摘要:
The Reed-Solomon error-correcting circuit in accordance with a first invention is constructed so as to perform parallel operation by two-step pipelined processing in a syndrome generating circuit and an error-correcting circuit. The error-correcting circuit operates in synchronization with a clock with a period of 1/N the period of the received symbol clock, where N≧1, and N is an integer. Further, an error-locator-polynomial/error-evaluator-polynomial calculating circuit in the error-correcting circuit has a memory in which the syndrome is input and a Galois-field operations circuit that is connected to the memory. By these means, the Reed-Solomon error-correcting circuit in the present invention performs high-speed processing with small-scale hardware. Further, in an Euclid's algorithm that obtains an error-locator-polynomial, by performing Galois-field operations, from the syndrome equation S(z)=sk−1zk−1+sk−2zk−2+ . . . +s0, a second invention performs initial setting as M(z)=1, B(z)=sk−1zk−1+sk−2zk−2+ . . . +s0, and, depending on the coefficients of the syndrome equation S(z), as A(z)=sk−2zk−1+sk−3zk−2+ . . . +s0z, L(z)=z, to reduce the number of Galois-field operations.
摘要:
A syndrome calculation unit 101 forming a first pipeline stage, a Euclidean algorithm arithmetic operation/error value calculation unit 102 and a Chien search unit 103 together forming a second pipeline stage, and an error correction unit 105 forming a third pipeline stage are provided. The unit 102 implements, by iterative use of a single inverse element calculator, a single Galois multiplier, and a single Galois adder, the Euclidean algorithm arithmetic operation of finding an error locator polynomial .sigma.(z) and an error evaluator polynomial .omega.(z) from a syndrome polynomial S(z) and the calculation of finding an error value e.sub.u by dividing an error evaluation value .omega.(.alpha..sup.-ju) by an error locator polynomial differential value .sigma.'(.alpha..sup.-ju).
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:
A signal transmitted to an STA 200a from a communication device AP is also received by an STA 200b. Upon reception, the STA 200b measures an RSSI. The STA 200b then creates a state notice frame which includes the measured RSSI, and transmits it to the AP 100. In accordance with the received state notice frame, the AP 100 determines and updates a PHY rate for transmission to the STA 200b. This allows to increase the determination and update frequency of PHY rates than before, resulting in an improved possibility of coping with rapid changes in channel environments.
摘要翻译:从通信装置AP发送到STA200a的信号也由STA200b接收。 在接收时,STA 200b测量RSSI。 STA 200b然后创建包括测量的RSSI的状态通知帧,并将其发送到AP 100.根据接收到的状态通知帧,AP 100确定并更新PHY速率以传输到STA 200b。 这允许增加PHY速率的确定和更新频率,从而提高应对频道环境快速变化的可能性。
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:
An angular velocity sensor includes a stem and a vibrator that is supported by the stem. The vibrator is inclined to a mounting surface of the stem. The angle of inclination of the vibrator to the mounting surface is adjustable. For this reason, the angular velocity sensor also includes a holding member that holds the vibrator. This holding member is elastically deformable. A single material may be folded to shape the holding member.
摘要:
An angular velocity sensor includes a stem and a vibrator that is supported by the stem. The vibrator is inclined to a mounting surface of the stem. The angle of inclination of the vibrator to the mounting surface is adjustable. For this reason, the angular velocity sensor also includes a holding member that holds the vibrator. This holding member is elastically deformable. A single material may be folded to shape the holding member.
摘要:
An apparatus for testing the thermal shock fracture strength of ceramics. The apparatus includes supporting means for supporting a ceramic test piece shaped as a rectangular parallelepiped at a first side surface thereof, force-detecting means for restraining a predetermined location of a second side surface of the ceramic test piece, the second side surface facing the first side surface, the force-detecting means and the supporting means restraining any deformation of the ceramic test piece when the second side surface of the ceramic test piece is heated, the force-detecting means being adapted to detect a force acting on the force-detecting means from the ceramic test piece, which tends to be deformed, but which deformation is restrained, means for moving the supporting means to press the ceramic test piece against the force-detecting means, and a heat-emissive element, which is an electric heater, for covering and heating the second side surface to cause a thermal shock in the ceramic test piece.
摘要:
To provide an inertia sensor and a method for reducing an operation error of the inertia sensor, the sensor and the method being configured such that complicated means is not required, and such that, even at the initial use stage in which the temperature characteristic of the sensor is not learned, and even in the case where the sensor is used in an ambient temperature different from the ambient temperature during the previous use of the sensor, an operation error due to an output change caused by a temperature change can be reduced in a relatively simple and highly accurate manner. An inertia sensor 10 is configured by including at least a sensor element 1 for sensing inertia, a signal processing circuit 2, and a memory 3, and is configured such that memory data 8 for estimating a characteristic of the inertia sensor 10 is stored in the memory 3. An angular velocity sensor and an acceleration sensor are included in the category of the inertia sensor 10.
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.