PHYSICAL DOWNLINK CONTROL CHANNEL WITH MULTI- TRANSMISSION RECEPTION POINTS (TRPS)
Embodiments disclosed herein can enable multi-TRP transmission for PDCCH to achieve diversity gain for the potential benefits to URLLC use cases with challenging reliability/robustness requirements. Specifically, multi-TRP transmission for PDCCH can be performed at different levels as follows: 1. PDCCH with multi-TRP transmission on repetition level; 2. PDCCH with multi-TRP transmission on CCE level; and/or 3. PDCCH with multi-TRP transmission on REGB level.
1 . An apparatus for enabling multi-Transmission Reception Point (TRP) transmission, the apparatus comprising:
processor circuitry configured to:
determine a repetition level parameter to indicate a maximum number of repetitions of a plurality of repetitive physical downlink control channel (PDCCH) blind decoding candidates supported by the PDCCH,
determine a repetition interval parameter to indicate a number of Orthogonal Frequency Division Multiplexing (OFDM) symbols between adjacent repetitions of PDCCH blind decoding candidates from among the plurality of repetitive PDCCH blind decoding candidates, and
determine a repetition domain parameter to indicate whether the plurality of repetitive PDCCH blind decoding candidates are to be repeated in the time domain or the frequency domain, and
construct the plurality of repetitive PDCCH blind decoding candidates in accordance with the repetition level parameter, the repetition interval parameter, and the repetition domain parameter; and
radio front end circuitry configured to transmit the plurality of repetitive PDCCH blind decoding candidates over the PDCCH.
2 . The apparatus of claim 1 , wherein each PDCCH blind decoding candidate from among the plurality of repetitive PDCCH blind decoding candidates is cyclically associated with a corresponding Transmission Configuration Indicator (TCI) state from among a plurality of TCI states, each TCI state from among the plurality of TCI states being associated with a different TRP from among a plurality of TRPs.
3 . The apparatus of claim 2 , wherein the processor circuitry is further configured to:
activate the corresponding TCI state from among the plurality of TCI states, each TCI state from among the plurality of TCI states being associated with a different TRP from among a plurality of TRPs, and
map each PDCCH blind decoding candidate from among the plurality of repetitive PDCCH blind decoding candidates to the corresponding TCI state, and
wherein the radio front end circuitry is configured to transmit the plurality of repetitive PDCCH blind decoding candidates in accordance with the corresponding TCI state.
4 . The apparatus of claim 3 , wherein the processor circuitry is further configured to receive a Medium Access Control control element (MAC CE) to activate the corresponding TCI state.
5 . The apparatus of claim 1 , wherein the repetition level parameter, the repetition interval parameter, or the repetition domain parameter is included within a control channel resource set (CORESET) information element (IE) definition.
6 . The apparatus of claim 1 , wherein each PDCCH blind decoding candidate from among the plurality of repetitive PDCCH blind decoding candidates is associated with a plurality of control channel element (CCEs), and
wherein each CCE from among the plurality of CCEs is associated with a plurality of resource element group blocks (REGBs).
7 . The apparatus of claim 1 , wherein the radio front end circuitry is configured to transmit the plurality of repetitive PDCCH blind decoding candidates in a time domain, a frequency domain, or a time-frequency domain.
8 . A method for enabling multi-Transmission Reception Point (TRP) transmission, the method comprising:
determining, by a TRP from among a plurality of TRPs, a repetition level parameter to indicate a maximum number of repetitions of a plurality of repetitive physical downlink control channel (PDCCH) blind decoding candidates supported by the PDCCH;
determining, by the TRP, a repetition interval parameter to indicate a number of Orthogonal Frequency Division Multiplexing (OFDM) symbols between adjacent repetitions of PDCCH blind decoding candidates from among the plurality of repetitive PDCCH blind decoding candidates;
determining, by the TRP, a repetition domain parameter to indicate whether the plurality of repetitive PDCCH blind decoding candidates are to be repeated in the time domain or the frequency domain;
constructing, by the TRP, the plurality of repetitive PDCCH blind decoding candidates in accordance with the repetition level parameter, the repetition interval parameter, and the repetition domain parameter; and
transmitting, by the TRP, the plurality of repetitive PDCCH blind decoding candidates over the PDCCH.
