摘要:
A rate conversion apparatus 10 includes a quantization parameter setting unit 107 and a rounding threshold value setting unit 108. The quantization parameter setting unit 107 determines a quantization parameter change amount according to a code amount of encoded data output from a variable length encoding unit 109 and a target code amount. The quantization parameter setting unit 107 adds a first quantization amount used in an image before conversion to the quantization parameter change amount, to generate a second quantization parameter to be used in re-quantization processing in a quantization unit 105. The rounding threshold value setting unit 108 sets the rounding threshold value according to the quantization parameter change amount. The quantization unit 105 performs re-quantization using the second quantization parameter and the rounding threshold value.
摘要:
Retransmission control and retransmission are performed at a lower priority than the transmission of multicast packets from a transmission apparatus to two or more reception apparatuses. A communication apparatus performs wireless multicast transmission to reliable transmit packets. In a transmission side terminal, sequence numbers are attached at a layer higher than the Mac layer to each of secured-bandwidth or priority control-type Mac layer multicast packets, and in a plurality of reception side terminals, missing packets are detected using the sequence numbers, and bandwidth other than the secured bandwidth or lower priority packets are used to perform retransmission requests. The transmission terminal retransmits data using bandwidth other than the secured bandwidth or lower priority packets, thereby enabling favorable reception of audio, video and data when transmitting the audio, video and data in real-time to the reception terminals using wireless secured bandwidth-type or priority control-type Mac layer multicast transmission.
摘要:
In a network area of a wireless network managed by a wireless master device, a wireless slave device performs wireless network communication with another wireless slave device connected by wire to a terminal, and wired network communication with a terminal connected by wire to the wireless slave device. The wireless slave device includes a wireless reception unit (121) that wirelessly receives a notification frame including a MAC address of the terminal connected by wire to the other wireless slave device and a MAC address of the other wireless slave device, a storage unit (112) that associates and stores the MAC address of the other wireless slave device and the MAC address of the terminal both included in the wirelessly received notification frame, a wire reception unit (120) that receives a frame transmitted from the terminal connected by wire to the wireless slave device, and a filtering unit (111) that discards the frame if the transmission destination MAC address of the frame received by wire does not match the MAC address stored in the storage unit.
摘要:
A wireless slave device for performing wireless network communication with another wireless slave device, the other wireless slave device being connected to a terminal, and wired network communication with a terminal, the wireless slave device including a wireless reception unit that wirelessly receives a notification frame including a MAC address of the terminal connected to the other wireless slave device and a MAC address of the other wireless slave device, a storage unit that associates and stores the MAC address of the other wireless slave device and the MAC address of the terminal both included in the wirelessly received notification frame, a wire reception unit that receives a frame transmitted from the terminal connected to the wireless slave device, and a filtering unit that discards the frame if the transmission destination MAC address of the frame received by wire does not match the MAC address stored in the storage unit.
摘要:
A wireless communication system includes a wireless terminal and a plurality of base stations that can communicate with each other via a predetermined communication path that is different from the wireless communication path to the wireless terminal. The wireless terminal transmits a request signal to one of the base stations to request a response signal from another base station. The one base station transfers the received request signal to the other base station via the predetermined communication path. Upon reception of the request signal transferred from the one base station, the second base station transmits a response signal to the wireless terminal via the predetermined channel. The wireless terminal receives the response signal transmitted from the second base station via the predetermined channel.
摘要:
A wireless communication system includes a wireless terminal and a plurality of base stations that can communicate with each other via a predetermined communication path that is different from the wireless communication path to the wireless terminal. The wireless terminal transmits a request signal to one of the base stations to request a response signal from another base station. The one base station transfers the received request signal to the other base station via the predetermined communication path. Upon reception of the request signal transferred from the one base station, the second base station transmits a response signal to the wireless terminal via the predetermined channel. The wireless terminal receives the response signal transmitted from the second base station via the predetermined channel.
摘要:
A relay device according to the present invention includes: a receiving unit which receives a frame; a transmitting unit which transmits a frame; a frame determination unit which stores therein the first frame when the frame determination unit determines that the received frame is the first frame; a proxy ACK generation unit which generates a third frame which is a proxy frame of a second frame which is a frame to be transmitted from the receiving device, as a receipt acknowledgement to the first frame; and a communication control unit which: causes the transmitting unit to transmit the third frame; sets an extended active period in the inactive period subsequent to the active period; and transmits the first frame in the extended active period when the receiving unit does not receive the second frame within a predetermined period after reception of the first frame.
摘要:
An energy controller, as a communication device, transmits and receives data by transmitting a signal for establishing transmission and reception of the data to network-connected home appliances. The energy controller includes a power saving control unit that determines a transmission period such that the transmission period during which the signal is transmitted is increased as a power value difference increases, which is a value obtained by subtracting the total power consumption value of a power consumption appliance from available power supply value to the power consumption appliance including the network-connected home appliances; and a wireless communication IF for transmitting the signal containing the information indicating the transmission period to the network-connected home appliances in order to set the network-connected home appliances in an active state with a period according to the transmission period.
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:
In serial transmission of a mixture of isochronous data and anisochronous data, communications through a transmission path with a high ratio of occurrence of transmission errors may disturb images during streaming reproduction and produce noise in sound. To solve this problem, the isochronous data that has not been successfully received is retransmitted by using an anisochronous region. Thus, a transmission error of the isochronous data can be reduced without impairment of isochronous characteristics of the data.