MULTIPLE PACKET SOURCE ACKNOWLEDGEMENT

• US 20080259891A1
• Filed: 04/17/2007
• Published: 10/23/2008
• Est. Priority Date: 04/17/2007
• Status: Abandoned Application

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Dent, Paul W.
• Application Number:
  US11/736,030
• Publication Number:
  US 20080259891A1
• Time in Patent Office: Days
• US Class Current: 370/342
• CPC Class Codes: H04L 1/0057 Block codes H04L1/0061, H04L1/0064 take precedence
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/0073 Special arrangements for feedback channel
• CPC Class Codes: H04L 1/1614 using bitmaps
• CPC Class Codes: H04L 2001/0093 Point-to-multipoint
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals

Abstract

A multi-bit acknowledgement word (44) is prepared by a first communications station 22 (such as a base station) for separately acknowledging the success or failure of data packets received over plural communication channels (42) from respective plural second communication stations 28 (such as terminals). The acknowledgement word (44) is a “joint” or “common” acknowledgement word in the sense that one and the same acknowledgement word provides acknowledgement information for data packets received from plural second communication stations. Either separately or in conjunction with the joint acknowledgement word, a terminal checking code (62) can be employed for determining whether a packet is received on a both in a correct channel and from a correct terminal. The terminal checking code (62) comprise a cyclic redundancy check code formed over data bits (66) of the data packet and a terminal identifier (68) of the terminal (28).

Claims

1. A method of acknowledging data packets received by a first communication station from plural second communication stations, the method comprising:

the first communication station informing the second communication stations of respective channel assignments for the second communication stations;

the second communication stations using their respectively assigned channels for transmitting data packets to the first communication station;

performing a packet error check at the first communication station for each data packet;

in accordance with a result of each packet error check, setting an associated bit of a multi-bit acknowledgement word whereby the acknowledgement word has respective bits set for plural ones of the second communication stations;

transmitting the acknowledgement word from the first communication station to the plural second communication stations.

2. The method of claim 1, wherein the bit set in accordance with the result of the packet error check is associated with a particular channel and packet position on the channel.

3. The method of claim 1, wherein the first communication station is a cellular base station of a cellular network and the second communication stations are wireless terminals.

4. The method of claim 1, wherein the respective channel assignments comprise an assignment of at least one of:

a radio channel frequency;

a group of one or more timeslots in a time division multiplex frame;

a duration of the channel assignment;

a number of packets that may be transmitted using the channel assignment;

one or more Code Division Multiple Access codes;

a modulation and coding scheme to use for transmitting a packet;

an assignment of packet size.

5. The method of claim 1, wherein the act of performing the packet error check for a received packet at the first communication station comprises using an identifier of the second communication station that was assigned the channel on which the packet was received.

6. The method of claim 5, wherein the act of using the identifier of the second communication station that was assigned the channel on which the packet was received comprises:

appending the identifier of the second communication station to data bits of the received packet;

determining a cyclic redundancy check code over the identifier and the data bits of the received packet.

7. The method of claim 1, wherein the act of transmitting the acknowledgement word from the first communication station to the plural second communication stations comprises transmitting a first portion of the acknowledgement word but only transmitting a second portion of the acknowledgement word if configuration of the channel assignments requires transmission of the second portion of the acknowledgement word.

8. The method of claim 7, further comprising choosing an association of the bits of the acknowledgement word to packet positions in the channels such that the total required acknowledgement word length is minimized for the most probably configuration of channel assignments.

9. The method of claim 1, further comprising using a compression algorithm to reduce a number of bits of the acknowledgement word.

10. The method of claim 1, further comprising using an error correction coding for protecting the acknowledgement word.

11. The method of claim 1, further comprising:

receiving the acknowledgement word at an at least one of the second communication stations;

at the at least one of the second communication stations, examining a bit(s) of the acknowledgement word corresponding to the respectively assigned channel to determine success or failure of the first communication station to receive a data packet transmitted by the at least one of the second communication stations to the first communication station.

12. A communication station comprising:

a channel assignment manager configured to assign respective communication channels to each of plural terminals;

a transceiver configured to transmit channel assignments to the plural terminals and to receive data packets from the plural terminals on the respective communication channels;

a packet error checker configured to perform a packet error check for the data packets received from the plural terminals;

an acknowledgement unit configured to prepare a multi-bit acknowledgement word in accordance with results of the packet error check, for each received data packet the acknowledgement unit being configured to set an associated bit of the acknowledgement word whereby the acknowledgement word has respective bits set for plural ones of the terminals; and

wherein the transceiver is configured to transmit the acknowledgement word to the plural terminals.

13. The apparatus of claim 12, wherein the acknowledgement unit is configured to set the associated bit in association with a particular channel and packet position on the channel.

