JP2006203361A - Method for sensing interference wave - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for sensing an interference wave capable of sooth communication by detecting an interference wave state within a prescribed time capable of transmission after detecting an interference wave and determining the propriety of changing a used channel. <P>SOLUTION: This method is an interference wave sensing method for sensing the interference wave before transmission when a small power data communication system capable of transmission within a prescribed time t<SB>0</SB>after sensing the interference wave is being operated. Within the prescribed time t<SB>0</SB>, the system performs a plurality of times of transmission in a time shorter than the prescribed time t<SB>0</SB>, performs interference wave sensing at time points 101-10m and 111 before each time of transmission, and performs interference wave sending on the basis of results 101a-10ma, 111a of the interference wave detection. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention provides an interference wave that detects an interference wave before transmission during operation of a low-power data communication system such as a TDD (Time Division Duplex) system that can be transmitted within a specified time after the detection of the interference wave (carrier detection). It relates to the detection method.

  Conventionally, a low-power data communication system does not have a license and is an easy-to-install and easy-to-use system, but who is using it and how to use it because of no license. Therefore, in order to perform orderly communication, it is necessary to detect whether the channel to be used is in use before or during operation. Both are legal requirements. In particular, there is a problem that, unless the jamming wave detection (carrier detection) before transmission in operation is not devised, the line is disconnected even though the disturbance is small, or the line is not switched although there is a disturbance. According to the law, interference is detected before transmission, but transmission is possible within the specified time.

FIG. 8 is a time chart showing the transmission time of a low power data communication system which is a conventional TTD system. In FIG. 8, reference numerals 101 and 111 denote interference wave detection (carrier detection) points before transmission when the transmitter is in operation (TxON), and t ₀ is a prescribed transmission time.

FIG. 9 is a time chart for explaining the problem of transmission time in a low power data communication system which is a conventional TTD system. In FIG. 9, 102 to 10 m are each time point within a prescribed time t _{0 at} which transmission is possible, and in actuality, interference wave detection (carrier detection) cannot be performed, but it is assumed that interference wave detection can be performed at each time point 102 to 10 m. Think about the case. In this case, it is assumed that the interference wave detection results are A and B. In the case of A, as a result of the interference wave detection (carrier detection) at each time point 102 to 10 m, each of 102 a to 10 ma is (1), and 1 is not less than a specified value, which is problematic. In the case of B, as a result of interference wave detection at each time point 102 to 10 m, each of 102 a to 10 ma is (0), and 0 is equal to or less than a specified value, and there is no problem. However, actually, the interference wave detection at each time point 102 to 10 m is not measured because it is a time point within the prescribed time t _{0 that} can be transmitted. Therefore, in the case of A, if the interference wave detection result 101a at the time point 101 is 0 and there is no problem, even if the interference wave detection results 102a to 10ma at the time points 102 to 10m are (1), there is a problem at the time point 111. If the jamming wave detection result 111a in FIG. This may last forever. On the other hand, in the case of B, if the result 101a of the interference wave detection at the time point 101 is 1 and there is a problem, the result of the interference wave detection 102a to 10ma at each time point 102 to 10m is (0) and there is no problem and there is no interference. Regardless of transmission. Note that the parenthesed wave detection results 102a to 10ma in FIG. 9 are not actually measured.

  As described above, even if a level higher than the level that is recognized as a disturbing wave is received within a specified time after transmission without any interference wave detection (carrier detection) problem, that is, even if it is better to stop the line, transmission will continue. There is a possibility. The reverse is also true.

As a known technique related to the present invention, a wireless communication apparatus that periodically sets a measurement period of interference waves is known (see, for example, Patent Document 1).
Japanese Patent No. 3434784

  The object of the present invention is to solve the conventional problem of not considering the interference wave condition within the specified time that can be transmitted after the detection of the interference wave, and to determine the interference wave condition within the specified time that can be transmitted after the detection of the interference wave. An object of the present invention is to provide a jamming wave detection method that detects whether or not a use channel can be changed and enables smooth communication.

  To achieve the above object, the present invention provides an interference wave detection method for performing interference wave detection before transmission during operation of a low-power data communication system capable of transmitting within a specified time after interference wave detection, Transmission is performed a plurality of times within a specified time and in a time shorter than the specified time, interference wave detection is performed before each transmission, and interference wave detection is performed based on the result of the interference wave detection.

