Abstract: The present invention provides a communication device that may suppress unnecessary break points. A communication device 200 includes a noise measuring unit 205 that measures noise occurring on a communication line 300; a communication controlling unit 202 that adjusts an SNR value of a transmission signal based on the noise measured in the noise measuring unit 205 and carries out a communication; a virtual noise determining unit 206 that determines the amount of virtual noise applied to some noise and stores the determined amount of noise in a memory unit 204; and a virtual noise applying unit 207 that applies the amount of noise stored in the memory unit 204 to the noise, wherein the virtual noise determining unit 206 dynamically divides a frequency band and determines the amount of noise of the divided frequency band as the amount of virtual noise.

Abstract: When a mobile terminal device detects the existence of the feature information of an article whose position is requested to be searched, it notifies an article management server of the detected position information and the time information together with the feature information of the article, and the article management server notifies a terminal device of the position information of the target estimated based on the detected position information, the time information and the feature information of the target and causes the terminal device to output the information. With this operation, when an article and the like are searched, they can be effectively searched even if they are not provided with a wireless tag, and thus a probability of discovery can be enhanced.

Abstract: A bit-power distribution ratio calculation unit measures several times an SNR of periodic noise occurring on a communication line to calculate several times, according to the measurement results of the SNR thus measured, a bit distribution ratio to be assigned to each carrier for data transmission for each measurement result. The calculation unit compares the calculated bit distribution ratios with each other to detect a minimum bit value of each carrier to calculate, according to the detected minimum bit values of the respective carriers, a minimum bit distribution ratio including the minimum bit value of each carrier. The calculation unit delivers the minimum bit distribution ratio to a demapping unit and a mapping unit, which conduct data transmission using the minimum bit distribution ratio. Therefore, a multicarrier transmission device can efficiently conduct multicarrier transmission even at occurrence of non-periodic noise.

Abstract: A communication quality controller can avoid, when periodically changing noise is abruptly occurring, disconnection of a communication line used for data communication and prevent resetting of a link speed for the data communication. During the data transmission at a beforehand set link speed, a CRC error counter monitors for a predetermined period of time whether or not an error occurs in a CRC error detector at a period less than a noise period changing periodically. According to presence or absence of the error taking place during the monitoring by the counter, a periodic noise detector determines presence or absence of a periodic noise period abruptly taking place. If presence of the periodic noise is determined, disconnection of an associated communication line is avoided, and after the occurrence of the periodic noise is terminated, the data communication is conducted at the link speed.

Abstract: The present invention provides a communication device that may suppress unnecessary break points. A communication device 200 includes a noise measuring unit 205 that measures noise occurring on a communication line 300; a communication controlling unit 202 that adjusts an SNR value of a transmission signal based on the noise measured in the noise measuring unit 205 and carries out a communication; a virtual noise determining unit 206 that determines the amount of virtual noise applied to some noise and stores the determined amount of noise in a memory unit 204; and a virtual noise applying unit 207 that applies the amount of noise stored in the memory unit 204 to the noise, wherein the virtual noise determining unit 206 dynamically divides a frequency band and determines the amount of noise of the divided frequency band as the amount of virtual noise.

Abstract: When a mobile terminal device detects the existence of the feature information of an article whose position is requested to be searched, it notifies an article management server of the detected position information and the time information together with the feature information of the article, and the article management server notifies a terminal device of the position information of the target estimated based on the detected position information, the time information and the feature information of the target and causes the terminal device to output the information. With this operation, when an article and the like are searched, they can be effectively searched even if they are not provided with a wireless tag, and thus a probability of discovery can be enhanced.

Abstract: Upon detecting existence of characteristic information of a failure, of which search is requested, a mobile terminal device 102 notifies a failure management server 104 of the detected location information and time information together with the characteristic information of the failure, and the failure management server 104 notifies a terminal device 1022 of the location information of the failure to be estimated on the basis of the detected location information, time information, and the characteristic information of articles and allows the terminal device 1022 to output this location information. Thereby, even in the case that no communication apparatus is provided to a target apparatus, a failure can be detected and a probability of notification can be improved.