14. The apparatus of claim 12, wherein the communication station is a cellular base station of a cellular network and the terminals are wireless terminals.

15. The apparatus of claim 12, wherein the channel assignments comprise an assignment of at least one of:

radio channel frequency;

a group of one or more timeslots in a time division multiplex frame;

a duration of the channel assignment;

a number of packets that may be transmitted using the channel assignment;

one or more Code Division Multiple Access codes;

a modulation and coding scheme to use for transmitting a packet;

an assignment of packet size.

16. The apparatus of claim 12, wherein the packet error checker, in performing the packet error check, is configured to use an identifier of the terminal that was assigned the channel on which the packet was received.

17. The apparatus of claim 16, wherein the packet error checker, in performing the packet error check, is configured to use appending the identifier of the terminal to data bits of the received packet and to determine a cyclic redundancy check code over the identifier and the data bits of the received packet.

18. The apparatus of claim 12, further comprising a compressor configured to reduce a number of bits of the acknowledgement word.

19. The apparatus of claim 12, further comprising an error correction unit configured to code the acknowledgement word.

20. A communications terminal comprising:

a transceiver configured to transmit a data packet on an assigned channel to a communication station and to received a multi-bit acknowledgement word from the communication station, the acknowledgement word including at least one bit set for indicating success or failure of the communication station to receive the data packet from the communications terminal and other bits set for at least one other communications terminal;

an acknowledgement word checker configured to determine, in accordance with the channel assigned to the communications terminal, which bit of the acknowledgement word to examine as the at least one bit and further configured to examine the at least one bit to determine the success or the failure of the communication station to receive the data packet.

21. The apparatus of claim 20, further comprising a packet preparer configured to form the data packet by appending a terminal checking code to data bits of the data packet, the terminal checking code comprising a cyclic redundancy check code formed over the data bits of the data packet and a terminal identifier.

22. The apparatus of claim 20, wherein upon the acknowledgement word checker determining the failure of the communication station to receive the data packet, the transceiver is further configured to retransmit the data packet when a suitable opportunity arises.

23. The apparatus of claim 22, wherein the transceiver is further configured to retransmit the data packet upon receiving a request for retransmission from the communications station.

24. The apparatus of claim 22, wherein the transceiver is further configured to retransmit the data packet upon receiving a new channel assignment from the communications station.

25. A method of acknowledging a data packet received by a first communication station from at least one of plural second communication stations, the method comprising:

the first communication station informing the second communication stations of respective channel assignments for the second communication stations;

the at least one of the second communication stations forming a data packet by appending a terminal checking code to data bits of the data packet, the terminal checking code comprising a cyclic redundancy check code formed over the data bits of the data packet and a terminal identifier of the at least one of the second communication stations;

the at least one of the second communication stations using its respectively assigned channel for transmitting the data packet to the first communication station;

receiving the data packet at the first communication station; and

,

performing a packet error check at the first communication station for the data packet received from the at least one of the second communication stations by using the terminal identifier.

26. The method of claim 25, wherein the act of performing a packet error check at the first communication station for the data packet received from the at least one of the second communication stations comprises:

determining the channel upon which the data packet was received;

fetching an expected terminal identifier corresponding to the channel upon which the data packet was received;

determining a cyclic redundancy check code over the data bits of the data packet and the expected terminal identifier; and

comparing the cyclic redundancy check code received in the data packet with the cyclic redundancy check code determined using the expected terminal identifier to determine failure or success of reception of the data packet.

27. A communication station comprising:

a channel assignment manager configured to assign respective communication channels to each of plural terminals and to associate an anticipated terminal identifier to at least one of the communication channels;

a transceiver configured to transmit channel assignments to the plural terminals and to receive data packets from the plural terminals on the respective communication channels;

a packet error checker configured to perform a packet error check for a data packet received from at least one of the plural terminals using an anticipated terminal checking code, the anticipated terminal checking code comprising a cyclic redundancy check code formed over the data bits of the received data packet and the anticipated terminal identifier associated with communication channel on which the data packet is received.

28. The node of claim 27, wherein the packet error checker is further configured to compare the anticipated terminal checking code with an actual terminal checking code, the actual terminal checking code being a cyclic redundancy code received in the received data packet.

29. A communications terminal comprising:

a transceiver configured to transmit a data packet on an assigned channel to a communication station;

a packet preparer configured to form the data packet by appending a terminal checking code to data bits of the data packet, the terminal checking code comprising a cyclic redundancy check code formed over the data bits of the data packet and a terminal identifier of the terminal.

30. The apparatus of claim 29, further comprising an acknowledgement word checker configured to determine, in accordance with the channel assigned to the terminal, which bit of a multi-bit acknowledgement word to examine to determine the success or the failure of the communication station to receive the data packet.