation are alternately repeated at a period sufficiently longer than the time of the communication frame signal length in the signal detection circuit. Let

International Publication No. 2005/013637

  The power consumption when the signal detection circuit in the communication terminal device disclosed in Patent Document 1 is intermittently operated by alternately repeating the reception operation and the stop operation in a cycle longer than the time of the communication frame signal length is the signal detection circuit. Depends on configuration and period of intermittent operation. If the configuration of the signal detection circuit is the same, the power consumption decreases as the intermittent period becomes longer.

  On the other hand, when the period of such intermittent operation becomes longer, the delay time required until signal detection becomes longer, and there is a trade-off relationship between power consumption and delay time.

  For this reason, in order to further reduce the power consumption, it is necessary to sacrifice the delay time until signal detection.

  The present invention has been made in view of the above circumstances, and a communication terminal capable of realizing low power consumption without deteriorating delay time until signal detection in a communication system and communication using the same An object is to provide a network system.

  A communication terminal device according to an aspect of the present disclosure is a communication terminal device capable of communicating with another communication terminal device forming a communication network, and detects the presence or strength of a communication frame signal transmitted from the other communication device terminal. A signal detection unit that receives the communication frame signal, and a control unit that controls whether to activate the reception unit according to a detection result of the signal detection unit, and the signal detection unit includes at least a first And a second circuit, and the first circuit and the second circuit can independently control intermittent operation that repeats an operation state and a stop state. It is.

  With this configuration, it is possible to finely adjust the mode of intermittent operation for each of a plurality of circuits constituting the communication detection unit, and further reduction in power consumption can be achieved without impairing the responsiveness of the communication terminal device. it can.

  According to the disclosure of the present application, low power standby in a communication terminal device constituting a communication network system is realized by controlling the intermittent operation of each of a plurality of circuits to save power in a signal detection circuit. With this power saving method, it is possible to realize a communication terminal apparatus capable of waiting for ultra-low power consumption exceeding the conventional power reduction amount.

The figure which shows schematic structure of a communication network system The figure which shows schematic structure of the circuit regarding the reception function of a communication terminal device The figure which shows the waveform at the time of intermittent operation of the signal detection circuit The figure which shows an example of a signal detection circuit The figure which shows the operation state inside the signal detection circuit in local intermittent operation

  Hereinafter, embodiments of a communication terminal device used in a communication network system according to the disclosure of the present application and a signal detection circuit for configuring the communication terminal device will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing an outline of a communication network system according to the disclosure of the present application. The communication network system is composed of at least two communication terminal devices 1.

  The communication terminal device 1 may be a device capable of both transmission and reception, and may be a device capable of only transmission or reception. Two-way or one-way communication is performed between two different communication terminal devices 1. Communication may be either wireless or wired.

  FIG. 2 shows a schematic configuration diagram of a circuit related to the reception function in the communication terminal device 1. A circuit related to the reception function of the communication terminal device 1 includes a signal detection circuit 2, a reception circuit 3, and a control circuit 4.

  The signal detection circuit 2 detects the presence / absence or strength of a communication frame signal transmitted from another communication terminal device 1 that is a communication partner, and transmits the detection result to a control circuit 4 described later.

  The receiving circuit 3 receives a communication frame signal transmitted from another communication terminal device 1 that is a communication partner. The receiving circuit 3 has at least two states of an operation state and a stop state.

  The operating state is a state in which power is supplied to the receiving circuit 3 and the receiving circuit 3 can perform functions necessary for the communication terminal device 1, and the reception of the communication frame signal is also performed in this state.

  On the other hand, the stop state is a state in which a part or all of the functions of the reception circuit 3 are stopped, and a state in which the amount of power consumed per unit time in the reception circuit 3 is small compared to the operation state. Say. This state may be realized by stopping the power supply to a part or all of the circuits of the receiving circuit 3, or may be realized by enabling a signal for stopping the function while the power supply continues. good.

  The control circuit 4 controls whether to activate the receiving circuit 3, that is, whether to shift from the stopped state to the operating state, according to the detection result of the communication frame signal of the signal detection circuit 2.

