US-20230284162-A1 - COMMUNICATION SYSTEM AND RECEIVER

US20230284162A1US 20230284162 A1US20230284162 A1US 20230284162A1US-20230284162-A1

Abstract

Provided is a radio communication technology that can achieve low latency, high reliability, and low jitter characteristics. A transmitter is configured to duplicate a packet and transmit the duplicated packets. The receiver is configured to receive the duplicated packets. The receiver is configured to transfer, to an upper layer in the receiver, a first packet ( 1401, 1403, 1405, 1408 ) that is a packet received earlier out of the duplicated packets. A transfer timing that is a timing with which the first packet ( 1401, 1403, 1405, 1408 ) is transferred to the upper layer includes at least one of: a reception timing of a second packet ( 1402, 1404, 1406, 1407 ) that is a packet received later than the first packet out of the duplicated packets; and a cyclical timing (Cycle time) corresponding to a transmission cycle of the duplicated packets.

Inventors

SHIMODA TADAHIRO
MOCHIZUKI MITSURU
FUKUI NORIYUKI
UCHINO DAICHI

Assignees

MITSUBISHI ELECTRIC CORP

Dates

Publication Date: 20230907
Application Date: 20230512
Priority Date: 20210330

Claims (3)

1 - 3 . (canceled)
4 . A communication system, comprising: a transmitter configured to duplicate a packet and transmit the duplicated packets; and a receiver configured to receive the duplicated packets, wherein the receiver is configured to transfer the duplicated packets to an upper layer in the receiver, the receiver is configured to set a communication state with the transmitter to a dormant state, and the transmitter is configured to set a communication state with the receiver to a non-dormant state.
5 . A receiver configured to receive packets duplicated by a transmitter, wherein the receiver is configured to transfer the duplicated packets to an upper layer in the receiver, the receiver is configured to set a communication state with the transmitter to a dormant state, and the transmitter is configured to set a communication state with the receiver to a non-dormant state.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of and claims the benefit of priority under 35 U.S.C. § 120 from U.S. application Ser. No. 17/281,510, filed Mar. 30, 2021, which is a National Stage of PCT/JP2019/042644 filed Oct. 30, 2019, which claims the benefit of priority under 35 U.S.C. § 119 from Japanese Application No. 2018-204805 filed Oct. 31, 2018, the entire contents of which are incorporated herein by reference TECHNICAL FIELD The present invention relates to a radio communication technology. BACKGROUND ART The 3rd generation partnership project (3GPP), the standard organization regarding the mobile communication system, is studying communication systems referred to as long term evolution (LTE) regarding radio sections and system architecture evolution (SAE) regarding the overall system configuration including a core network and a radio access network which is hereinafter collectively referred to as a network as well (for example, see Non-Patent Documents 1 to 5). This communication system is also referred to as 3.9 generation (3.9 G) system. As the access scheme of the LTE, orthogonal frequency division multiplexing (OFDM) is used in a downlink direction and single carrier frequency division multiple access (SC-FDMA) is used in an uplink direction. Further, differently from the wideband code division multiple access (W-CDMA), circuit switching is not provided but a packet communication system is only provided in the LTE. The decisions taken in 3GPP regarding the frame configuration in the LTE system described in Non-Patent Document 1 (Chapter 5) are described with reference to FIG. 1. FIG. 1 is a diagram illustrating the configuration of a radio frame used in the LTE communication system. With reference to FIG. 1, one radio frame is 10 ms. The radio frame is divided into ten equally sized subframes. The subframe is divided into two equally sized slots. The first and sixth subframes contain a downlink synchronization signal per radio frame. The synchronization signals are classified into a primary synchronization signal (P-SS) and a secondary synchronization signal (S-SS). Non-Patent Document 1 (Chapter 5) describes the decisions by 3GPP regarding the channel configuration in the LTE system. It is assumed that the same channel configuration is used in a closed subscriber group (CSG) cell as that of a non-CSG cell. A physical broadcast channel (PBCH) is a channel for downlink transmission from a base station device (hereinafter may be simply referred to as a “base station”) to a communication terminal device (hereinafter may be simply referred to as a “communication terminal”) such as a user equipment device (hereinafter may be simply referred to as a “user equipment”). A BCH transport block is mapped to four subframes within a 40 ms interval. There is no explicit signaling indicating 40 ms timing. A physical control format indicator channel (PCFICH) is a channel for downlink transmission from a base station to a communication terminal. The PCFICH notifies the number of orthogonal frequency division multiplexing (OFDM) symbols used for PDCCHs from the base station to the communication terminal. The PCFICH is transmitted per subframe. A physical downlink control channel (PDCCH) is a channel for downlink transmission from a base station to a communication terminal. The PDCCH notifies of the resource allocation information for downlink shared channel (DL-SCH) being one of the transport channels described below, resource allocation information for a paging channel (PCH) being one of the transport channels described below, and hybrid automatic repeat request (HARD) information related to DL-SCH. The PDCCH carries an uplink scheduling grant. The PDCCH carries acknowledgement (Ack)/negative acknowledgement (Nack) that is a response signal to uplink transmission. The PDCCH is referred to as an L1/L2 control signal as well. A physical downlink shared channel (PDSCH) is a channel for downlink transmission from a base station to a communication terminal. A downlink shared channel (DL-SCH) that is a transport channel and a PCH that is a transport channel are mapped to the PDSCH. A physical multicast channel (PMCH) is a channel for downlink transmission from a base station to a communication terminal. A multicast channel (MCH) that is a transport channel is mapped to the PMCH. A physical uplink control channel (PUCCH) is a channel for uplink transmission from a communication terminal to a base station. The PUCCH carries Ack/Nack that is a response signal to downlink transmission. The PUCCH carries channel state information (CSI). The CSI includes a rank indicator (RI), a precoding matrix indicator (PMI), and a channel quality indicator (CQI) report. The RI is rank information of a channel matrix in the MIMO. The PMI is information of a precoding weight matrix to be used in the MIMO. The CQI is quality information indicating the quality of received data or channel quality. In additi