US 2017/0318620 A1 · Connected Mode Discontinuous Reception for Narrow Band Internet of Things

Abstract

A novel and efficient DRX operation mechanism is proposed to maintain the reliability and energy efficiency for NB-IOT systems. In NB-IOT systems, the length of a NB-PDCCH (with repetition) and the interval between two NB-PDCCHs are extended and can be reconfigured by eNB for each UE. The eNB can also adaptively adjusts the DRX parameters accordingly. NB-IOT UE monitors the NB-PDCCH in DRX ON duration, which is configured in number of NB-PDCCHs. Specifically, if a DRX timer duration is configured by the eNB in units of a PDCCH period, the UE should calculate the timer in terms of number of PDCCH user-specific search spaces (USSs), or in terms of PDCCH subframes by multiplying the number of PDCCH periods with the PDCCH repetition level.

Claims20

Dependent claims

A method comprising:

receiving a control signal by a user equipment (UE) for configuring a number of narrowband physical downlink control channel (NB-PDCCH) periods that carry downlink control information (DCI), wherein each NB-PDCCH period refers to an interval between the start of two consecutive NB-PDCCH occasions;
configuring discontinuous reception (DRX) parameters by the UE for DRX operation in radio resource control (RRC) connected mode;
determining a NB-PDCCH user-specific search space (USS) for each NB-PDCCH period, wherein each NB-PDCCH USS comprises a repetition level of NB-PDCCH subframes for NB-PDCCH transmission;
and
monitoring the DCI for a monitoring time such that the UE monitors a total number of NB-PDCCH USSs during an On Duration of each DRX cycle.

2 more elements

Dependencies are inferred from the claim text.

Connected Mode Discontinuous Reception for Narrow Band Internet of Things

Life of this patent

Connected Mode Discontinuous Reception for Narrow Band Internet of Things

Life of this patent

Abstract

Claims20