  When the signal detection circuit 2 detects the presence or intensity of the communication frame signal and the control circuit receives the detection result and the communication frame signal exists or the intensity of the communication frame signal exceeds a certain threshold value, The control circuit 4 shifts the receiving circuit 3 from the stopped state to the operating state so that the receiving circuit 3 can receive the communication frame signal. Necessary processing is performed in the communication terminal device 1 for the communication frame signal received by the receiving circuit 3.

  Similarly to the receiving circuit 3, the signal detection circuit 2 also has two states: an operating state and a stopped state. The signal detection circuit 2 can perform an intermittent operation that repeats an operation state and a stop state at a constant cycle. The signal detection circuit 2 can detect the presence / absence or strength of a communication frame signal only in an operating state during intermittent operation.

  By intermittently operating the signal detection circuit 2, it is possible to suppress the amount of power consumed by the communication device terminal during standby. On the other hand, the period of the intermittent operation and the length of the operation state in one period depend on the activation time of the signal detection circuit 2.

  Here, the activation time means that the signal detection circuit 2 actually detects the presence / absence or strength of the communication frame signal after the signal detection circuit 2 starts to supply power from a stopped state or after a signal for enabling the function is input. It means the time it takes to be able to. This time is included in a part of the time of the operation state of the intermittent operation.

  If the activation time of the signal detection circuit 2 is short, the operation time in the intermittent operation can be shortened, so that the power consumption can be further suppressed. However, if the startup time of the signal detection circuit 2 is long, it is necessary to lengthen the operation time in the intermittent operation, and as a result, the intermittent operation cycle also becomes long.

  FIG. 3 shows the relationship between the communication frame signal long time and the operation state time of the intermittent operation of the signal detection circuit 2 in the communication network system of the present invention. A waveform shown as a communication signal is a communication frame signal transmitted from another communication terminal device 1. Ts indicates the length of the transmission time of the communication frame signal transmitted per time.

  The waveform shown as the long-period intermittent operation in FIG. 3 is a waveform in the intermittent operation when the ON time (operation state time) of the signal detection circuit 2 is longer than the communication frame long time Ts. Is called a long-period intermittent operation.

  The waveform shown as the short cycle intermittent operation is a waveform in the intermittent operation when the ON time of the signal detection circuit 2 is shorter than the communication frame long time Ts, and this operation is referred to as the short cycle intermittent operation. In this intermittent operation, the signal detection circuit 2 repeats a state in which a signal is detected if a communication frame signal is present when the signal is ON, and a signal cannot be detected during an OFF time (stop time). For this reason, when the signal detection circuit 2 can detect a signal more than once continuously during the ON time, it can be determined that a communication frame signal exists.

  In order to realize this short cycle intermittent operation, it is necessary that the activation time of the signal detection circuit 2 is sufficiently shorter than the ON time of the intermittent operation. Therefore, the startup speed of the signal detection circuit 2 is increased, a part of the signal detection circuit 2 having a low startup speed is excluded from the intermittent operation target, or a part of the circuit having a low startup speed is set to the startup speed. It is necessary to devise such as starting up relatively quickly for some of the fast circuits.

  Combining the long-cycle intermittent operation and the short-cycle intermittent operation can realize significant power saving of the signal detection circuit 2.

The waveform shown as the local intermittent operation indicates that the signal detection circuit 2 is operated in the short cycle intermittent operation during the period in which the signal detection circuit 2 was turned on in the long cycle intermittent operation, and the signal detection circuit 2 in the long cycle intermittent operation. The period during which the signal is turned off is a waveform when the signal detection period is turned off. That is, in the case of a long-cycle intermittent operation, the waveform is a case where a short-cycle intermittent operation is locally performed only during a period in which the signal detection circuit 2 has been kept on.
The local intermittent operation may be performed for the entire signal detection circuit 2 or may be performed by only a part of the circuits constituting the signal detection circuit 2. Note that when only some of the circuits perform local intermittent operation (that is, when short-term intermittent operation is locally performed), other circuits may perform long-period intermittent operation. That is, while some of the circuits are performing local intermittent operation, the other circuits continue to be turned on.

