摘要:
The first and second nodes in a wireless network estimate first and second channel response. The first node quantizes the first channel response to produce a first bit sequence, and a feed-forward message, which is transmit as a feed-forward message to the second node. The second node quantizes the second channel response using the feed-forward message to produce and an estimate of the first bit sequence, a second bit sequence and a feed-back message, which is transmitted to the first node. Then, the first and second nodes delete bits in the respective bit sequences using the feed-back and feed-forward message to generate first and second private keys with low bit mismatch rate.
摘要:
The first and second nodes in a wireless network estimate first and second channel response. The first node quantizes the first channel response to produce a first bit sequence, and a feed-forward message, which is transmit as a feed-forward message to the second node. The second node quantizes the second channel response using the feed-forward message to produce and an estimate of the first bit sequence, a second bit sequence and a feed-back message, which is transmitted to the first node. Then, the first and second nodes delete bits in the respective bit sequences using the feed-back and feed-forward message to generate first and second private keys with low bit mismatch rate.
摘要:
Data are communicated in a wireless network, between a transmitter and a receiver. The transmitter estimates a first channel response between the receiver and the transmitter, and generates a first key based on the first channel response. The data are encoded at the transmitter using a rate-adaptive code to produce encoded data, and scrambled using the first key before broadcasting. Subsequently, the receiver can estimate a second channel response to generate a second key to be used to descramble the broadcast data.
摘要:
Data are communicated in a wireless network between a transmitter to a receiver. The transmitter estimates a first channel response between the receiver and the transmitter at the transmitter, and generating a first key based on the first channel response. The data are encoded at the transmitter using a rate-adaptive code to produce encoded data, which is scrambling using the first key before broadcasting. Subsequently, the receiver can estimate a second channel response to generate a second key to be used to descramble the broadcast data.
摘要:
A method equalizes and decodes a received signal including a sequence of symbols. Subsequences of the signal are selected, wherein the subsequences are overlapping and time shifted. For each subsequence, statistics of the channel corresponding to a pattern in the subsequence are selected, wherein the statistics include high-order statistics. A transmitted signal corresponding to the received signal is then estimated based on the statistics.
摘要:
Undetectable errors in packets are minimized by verifying the CRC in each packet, setting a CRC flag to 0 to indicate success, and setting the CRC flag to 1 to indicate failure. If at least one packet in the set of packets fails then generate an error pattern E for each packet by comparing the packet that fails with one packet that passed the CRC verification, and comparing the error pattern to a set of known error patterns. Then, setting a CRC flag to 0 to indicate success and passing the payload of each packet and the CRC flag to the application if the difference is less than a predetermined threshold, and otherwise, setting the CRC flag to 1 to indicate failure.
摘要:
Undetectable errors in packets are minimized by verifying the CRC in each packet, setting a CRC flag to 0 to indicate success, and setting the CRC flag to 1 to indicate failure. If at least one packet in the set of packets fails then generate an error pattern E for each packet by comparing the packet that fails with one packet that passed the CRC verification, and comparing the error pattern to a set of known error patterns. Then, setting a CRC flag to 0 to indicate success and passing the payload of each packet and the CRC flag to the application if the difference is less than a predetermined threshold, and otherwise, setting the CRC flag to 1 to indicate failure.
摘要:
A hybrid communication network for a transportation safety system includes a fixed wired nodes and mobile wireless nodes. Because the wired nodes operate independently packets transmitted by the wired nodes to the wireless nodes need to be synchronized. A downlink travel time for downlink packets traveling from a controller to the wireless nodes is determined. Then, the controller schedules downlink data intervals (DDI) based on the downlink travel time; and transmits downlink packets to the wireless nodes during the DDI, such that a latency requirement of the transportation safety system is satisfied.
摘要:
A method allocates bandwidth to channels in an orthogonal frequency division multiple access and time division multiple access (TDMA) network. The network includes a master device (master) communicating with a set of slave devices (slaves). The master defines a set Ψm of logical indices ν of a set of N physical subcarriers for a set of M data streams to be allocated to a set of Nd logical data subcarriers according to Ψm={ν|ν=iM+m, i=0,1,2, . . . , d−1}, where d=Nd/M. The set of N data subcarriers is mapped to the set of Nd logical subcarriers according to the logical indices, and the data subcarriers are allocated to the logical subcarriers.
摘要:
A blanking scheme for mitigating impulsive noise in wireless networks is based on the signal-to-noise ratio (SNR) of symbols. To fully gain the benefits of the SNR-based blanking scheme, two methods are developed, namely a multi-level thresholding scheme in the time-, spatial- and frequency-domains, and a weighted-input error-correction decoding. The symbols are conditioned as a function of the estimated SNR in time-, frequency-, or spatial-domains or combinations therefore, and the conditioning is applied to an amplitude, phase, or energy level, or combinations thereof.