Method and arrangement in a wireless communication system

摘要

The present invention relates to a method and arrangement in base station for scheduling user equipments. The base station is adapted to schedule communication from user equipments by sending contention based grants comprising information indicating if the contention based grant should be used for initial transmission or for retransmission. If it is detected that data is not correctly received due to a collision, the information in a following contention based grant is set to indicate that said contention based grant is to be used for initial transmission, while if data is not correctly received, but no collision is detected, the information is set to indicate that the contention based grant is to be used for retransmission. Corresponding method and arrangement in a user equipment is described.

主权项

1. A method in a base station for scheduling user equipments, the method comprising:
sending a contention based grant of a retransmission process to a set of user equipments within a cell served by the base station; receiving data from at least one of the set of user equipments using the contention based grant; determining whether the data is correctly received from the at least one user equipment; and responsive to determining that the data is not correctly received, the method further comprising the steps:
sending a non-acknowledgement feedback to the set of user equipments; andresponsive to detecting whether the data was not correctly received due to a collision, sending a following contention based grant belonging to the same retransmission process as the first contention based grant to the set of user equipments, wherein the following contention based grant comprises information, based on the detecting step, indicating whether the following contention based grant should be used for initial transmission by non-colliding user equipments that have not previously transmitted data pursuant to the first contention based grant or for retransmission by the at least one user equipment that has previously transmitted data pursuant to the first contention based grant.