  FIG. 4 shows a specific example when the signal detection circuit 2 is composed of a plurality of circuits. The signal detection circuit shown in FIG. 4 includes an LNA, a detector, an LPF, and an ADC. An LNA (Low Noise Amplifier) is a circuit having a function for improving noise performance characteristics of a received signal. The detection circuit is a circuit that detects the presence or absence of a signal or the signal intensity of various modulation waves. An LPF (Low Pass Filter) is a circuit that attenuates a high frequency signal and removes it as noise. An ADC (Analog Digital Converter) is a circuit that converts an analog signal into a digital signal. This configuration is an example, and the circuit configuration of the signal detection circuit is not limited to this.

  When performing the local intermittent operation, it is desirable to operate all the circuits constituting the signal detection circuit 2 in a short cycle intermittent operation. However, it is conceivable that short-term intermittent operation is not performed in the case of a circuit in which the startup speed of each circuit varies and the startup time is not sufficiently short with respect to the ON time.

  FIG. 5 is a diagram showing changes in the operation state of the signal detection circuit 2 and each circuit constituting the signal detection circuit 2 when only a part of the circuit is subjected to local intermittent operation in the signal detection circuit 2 of FIG. Specifically, this corresponds to the waveform in the period Ta of the waveform indicating the local intermittent operation in FIG.

  In FIG. 5, LNA and ADC perform local intermittent operation, and the detector and LPF perform long-term intermittent operation without performing local intermittent operation.

  In addition, in the case of a circuit where the startup speed is slightly slow to start within the range of the short cycle intermittent cycle ON time, startup is advanced ahead of the timing when another circuit with high startup speed switches to the intermittent operation state. It is possible to make it. For example, in FIG. 5, the ADC is started up ahead of the timing at which the ADC switches to the intermittent operation state of the LNA.

  As described above, the local intermittent operation can be realized by performing the intermittent operation or continuing the operation state in accordance with the starting speed of each circuit constituting the signal detection circuit 2.

  The method for reducing the power consumption of the signal detection circuit according to the present invention is a further improvement of a system equipped with a signal detection device / circuit for realizing low power consumption standby, particularly in a wireless / wired communication device used in a general office or a house. This is useful when reducing power consumption.

DESCRIPTION OF SYMBOLS 1 Communication terminal device 2 Signal detection circuit 3 Reception circuit 4 Control circuit

Claims (6)

A communication terminal device capable of communicating with other communication terminal devices forming a communication network,
A signal detection unit for detecting the presence or intensity of a communication frame signal transmitted by the other communication device terminal; and
A receiving unit for receiving the communication frame signal;
According to the detection result of the signal detection unit, comprising a control unit for controlling whether to activate the reception unit,
The signal detection unit includes a plurality of circuits including at least a first circuit and a second circuit, and the first circuit and the second circuit each independently perform an intermittent operation that repeats an operation state and a stop state. A communication terminal device that is controllable. The communication terminal device according to claim 1,
The first circuit performs an intermittent operation at a first cycle, and the second circuit operates intermittently at a second cycle shorter than the first cycle while the first circuit is in an operating state. The communication terminal device characterized by performing. The communication terminal device according to claim 2,
The communication terminal apparatus characterized in that the time required for starting the second circuit is shorter than the time required for starting the first circuit. The communication terminal device according to claim 2,
The communication terminal apparatus characterized in that the amount of power consumed by the second circuit is larger than the amount of power consumed by the first circuit. The communication terminal device according to claim 1,
Both the first circuit and the second circuit perform an intermittent operation at a first cycle, and the timing at which the first circuit switches to the operating state is relative to the timing at which the second circuit switches to the operating state. Communication terminal device characterized by being fast. The communication terminal device according to claim 5,
The communication terminal apparatus characterized in that the time required for starting the second circuit is shorter than the time required for starting the first circuit.