Abstract: A communication apparatus in a multi-hop relay system in which a packet is transmitted and received using a flooding method in a first flooding slot and a second flooding slot each including a plurality of sub-slots, the communication apparatus performs: switching a frequency channel to be used to transmit and receive a packet between a first sub-slot and a second sub-slot in the first flooding slot; and not switching the frequency channel to be used to transmit and receive a packet within the second flooding slot, but switching the frequency channel to be used to transmit and receive a packet between a plurality of the second flooding slots.

Abstract: There is provided a positioning system comprising one or more anchor nodes and one or more tag nodes. The anchor nodes perform time synchronization among the anchor nodes through first communication different from single-hop communication, and share parameters to be used in positioning processing of the tag nodes, transmit the parameters to the tag nodes through single-hop communication, and execute positioning or rangefinding for the tag nodes based on the parameters in a positioning slot in which the positioning processing is executed. The tag nodes perform time synchronization with the anchor nodes through the single-hop communication, and receive the parameters from at least one of the anchor nodes, and execute wireless positioning processing using the single-hop communication with the at least one of the anchor nodes based on the parameters in the positioning slot.

Abstract: A communication apparatus in a multi-hop relay system in which a packet is transmitted and received using a flooding method in a first flooding slot and a second flooding slot each including a plurality of sub-slots, the communication apparatus performs: switching a frequency channel to be used to transmit and receive a packet between a first sub-slot and a second sub-slot in the first flooding slot; and not switching the frequency channel to be used to transmit and receive a packet within the second flooding slot, but switching the frequency channel to be used to transmit and receive a packet between a plurality of the second flooding slots.

Abstract: There is provided a communication system for performing communication by flooding using concurrent transmission among a plurality of communication nodes including a transmission node, a relay node, and a destination node. The transmission node generates and transmits the packet including predetermined transmission data, a first error detection code for the transmission data, and a second error detection code for the transmission data, timing information corresponding to a transmission timing of the packet, and the first error detection code. The relay node receives the packet, performs error detection based on the second error detection code, and updates the second error detection code and reconstructs and transmits the packet if no error is detected. The destination node receives the packet, and performs error detection based on the first error detection code.

Abstract: There is provided a multi-hop relay system including a transmission node and a relay node, communicating using a flooding method. The transmission node is configured to transmit a synchronization packet used to synchronize a plurality of relay nodes. The relay node is configured to perform first reception in a first period at every first cycle corresponding to the predetermined cycle, and second reception in a second period not less than a length of the predetermined period at every second cycle longer than the first cycle. The relay node performs the second reception if the synchronization packet cannot be received by the first reception, and if the synchronization packet is received by the second reception, stops the second reception and performs the first reception if the predetermined condition is determined to be satisfied, and if not, executes synchronization recovery processing.

Abstract: There is provided a multi-hop relay system including a transmission node and a relay node, communicating using a flooding method. The transmission node is configured to transmit a synchronization packet used to synchronize a plurality of relay nodes. The relay node is configured to perform first reception in a first period at every first cycle corresponding to the predetermined cycle, and second reception in a second period not less than a length of the predetermined period at every second cycle longer than the first cycle. The relay node performs the second reception if the synchronization packet cannot be received by the first reception, and if the synchronization packet is received by the second reception, stops the second reception and performs the first reception if the predetermined condition is determined to be satisfied, and if not, executes synchronization recovery processing.

Abstract: There is provided a communication system for performing communication by flooding using concurrent transmission among a plurality of communication nodes including a transmission node, a relay node, and a destination node. The transmission node generates and transmits the packet including predetermined transmission data, a first error detection code for the transmission data, and a second error detection code for the transmission data, timing information corresponding to a transmission timing of the packet, and the first error detection code. The relay node receives the packet, performs error detection based on the second error detection code, and updates the second error detection code and reconstructs and transmits the packet if no error is detected. The destination node receives the packet, and performs error detection based on the first error detection code.