Abstract: Congestion degree is measured by providing a function for measuring congestion degree of surroundings for a terminal itself and by sharing the information obtained. At least one of cellular phones 102 measures congestion degree of surroundings by a congestion degree measurement unit 102B, transmits it to a main server 104 as congestion information, the main server 104 aggregates the congestion information from the cellular phones 102, stores it, and provides the congestion information relating to a specific location requested for the requester.

Abstract: A first communication apparatus stores at least one frequency band influencing a reduction in transmission rate of a communication apparatus being present on an adjacent line adjacent to a communication line and including a range which is higher than an operation frequency band used by the communication apparatus in a storing unit. The first communication apparatus suppresses a transmission output of a signal in the frequency band stored in the storing unit to output a signal to the communication line.

Abstract: A communication quality controller can avoid, when periodically changing noise is abruptly occurring, disconnection of a communication line used for data communication and prevent resetting of a link speed for the data communication. During the data transmission at a beforehand set link speed, a CRC error counter monitors for a predetermined period of time whether or not an error occurs in a CRC error detector at a period less than a noise period changing periodically. According to presence or absence of the error taking place during the monitoring by the counter, a periodic noise detector determines presence or absence of a periodic noise period abruptly taking place. If presence of the periodic noise is determined, disconnection of an associated communication line is avoided, and after the occurrence of the periodic noise is terminated, the data communication is conducted at the link speed.

Abstract: A data transmission device for executing data transmission in environments where the noise level changes periodically minimizes delay of fast data. A multiplexing/synchronization control section receives data (in which the ratio between fast data and interleave data is fixed) which are supplied from an upper layer device at a prespecified data rate, and separates the data into fast data and interleave data. The fast data is supplied to a tone ordering section without changing its data rate. Meanwhile, an interleaving section executes interleaving to the interleave data, and a rate converter controls the data rate of the interleave data and supplies the interleave data to the tone ordering section.

Abstract: A system for multi-carrier transmission which can secure the transmission capacity under the noise environment whose noise changes cyclically is provided. A mapping section in an ATU-C (ADSL transceiver unit, central office end) memorizes the bit allocation allocating to each carrier and transmission power allocation using for each carrier at the period that the noise generated at the data transmission to a downstream direction is large and the bit allocation allocating to each carrier and transmission power allocation using for each carrier at the period that the noise generated at the data transmission to an upstream direction is large. And a demapping section in an ATU-R (ADSL transceiver unit, remote terminal end) also memorizes the memorized bit allocation and transmission power allocation.

Abstract: A data transmission device for executing data transmission in environments where the noise level changes periodically minimizes delay of fast data. A multiplexing/synchronization control section receives data (in which the ratio between fast data and interleave data is fixed) which are supplied from an upper layer device at a prespecified data rate, and separates the data into fast data and interleave data. The fast data is supplied to a tone ordering section without changing its data rate. Meanwhile, an interleaving section executes interleaving to the interleave data, and a rate converter controls the data rate of the interleave data and supplies the interleave data to the tone ordering section.

Abstract: A multiplexing/synchronization control section receives data (in which the ratio between fast data and interleave data is fixed) which are supplied from an upper layer device at a prespecified data rate, and separates the data into fast data and interleave data. An interleaving section executes interleaving to the interleave data. The fast data and the interleave data, whose data rates have been controlled by a fast data rate converter and an interleave data rate converter respectively, are supplied to a tone ordering section to be assigned to carriers of a symbol (frame). In the case where the amount of data which can be assigned to each NEXT symbol is larger than or equal to a “specific amount” which corresponds to the fixed data rate of the fast data supplied from the upper layer device, the tone ordering section assigns fast data of the “specific amount” to each symbol regardless of whether the symbol is a FEXT symbol or a NEXT symbol.

Abstract: A multi-carrier transmission system and a method thereofor employing a bit distribution method capable of solving the problem set forth above by regarding a plurality of SNR values evaluated at different timings as one SNR value evaluated at different frequency at the same timing and is capable of solving the problem set forth above by realizing a given transmission speed depending upon a plurality of SNR values evaluated at different timings and thus maximizing performance margin.