Communication method and apparatus
A network device sends multicast configuration information to a terminal device, where the multicast configuration information corresponds to a first multicast service, the multicast configuration information includes first indication information, and the first indication information indicates that the terminal device sends first feedback information for the first multicast service. The terminal device receives the first multicast service based on the first multicast configuration information, and then sends the first feedback information corresponding to the first multicast service to the network device based on the first indication information in the first multicast configuration information. The feedback mechanism applies to a multicast transmission technology and improves transmission reliability of a multicast service.
1 . A communication method, comprises:
receiving multimedia broadcast multicast service subframe configuration from a network device, wherein the multimedia broadcast multicast service subframe configuration indicates subframes for receiving a downlink multimedia broadcast multicast service single frequency network (MBSFN) service;
determining a subcarrier spacing configured with a specific value;
determining a minimum time unit corresponding to the subcarrier spacing;
determining whether the minimum time unit satisfies a valid minimum time unit condition; and
receiving the downlink MBSFN service in the valid minimum time unit in response to the minimum time unit satisfying the valid minimum time unit condition, the valid minimum time unit condition being that all subframes corresponding to the minimum time unit are used for the downlink MBSFN service.
2 . The method according to claim 1 , wherein the specific value is 0.37 kHz, and the minimum time unit is a slot of 3 ms.
3 . The method according to claim 1 , wherein the multimedia broadcast multicast service subframe configuration is MBSFN-SubframeConfig.
4 . The method according to claim 1 , wherein the multimedia broadcast multicast service subframe configuration includes a radio frame allocation period, a radio frame allocation offset, and a subframe allocation; wherein
the radio frame allocation period and the radio frame allocation offset indicate a radio frame for receiving the downlink MBSFN service, and the subframe allocation indicates the subframes for receiving the downlink MBSFN service in the radio frame.
5 . A communication method, comprises:
sending multimedia broadcast multicast service subframe configuration to a terminal device, wherein the multimedia broadcast multicast service subframe configuration indicates subframes for sending a downlink multimedia broadcast multicast service single frequency network (MBSFN) service;
determining a subcarrier spacing configured with a specific value;
determining a minimum time unit corresponding to the subcarrier spacing;
determining whether the minimum time unit satisfies a valid minimum time unit condition; and
sending the downlink MBSFN service in the valid minimum time unit in response to the minimum time unit satisfying the valid minimum time unit condition, the valid minimum time unit condition being that all subframes corresponding to the minimum time unit are used for the downlink MBSFN service.
6 . The method according to claim 5 , wherein the specific value is 0.37 kHz, and the minimum time unit is a slot of 3 ms.
7 . The method according to claim 5 , wherein the multimedia broadcast multicast service subframe configuration is MBSFN-SubframeConfig.
8 . The method according to claim 5 , wherein the multimedia broadcast multicast service subframe configuration includes a radio frame allocation period, a radio frame allocation offset, and a subframe allocation; wherein
the radio frame allocation period and the radio frame allocation offset indicate a radio frame for sending the downlink MBSFN service, and the subframe allocation indicates the subframes for sending the downlink MBSFN service in the radio frame.
9 . An apparatus, comprising:
one or more processors; and
one or more memories coupled to the one or more processors and storing programming instructions for execution by the one or more processors to cause the apparatus to perform a method comprising:
receiving multimedia broadcast multicast service subframe configuration from a network device, wherein the multimedia broadcast multicast service subframe configuration indicates subframes for receiving a downlink multimedia broadcast multicast service single frequency network (MBSFN) service;
determining a subcarrier spacing configured with a specific value;
determining a minimum time unit corresponding to the subcarrier spacing;
determining whether the minimum time unit satisfies a valid minimum time unit condition; and
receiving the downlink MBSFN service in the valid minimum time unit in response to the minimum time unit satisfying the valid minimum time unit condition, the valid minimum time unit condition being that all subframes corresponding to the minimum time unit are used for the downlink MBSFN service.
10 . The apparatus according to claim 9 , wherein the specific value is 0.37 kHz, and the minimum time unit is a slot of 3 ms.
11 . The apparatus according to claim 9 , wherein the multimedia broadcast multicast service subframe configuration is MBSFN-SubframeConfig.
12 . The apparatus according to claim 9 , wherein the multimedia broadcast multicast service subframe configuration includes a radio frame allocation period, a radio frame allocation offset, and a subframe allocation; wherein
the radio frame allocation period and the radio frame allocation offset indicate a radio frame for receiving the downlink MBSFN service, and the subframe allocation indicates the subframes for receiving the downlink MBSFN service in the radio frame.
13 . An apparatus, comprising:
one or more processors; and
one or more memories coupled to the one or more processors and storing programming instructions for execution by the one or more processors to cause the apparatus to perform a method comprising:
sending multimedia broadcast multicast service subframe configuration to a terminal device, wherein the multimedia broadcast multicast service subframe configuration indicates subframes for sending a downlink multimedia broadcast multicast service single frequency network (MBSFN) service;
determining a subcarrier spacing configured with a specific value;
determining a minimum time unit corresponding to the subcarrier spacing;
determining whether the minimum time unit satisfies a valid minimum time unit condition; and
sending the downlink MBSFN service in the valid minimum time unit in response to the minimum time unit satisfying the valid minimum time unit condition, the valid minimum time unit condition being that all subframes corresponding to the minimum time unit are used for the downlink MBSFN service.
14 . The apparatus according to claim 13 , wherein the specific value is 0.37 kHz, and the minimum time unit is a slot of 3 ms.
15 . The apparatus according to claim 13 , wherein the multimedia broadcast multicast service subframe configuration is MBSFN-SubframeConfig.
16 . The apparatus according to claim 13 , wherein the multimedia broadcast multicast service subframe configuration includes a radio frame allocation period, a radio frame allocation offset, and a subframe allocation; wherein
the radio frame allocation period and the radio frame allocation offset indicate a radio frame for sending the downlink MBSFN service, and the subframe allocation indicates the subframes for sending the downlink MBSFN service in the radio frame.
17 . The method according to claim 1 , wherein the all subframes corresponding to the minimum time unit used for the downlink MBSFN service has a quantity of subframes equal to 3.
18 . The method according to claim 1 , wherein the minimum time unit is numbered in increasing order from 0 to 12 in a 40 millisecond (ms) period starting at nf mod 4=0, where nf is a radio frame number.
19 . The method according to claim 18 , wherein the minimum time unit with a number 0 starts at 1 ms in the 40 ms period.
20 . The method according to claim 5 , wherein the minimum time unit is numbered in increasing order from 0 to 12 in a 40 millisecond (ms) period starting at nf mod 4=0, where nf is a radio frame number.
21 . The method according to claim 20 , wherein the minimum time unit with a number 0 starts at 1 ms in the 40 ms period.
22 . The apparatus according to claim 9 , wherein the minimum time unit is numbered in increasing order from 0 to 12 in a 40 millisecond (ms) period starting at nf mod 4=0, where nf is a radio frame number.
23 . The apparatus according to claim 22 , wherein the minimum time unit with a number 0 starts at 1 ms in the 40 ms period.
24 . The apparatus according to claim 13 , wherein the minimum time unit is numbered in increasing order from 0 to 12 in a 40 millisecond (ms) period starting at nf mod 4-0, where nf is a radio frame number.
25 . The apparatus according to claim 24 , wherein the minimum time unit with a number 0 starts at 1 ms in the 40 ms period.