  In addition, the present invention is a TDD system that performs interference wave detection before transmission during operation. In a system in which transmission is possible for a certain period of time after detection of interference wave, the transmission time of one time is reduced to reduce the period of time during which interference wave detection is unnecessary. This is a radio interference detection method that has a function of detecting interference before transmission and stopping transmission if the interference is detected even once.

  In addition, the present invention is a TDD system that performs interference wave detection before transmission during operation. In a system in which transmission is possible for a certain period of time after detection of interference wave, the transmission time of one time is reduced to reduce the period of time during which interference wave detection is unnecessary. This is a radio interference detection method that has the function of detecting interference before transmission and detecting the interference multiple times before stopping transmission.

  In addition, the present invention is a TDD system that performs interference wave detection before transmission during operation. In a system in which transmission is possible for a certain period of time after detection of interference wave, the transmission time of one time is reduced to reduce the period of time during which interference wave detection is unnecessary. This is a method of detecting a jamming wave of a radio having a function of detecting a jamming wave before transmission and stopping transmission when all the jamming wave detection results are jammed within a certain period of time.

  In addition, the present invention is a TDD system that performs interference wave detection before transmission during operation. In a system in which transmission is possible for a certain period of time after detection of interference wave, the transmission time of one time is reduced to reduce the period of time during which interference wave detection is unnecessary. Interference detection is performed before transmission, and the average of the interference detection results within a certain period is obtained, and when the average value exceeds the threshold, it is assumed that there is interference and the transmission is stopped. This is an interference wave detection method.

  In addition, the present invention is a TDD system that performs interference wave detection before transmission during operation. In a system in which transmission is possible for a certain period of time after detection of interference wave, the transmission time of one time is reduced to reduce the period of time during which interference wave detection is unnecessary. Interference is detected before transmission, and if there is no interference detection even once, the result within a certain period of time in the past is cleared and interference detection is restarted and restarted for an irregular period of time. Wave detection method.

  In addition, the present invention is a TDD system that performs interference wave detection before transmission during operation. In a system in which transmission is possible for a certain period of time after detection of interference wave, the transmission time of one time is reduced to reduce the period of time during which interference wave detection is unnecessary. Interference is detected before transmission, and if there are no interferences detected multiple times, the results within a certain period of time in the past are cleared and interference detection is started for a certain period of time. It is a detection method.

  In addition, the present invention is a TDD system that performs interference wave detection before transmission during operation. In a system in which transmission is possible for a certain period of time after detection of interference wave, the transmission time of one time is reduced to reduce the period of time during which interference wave detection is unnecessary. Interference is detected before transmission, and if no interference is detected once or multiple times, the results within a certain period of time in the past are cleared and interference detection is restarted and restarted after carrier detection. This is a radio interference detection method that stops transmission if there is an interference at the next interference wave detection point after a certain period of time has not passed.

  In addition, the present invention searches for an unobstructed free channel after power-on, such as a low-power communication system that is an unlicensed device, or when it is reset or returned to the initial state, and uses a channel including a plurality of necessary ones. The operation status of the entire communication system is judged from the remaining number of free channels. When there are many free channels, interference detection during operation is likely to appear. When there are few free channels, interference detection during operation appears. This is an in-operation adaptive interference detection level type interference wave detection method in which interference detection appears moderately when an empty channel is in the middle.

  The interfering wave detection method of the present invention detects interfering wave conditions within a prescribed time that can be transmitted after detecting the interfering wave, determines whether or not the channel to be used can be changed, and enables smooth communication.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a time chart showing a transmission time of an interference wave detection method according to an embodiment of the present invention. In FIG. 1, reference numerals 101 to 10 m and 111 denote jamming wave detection (carrier detection) points before transmission when the transmitter is in operation (TxON), and t ₀ is a prescribed time for transmission. That is, shorter the TDD scheme the transmission time, but the time 101, 111 ... is essential statutory interference wave detection, and other, in transmittable within the prescribed time t _0, a plurality of times in less than the specified time t ₀ time Transmission is performed, and the interference wave is detected at each time point 10 to 10 m before transmission, which is not stipulated by the law, and interference wave detection is performed based on the result of the interference wave detection. Thus, during operation of a low-power data communication system capable of transmitting within a specified time after detection of an interfering wave, there is an interfering wave detection method for detecting an interfering wave before transmission, wherein the specified signal is transmitted within the specified time. Transmission is performed a plurality of times in a time shorter than the time, interference wave detection is performed before each transmission not in accordance with laws and regulations, and interference wave detection is performed based on the result of the interference wave detection.

