Nec Corporation

Prakash Chaki

Masato Yasuda

Kazuaki Nakajima

Norifumi Kamiya

Norihito Fujita

A communication method and device which can improve error correction performance and power consumption without increasing hardware complexity is disclosed. A communication apparatus includes: a decoder for polar codes, that decodes a codeword in which a frame is partitioned according to a predetermined partitioning rule and each partition includes at least one check bit computed by a predefined checksum equation; a memory that stores a frozen set including frozen bit indices, a non-frozen set including non-frozen bit indices, and a susceptible to error (STE) set including STE indices susceptible to decoding error for each partition; and a controller configured to: compute a check sum of at least one decoded bit for each partition according to the predefined checksum equation; responsive to failure of checksum, initiate a recurrent decoding attempt on the partition; and perform a bit-inversion operation on at least one STE index in each recurrent decoding attempt.

Communication method and device using recurrent decoding iterations for polar codes

A communication apparatus for forward error correction and detection using polar codes comprising a polar encoder that encodes an input vector to output a codeword using a generator matrix of polar code wherein the input vector is a cyclic redundancy check (CRC) codeword of an information block; a memory that stores a frozen set including frozen bit indices and a non-frozen set including non-frozen bit indices sorted in order of error probabilities; and a controller that is configured to take as input the CRC codeword where CRC bits appended to the end of information block and interleave the CRC codeword using at least one of a first interleaver and second interleaver before feeding the CRC codeword to polar encoder such that the first interleaver places at least one CRC bit earlier than its original position in the CRC codeword and a second interleaver selects at least one bit from the CRC codeword whose corresponding index in a parity check matrix of the CRC code has the highest column weight and puts it in the non-frozen bit index with highest error probability.

Method and apparatus for construction of polar codes

A redundant bit generating device that generates redundant bits for error detection, that are added to a block of information bits, includes: a redundant bit calculation function that generates a predetermined number of redundant bits from the information bits according to a CRC polynomial; and a bit interleaving function that dispersedly arranges the predetermined number of redundant bits within the information bits using a permutation pattern determined based on the CRC polynomial.

Method and apparatus for generating redundant bits for error detection

A communication device includes: an encoder that encodes an input vector to output a codeword using a generator matrix of polar code; a memory that stores a frozen set including frozen bit indices and a non-frozen set including non-frozen bit indices; and a controller that is configured to: a) select at least one check bit index from the frozen set in descending order of row weights of the generator matrix and in descending order of index reliabilities of the input vector; b) select at least one non-frozen bit index from the non-frozen set to compute at least one check bit from at least one bit of information bits at the at least one non-frozen bit index; and c) put the at least one check bit at the at least one check bit index.

Communication method and apparatus using polar codes

A method includes the steps of: disconnecting a first device included in a first P2P group from the first P2P group so that the first device joins to a second P2P group; and in synchronization with the first device switching to the second P2P group, disconnecting a second device included in the second P2P group from the second P2P group so that the second device joins to the first P2P group.

Method and system for inter-group communication in a wireless P2P network

A mechanism which can achieve enhanced network performance in wireless P2P groups is disclosed. A method for group reformation in wireless peer-to-peer (P2P) networks, includes: monitoring traffic of a first device of a first P2P group, the first device communicating with a second device of at least one second P2P group; and altering group formation of the first and second P2P groups so as to put the first device and the second device together in a single P2P group, based on monitored traffic of the first device.

Traffic-aware group reformation in a multi-group P2P network

A device includes an upper layer that performs routing at least one packet and a Peer to Peer (P2P) unit that provides information about formation of a wireless P2P network to the upper layer which is higher than a data link layer.

Device within a wireless peer-to-peer network, wireless communication system and control method

A communication method and a system are provided that make it possible to transfer information between groups. The communication method is a communication method in a wireless communication network including a plurality of nodes that can form a peer-to-peer group, wherein an owner node operating as an access point in one group selects one or a plurality of client nodes within this group as delivery nodes, the delivery node disconnects from the group and connects to another group that is present in vicinity, and information is transferred between the delivery node and an owner node of the another group.

Method and system for communication between groups in wireless communication network

A mechanism by which the number of groups can be reduced in a multi-group P2P network is disclosed. A method for group formation in wireless peer-to-peer (P2P) networks, includes: exchanging group-related information between group owners of neighboring P2P groups; deciding on whether a combined group of the neighboring P2P groups meets a predetermined condition of either of the neighboring P2P groups, based on the group-related information of the neighboring P2P groups; and merging the neighboring P2P groups to form at least one single group when the combined group meets the predetermined condition.

Group formation control in multi-group peer-to-peer network

A communication method, a communication system, a wireless terminal, and a wireless control method are provided that make it possible to share information between terminals without forming a group. In a communication method in a wireless communication network including a plurality of terminals (Nto N), a first terminal (N) and a second terminal(Nor N) that belong to different groups, or do not belong to a group, can embed arbitrary information in a control frame () that is sent and received to search for a terminal or another group in vicinity, and notification information (MSG) of one of the terminals is notified to the other terminal by using the control frame.

Communication method, communication system, wireless terminal, and communication control method in wireless communication network

A connection method in a wireless peer-to-peer group of nodes, wherein one of the nodes acts as a leader and others act as clients of the group, includes the steps of: sending credential information required for creating a virtual persistent group configuration from the leader to each of the clients; creating a virtual persistent group configuration at each of the clients which has received the credential information from the leader; and when leadership of the leader disappears, establishing a first-time connection between a first client and a second client based on persistent mechanism by invitation using the virtual persistent group configuration.

Mechanism for quick connection in wireless peer to peer networks

A method includes: performing a scan to discover at least one Peer to Peer (P2P) group; sharing a result of the scan within a first P2P group; preparing a switching schedule of the first P2P group based on the shared result; wherein the switching schedule enables a switching device to disconnect from a first owner device in the first P2P group and to connect with a second owner device in a second P2P group; sharing an information with the second P2P group by using the switching device; and performing communication among the first P2P group and the second P2P group on the basis of the information.

Growing community of inventors

Tokyo, Japan

Prakash Chaki