Automatic retransmission and error recovery for packet oriented point-to-multipoint communication
View Patent ↗Point to multipoint wireless communication, including automatic retransmission and error recovery for packet oriented point to multipoint communication, which integrates adaptive and dynamic responsiveness for parameters for automatic retransmission using wireless communication. A wireless communication link is divided into a downstream portion and an upstream portion. Parameters are selected for automatic retransmission independently for the downstream portion and the upstream portion of the wireless communication link. A BSC controls the selection of parameters for automatic retransmission for all CPE within a cell. As part of a TDD frame, in which the BSC and the CPE share communication bandwidth using a TDMA technique, the BSC includes its selection of parameters for automatic retransmission to be used by CPE within a control section of the TDD frame. The BSC dynamically and adaptively determines new selected parameters for automatic retransmission, in response to conditions of a wireless communication link with each independent CPE. The BSC dynamically and adaptively allocates acknowledgement time slots within the upstream portion of the TDD frame, for use by each selected CPE. The BSC allocates some portion of the upstream bandwidth as a shared resource and some portion of the upstream bandwidth as unshared when there are messages received but not yet acknowledged. The BSC dynamically and adaptively response to acknowledgement and non-acknowledgement messages from each selected CPE, to integrate the automatic retransmission protocol with the TDD frame and the TDMA technique used within that frame.
1. A method of controlling selection of parameters for automatic retransmission in a point-to-multipoint wireless communication link having an upstream portion and a downstream portion, the method comprising the steps of:
selecting parameters for automatic retransmission independently for the downstream portion and the upstream portion of the wireless communication link; and
including the parameters in a control section of a frame, the control section for sending control information downstream.
2. A method of automatic retransmission of upstream data messages in a point-to-multipoint wireless communication network where one or more customer premises equipments (CPE) exchange messages with a base station controller (BSC) along a shared transmission link, the method comprising, at the CPE:
receiving a downstream control message specifying physical (PHY) and media access control (MAC) parameters for use by the CPE to transmit uplink data, the control message further specifying a payload bandwidth grant for transmission of uplink data;
receiving a further allocation of upstream bandwidth for use by the CPE to transmit to the BSC a message associated with automatic retransmission; and
transmitting from the CPE the uplink data within the payload bandwidth grant, using the PHY and MAC parameters,
wherein the PRY and MAC parameters for the CPE are selected independently of the parameters for any other CPE transmitting uplink data on the shared link, based on previous communication between the BSC and the CPE.
3. A method as claimed in claim 2 , further comprising receiving at the CPE a second upstream grant including an allocation of upstream bandwidth for enabling a group of CPEs, including the CPE, to transmit messages associated with automatic retransmission.
4. A method as claimed in claim 2 , further comprising retransmitting the upstream data in response to the message associated with automatic retransmission received at the CPE indicating that the BSC did not receive the upstream data.
5. A method as claimed in claim 2 , further comprising resuming transmission of subsequent downlink data in response to the message associated with the automatic retransmission transmitted by the CPE indicating that the BSC did receive the upstream data.
6. A method as claimed in claim 2 , wherein the physical parameters for automatic retransmission are selected based on the characteristics of the transmission link between the BCS and the CPE.
7. A method as claimed in claim 2 , wherein the physical parameters include a symbol transmission rate.
8. A method as claimed in claim 2 , wherein the MAC parameters include a number of payload data bytes assigned per message.
9. A method as claimed in claim 2 , wherein the physical parameters include a number of payload data bits assigned per symbol.
10. A method as claimed in claim 2 , wherein the physical parameters include a number of error detection bits assigned per symbol.
11. A method as claimed in claim 2 , wherein the physical parameters include a number of error correction bits assigned per symbol.
12. A method as claimed in claim 2 , wherein the MAC parameters include a frequency of acknowledgement messages.
13. A method as claimed in claim 2 , wherein the MAC parameters include a number of message retransmission attempts.