FIG. 2 is a time chart showing a first operation of the interference wave detection method according to the embodiment of the present invention. In FIG. 2, 101 to 10 m and 111 and 112 are the interference wave detection (carrier detection) time points before transmission when the transmitter is in operation (TxON), 101 a to 112 a are the results of interference wave detection at the time points 101 to 112, t ₀ is a prescribed time for transmission. That is, detection of jamming waves (carrier detection) before transmission during transmitter operation (TxON) is started at time point 101 that is required by law, and at time points 10 to 10 m that are not in the law before time point 111 that is required by the next law. It is assumed that the jamming wave detection is performed and the jamming wave detection results 102a to 10ma at time points 102 to 10m are A and B. In the case of A, if the jamming wave detection result 102a to 10ma is equal to or greater than the specified value (1) even once, the next transmission at the time point 111 is stopped regardless of the jamming wave detection result 111a at the time point 111. . In the case of B, if the interference wave detection results 102a to 10ma are a plurality of interference wave detections equal to or greater than the specified value (1), the next transmission after the time point 111 is performed regardless of the interference wave detection result 111a at the time point 111. Stop.

  FIG. 3 is a time chart showing a second operation of the interference wave detection method according to the embodiment of the present invention. That is, detection of jamming waves (carrier detection) before transmission during transmitter operation (TxON) is started at time point 101 that is required by law, and at time points 10 to 10 m that are not in the law before time point 111 that is required by the next law. It is assumed that the interference wave detection is performed and the interference wave detection results 102a to 10ma at the time points 102 to 10m are A and B. In the case of A, the result 101a of the jamming wave detection at the time point 101 is 0 (below the specified value or less than the set value), the average value of the jamming wave detection results 102a to 10ma is obtained, and the specified value level or the set value or more is obtained. If so, the transmission is stopped regardless of the result 111a of the interference wave detection at the time point 111 because there are many interferences. In the case of B, since the jamming wave detection result 101a at the time point 101 is 1 (more than the specified value or the setting value) and there is a jamming, the transmission is stopped regardless of the jamming wave detection result 111a at the next time point 111.

  FIG. 4 is a time chart showing a third operation of the interference wave detection method according to the embodiment of the present invention. That is, detection of jamming waves (carrier detection) before transmission during transmitter operation (TxON) is started at time point 101 that is required by law, and at time points 10 to 10 m that are not in the law before time point 111 that is required by the next law. It is assumed that the interference wave detection is performed and the interference wave detection results 102a to 10ma at the time points 102 to 10m are A. In the case of A, the result 101a of the jamming wave detection at the time point 101 is 0 (below the specified value or the set value), and the average value of the jamming wave detection results 102a to 10ma is less than the specified value or the set value. If the jamming wave detection result 111a at the next time point 111 is 0, transmission is continued.

  If the result 111a of the interference wave detection at the next time point 111 is 1, it is the same as the state of the interference wave detection result 101a at the time point 101 in the case of FIG. If the result 111a of the interference wave detection at the next time point 111 is 0, the state is the same as the state of the interference wave detection result 101a at the time point 101 in the case of FIG.

  The average value of the interference wave detection results 102a to 10ma at the time points 102 to 10m indicates a congestion value in which the radio wave usage is moderate, and if other channels are free, it is more stable to move to another channel. it can.

  FIG. 5 is a time chart showing a fourth operation of the interference wave detection method according to the embodiment of the present invention. That is, detection of jamming waves (carrier detection) before transmission during transmitter operation (TxON) is started at time point 101 that is required by law, and at time points 10 to 10 m that are not in the law before time point 111 that is required by the next law. Interference wave detection is performed, and results 102a to 10ma of the interference wave detection at time points 102 to 10 m are obtained. When the interference wave detection result 101a at the time point 101 is 0, if the interference wave detection result 102a to 10ma at the time point 102 to 10m is zero even once, the process restarts from there. The meaning of restart means that, if there is 0 within a specified time that can be transmitted by law, it is performed from the beginning without considering the result of interference wave detection so far. More specifically, the interference wave detection time is within the maximum specified time, and the interference wave detection is performed irregularly.

  For example, as shown in FIG. 5, if the result 10na of the interference wave detection at the time point 10n is 0, the operation is restarted, and the time points 10n to 113 are changed to the time points 111 to 116, so that new transmission can be performed. Further, if the interference wave detection result 115a at the time point 115 is 0, the process is restarted, and the time point 116 changes to the time point 121 so that a new transmission can be performed.

