A system includes an access point and one or more remotes. The access point is configured for receiving signals, and for transmitting signals comprising contention frames, contention grants, and data frames. The one or more remotes include a first remote configured for receiving signals, and configured for transmitting signals comprising contention requests and data frames. The first remote is configured for transmitting one of the contention requests within a selected period of time after receiving one of the contention frames from the access point. The access point is configured for transmitting one of the contention grants to the first remote after receiving one of the contention requests from the first remote. The first remote is configured for transmitting one of the data frames within a selected period of time after receiving one of the contention grants from the access point.