9 . The method of claim 8 , wherein each PDCCH blind decoding candidate from among the plurality of repetitive PDCCH blind decoding candidates is cyclically associated with a corresponding Transmission Configuration Indicator (TCI) state from among a plurality of TCI states, each TCI state from among the plurality of TC states being associated with a different TRP from among a plurality of TRPs.
10 . The method of claim 9 , wherein the constructing comprises:
activating the corresponding TCI state from among the plurality of TCI states, each TCI state from among the plurality of TCI states being associated with a different TRP from among a plurality of TRPs; and
mapping each PDCCH blind decoding candidate from among the plurality of repetitive PDCCH blind decoding candidates to the corresponding TCI state, and
wherein the transmitting comprises transmitting the plurality of repetitive PDCCH blind decoding candidates in accordance with the corresponding TCI state.
11 . The method of claim 10 , wherein the activating comprises receiving a Medium Access Control control element (MAC CE) to activate the corresponding TCI state.
12 . The method of claim 8 , wherein the repetition level parameter, the repetition interval parameter, or the repetition domain parameter is included within a control channel resource set (CORESET) information element (IE) definition.
13 . The method of claim 8 , wherein each PDCCH blind decoding candidate from among the plurality of repetitive PDCCH blind decoding candidates is associated with a plurality of control channel element (CCEs), and
wherein each CCE from among the plurality of CCEs is associated with a plurality of resource element group blocks (REGBs).
14 . The method of claim 8 , wherein the transmitting comprises transmitting the plurality of repetitive PDCCH blind decoding candidates in a time domain, a frequency domain, or a time-frequency domain.
15 . A wireless communication system for enabling multi-Transmission Reception Point (TRP) transmission, the wireless communication system comprising:
a first TRP from among a plurality of TRPs configured to transmit a first plurality of repetitive physical downlink control channel (PDCCH) blind decoding candidates, the first plurality of repetitive PDCCH blind decoding candidates being constructed in accordance with a repetition level parameter to indicate a maximum number of repetitions of the first PDCCH blind decoding candidate, a repetition interval parameter to indicate a number of Orthogonal Frequency Division Multiplexing (OFDM) symbols between adjacent repetitions of the first PDCCH blind decoding candidate, and a repetition domain parameter to indicate whether the first PDCCH blind decoding candidate is to be repeated in the time domain or the frequency domain; and
a second TRP from among the plurality of TRPs configured to transmit a second plurality of repetitive PDCCH blind decoding candidates,
wherein the second plurality of repetitive PDCCH blind decoding candidates are repetitions of the first plurality of repetitive PDCCH blind decoding candidates that are transmitted by the second TRP in accordance with the repetition level parameter, the repetition interval, and the repetition domain parameter.
16 . The wireless communication system of claim 15 , wherein each PDCCH blind decoding candidate from among the first plurality of repetitive PDCCH blind decoding candidates is cyclically associated with a corresponding Transmission Configuration Indicator (TCI) state from among a plurality of TCI states, each TCI state from among the plurality of TCI states being associated with a different TRP from among a plurality of TRPs.
17 . The wireless communication system of claim 16 , wherein the first TRP is further configured to:
activate the corresponding TCI state from among the plurality of TCI states, each TCI state from among the plurality of TCI states being associated with a different TRP from among a plurality of TRPs;
map each PDCCH blind decoding candidate from among the first plurality of repetitive PDCCH blind decoding candidates to the corresponding TCI state; and
transmit the first plurality of repetitive PDCCH blind decoding candidates in accordance with the corresponding TCI state.
18 . The wireless communication system of claim 17 , wherein the first TRP is further configured to receive a Medium Access Control control element (MAC CE) to activate the corresponding TCI state.
19 . The wireless communication system of claim 15 , wherein the repetition level parameter, the repetition interval parameter, or the repetition domain parameter is included within a control channel resource set (CORESET) information element (IE) definition.
20 . The wireless communication system of claim 15 , wherein the first TRP is configured to transmit the first plurality of repetitive PDCCH blind decoding candidates in a time domain, a frequency domain, or a time-frequency domain.