  In this case, for example, transmission starts from time point 101 and transmission is possible up to time point 111. If all the interference wave detection results 102a to 111a at time points 102 to 111 are 1, transmission is stopped. In other words, the transmission is stopped only when the disturbance continues within the legally stipulated time.

  In the case of FIG. 5, when all the channels of the low-power data communication system are congested, it is possible to avoid a communication interruption that stops transmission as much as possible.

  FIG. 6 is a time chart for explaining legal interference wave detection (carrier detection). In other words, legal interference detection (carrier detection) is performed at time points 101, 111, 121, 131... At irregular intervals within the permissible legal limits.

  FIG. 7 is a time chart showing a fifth operation of the interference wave detection method according to the embodiment of the present invention. That is, detection of jamming waves (carrier detection) before transmission during transmitter operation (TxON) is started at time point 101 that is required by law, and at time points 10 to 10 m that are not in the law before time point 111 that is required by the next law. Interference wave detection is performed, and results 102a to 10ma of the interference wave detection at time points 102 to 10 m are obtained. If the result 101a of the jamming wave detection at the time point 101 is 0, if the result of the jamming wave detection 102a to 10ma at the time point 102 to 10m is 0 twice, the process restarts from there. The meaning of restart means that if 0 occurs twice within a specified time that can be transmitted by law, the restart is performed from the beginning without considering the result of interference wave detection so far. More specifically, the interference wave detection time is within the maximum specified time, and the interference wave detection is performed irregularly.

  For example, as shown in FIG. 7, if the results 102a and 10na of the jamming wave detections at the time points 102 and 10n are 0, 0 is restarted twice and the time points 10n to 113 are changed to the time points 111 to 116 and newly started. Can be sent. In addition, if the interference wave detection results 113a and 115a at the time points 113 and 115 are 0, 0 becomes two times and restarts, and the time point 116 changes to the time point 121 and a new transmission is possible.

  In this case, for example, transmission starts from time point 101 and transmission is possible up to time point 10 m, and transmission is stopped when the number of 1s becomes m−1 in the results 102a to 111a of the interference wave detection at time points 102 to 111. The restart condition can be set to a plurality of times (not shown).

  In the case of FIG. 7, when all the channels of the low-power data communication system are somewhat congested, it is possible to avoid a communication interruption that stops transmission as much as possible.

  Note that in the 25/27 GHz low-power data communication system, the 500 MHz bandwidth is opened for unlicensed use, and it is estimated that there are very many free channels for the time being. If the effectiveness of this frequency band is accepted, it is expected to become crowded. Therefore, when there was a lot of free channels and it wasn't crowded, it was used instead of a channel that was immediately available, rather than using that channel forcibly even though there was interference in the operation. Better.

  Further, even when there is a jamming wave detection during operation when there is no free channel, if other channels are equal or below, there is a possibility that the operation cannot be performed even if the other channels are moved.

  Therefore, the line can be comfortably used by changing the interference wave detection level during operation depending on the idle channel status.

  In the above embodiment, control is performed so that radio waves from the opposite side communicating with the own station do not arrive during carrier detection, and it is assumed that interference detection can be performed by carrier detection.

  Further, the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiment examples may be appropriately combined.

It is a time chart which shows the transmission time of the jamming wave detection method which concerns on the embodiment of this invention. It is a time chart which shows the 1st operation | movement of the jamming wave detection method which concerns on the example of embodiment of this invention. It is a time chart which shows the 2nd operation | movement of the jamming wave detection method which concerns on the example of embodiment of this invention. It is a time chart which shows the 3rd operation | movement of the jamming wave detection method which concerns on the example of embodiment of this invention. It is a time chart which shows the 4th operation | movement of the jamming wave detection method which concerns on the example of embodiment of this invention. 6 is a time chart for explaining the operation of FIG. 5. It is a time chart which shows the 5th operation | movement of the jamming wave detection method which concerns on the example of embodiment of this invention. It is a time chart which shows the transmission time of the low power data communication system which is the conventional TTD system. It is a time chart for demonstrating the problem of the transmission time of the low power data communication system which is the conventional TTD system.

Explanation of symbols

101 to 10 m, 111... Time of interference wave detection (carrier detection) before transmission when the transmitter is in operation (TxON), t ₀ .

Claims (1)

During operation of a low-power data communication system capable of transmitting within a specified time after detection of jamming waves, a jamming wave detection method for detecting jamming waves before transmission,
Transmitting a plurality of times within the specified time within a time shorter than the specified time, performing interference wave detection before each transmission, and performing interference wave detection based on the result of the interference wave detection Method.

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