摘要:
A communication device according to the present invention includes: a receiving unit which receives a block transmitted by a communication device; a photocurrent measuring unit which measures a reception quality of the received block; a PHY rate determining unit which determines, based on the reception quality, a PHY rate that is used by the communication device for transmitting a next block; a block size control unit which determines, based on the measured reception quality, a block size; and a transmission unit which transmits feedback information including the determined PHY rate and the determined block size to the communication device, and the block size control unit determines the block size to be a value smaller than a maximum value of a block size that can be transmitted by the communication device, when a value indicating the reception quality of the block is within a predetermined range including a PHY rate threshold.
摘要:
The communication terminal includes: a receiving unit and a transmission unit which serve as a communication unit for signal exchange; a beacon processing unit as a first detection unit that detects, for each channel, the number of the other communication terminals performing wireless communication by receiving a terminal number notification signal from a control device; a data processing unit as a second detection unit that counts, for each channel, the number of the other communication terminals found by receiving acknowledgement signals transmitted from the other communication terminals; a channel control unit that selects a frequency channel having a least difference between the number detected by the beacon processing unit and the number counted by the data processing unit, and causes the receiving unit and the transmission unit to perform the signal exchange via the selected frequency channel.
摘要:
The communication terminal includes a receiving unit and a transmission unit, which serve as a communication unit for signal exchange; and a beacon processing unit as a first detection unit that detects, for each channel, the number of the other communication terminals performing wireless communication by receiving a terminal number notification signal from a control device. Additionally, a data processing unit is provided as a second detection unit that counts, for each channel, the number of the other communication terminals found by receiving acknowledgement signals transmitted from the other communication terminals; and a channel control unit selects a frequency channel having a least difference between the number detected by the beacon processing unit and the number counted by the data processing unit, and causes the receiving unit and the transmission unit to perform the signal exchange via the selected frequency channel.
摘要:
In a receiver, a channel estimation unit estimates channel characteristics of each channel, and a weight generation unit generates a weight matrix used in equalization processing by an equalizer in accordance with the estimated values of channel characteristics for each channel as estimated by the channel estimation unit. Furthermore, a likelihood calculation unit calculates a likelihood indicating a degree of certainty for each transmission stream using the weight matrix generated by the weight generation unit, and an adaptive control unit determines a transmission rate appropriate for transmission of a signal from a transmitter to the receiver in accordance with the likelihood of each transmission stream calculated by the likelihood calculation unit, notifying the transmitter of the determined transmission rate.
摘要:
Provided is a communication method for improving the communication quality of multicast transmission. A grouping table storage section stores a grouping table in which Ack return order positions indicating priority orders of the reception terminals which each return an Ack, and addresses of the reception terminals are set. An Ack return order position notification frame creation section notifies each reception terminal of a corresponding Ack return order position based on the grouping table. An Ack return permission information determination section refers to the grouping table, determines the number of reception terminal that are to be permitted to return an Ack, and creates Ack return permission information in which information about the reception terminals that are to be permitted to return an Ack is set, based on the determined number of reception terminals. A multicast creation section creates a multicast containing the Ack return permission information and transmission data.
摘要:
In a receiver 20, a channel estimation unit 203 estimates channel characteristics of each channel, and a weight generation unit 204 generates a weight matrix used in equalization processing by an equalizer 206 in accordance with the estimated values of channel characteristics for each channel as estimated by the channel estimation unit 203. Furthermore, a likelihood calculation unit 205 calculates a likelihood indicating a degree of certainty for each transmission stream using the weight matrix generated by the weight generation unit 204, and an adaptive control unit 211 determines a transmission rate appropriate for transmission of a signal from a transmitter to the receiver 20 in accordance with the likelihood of each transmission stream calculated by the likelihood calculation unit 205, notifying the transmitter of the determined transmission rate.
摘要:
Provided is a communication method for improving the communication quality of multicast transmission. A grouping table storage section stores a grouping table in which Ack return order positions indicating priority orders of the reception terminals which each return an Ack, and addresses of the reception terminals are set. An Ack return order position notification frame creation section notifies each reception terminal of a corresponding Ack return order position based on the grouping table. An Ack return permission information determination section refers to the grouping table, determines the number of reception terminal that are to be permitted to return an Ack, and creates Ack return permission information in which information about the reception terminals that are to be permitted to return an Ack is set, based on the determined number of reception terminals. A multicast creation section creates a multicast containing the Ack return permission information and transmission data.
摘要:
The present invention aims to provide a transmission device that, in a communication system using multilevel modulation with 2^n levels (n being an integer greater than or equal to two), limits the run length to a predetermined value or less and guarantees DC balance.The transmission device, which transmits data to which 2^n amplitude modulation has been applied, separates data for transmission into n data sequences; encodes one of the n data sequences to guarantee run length, thereby generating a converted data sequence; generates an intermediate data sequence by either inverting or not inverting a specific data sequence so that, based on candidate data, the next output voltage guarantees DC balance; and applies 2^n amplitude modulation to n-bit symbols each of which has a bit in the intermediate data sequence as a most significant bit and bits in the remaining data sequences, excluding the specific data sequence, as subsequent bits.
摘要:
The present invention aims to provide a transmission device that, in a communication system using multilevel modulation with 2̂n levels (n being an integer greater than or equal to two), limits the run length to a predetermined value or less and guarantees DC balance.The transmission device, which transmits data to which 2̂n amplitude modulation has been applied, separates data for transmission into n data sequences; encodes one of the n data sequences to guarantee run length, thereby generating a converted data sequence; generates an intermediate data sequence by either inverting or not inverting a specific data sequence so that, based on candidate data, the next output voltage guarantees DC balance; and applies 2̂n amplitude modulation to n-bit symbols each of which has a bit in the intermediate data sequence as a most significant bit and bits in the remaining data sequences, excluding the specific data sequence, as subsequent bits.
摘要:
A master device transmits a beacon signal including information related to a proximity wireless communication area in a predetermined cycle by using a transmission power which allows the beacon signal to reach beyond the proximity wireless communication area. When a slave device receives the beacon signal from the master device, the slave device estimates a distance to the master device in accordance with the information of the beacon signal. When a wireless communication terminal is located within the proximity wireless communication area, the slave device is connected to the master device by using a proximity wireless communication.