Wireless network with a plurality of persistency probabilities for accessing a RACH channel

• US 7,161,952 B1
• Filed: 09/15/2000
• Issued: 01/09/2007
• Est. Priority Date: 09/20/1999
• Status: Expired due to Term

• Current Assignee: Atreus Labs LLC
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Herrmann, Christoph
• Primary Examiner(s): Vu, Huy D.
• Assistant Examiner(s): NG, CHRISTINE Y
• Application Number:
  US09/663,315
• Time in Patent Office: 2,307 Days
• Field of Search: 370/322, 370/337, 370/347, 370/348, 370/447, 370/448, 370/461, 370/462, 370/329
• US Class Current: 370/462
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 74/0866 using a dedicated channel for access

Abstract

A wireless network employs at least a base station and a plurality of assigned terminals for exchanging user data and control data. The terminals are each provided for transmitting a reservation message depending on a first persistency probability for assigning transmission capacity for at least one data packet to the assigned base station. Any further transmission of the reservation message received at least once by the base station depends on a different persistency probability.

Claims

1. A wireless network comprising:

a base station; and

a terminal for exchanging user data and control data with the base station in dependence upon a plurality of persistency probabilities for assigning various transmissions capacities by the base station for at least one data packet,

wherein the terminal is operable to transmit a first reservation request for a first time to the base station in dependence on a first persistency probability, the first reservation request being associated with a first data packet, further wherein the base station sends the first persistency probability periodically over a broadcast channel,

wherein, only after a transmission of a rejection message sent by the base station over the broadcast channel corresponding to the first reservation request, the terminal is further operable to transmit the first reservation request for at least one additional time to the base station in dependence on a second persistency probability, wherein the rejection message is linked to a rejected preamble of the respective reservation request such that the second persistency probability is determined differently depending on the rejected preamble, and further wherein the base station sends the second persistency probability non-periodically, different from the first persistency probability, so as not to use a capacity of the broadcast channel unnecessarily,

wherein, during a defined space of time after a complete transmission of the first data packet by the terminal to the base station, the terminal is further operable to transmit a second reservation request in dependence on a third persistency probability, the second reservation request being associated with a second data packet, further wherein the base station sends the third persistency probability periodically over the broadcast channel, and

wherein, in response to the terminal neither receiving an assignment message nor the rejection message corresponding to the first reservation request from the base station after a step-by-step increase of a transmission power to a maximum value by the terminal over at least two transmissions of the first reservation request by the terminal to the base station, the terminal is further operable to transmit the first reservation request for at least one additional time to the base station in dependence of a fourth persistency probability, further wherein the base station sends the fourth persistency probability periodically over the broadcast channel.

2. The wireless network of claim 1,

wherein the first data packet includes a preamble part;

and

wherein the terminal is operable to transmit the preamble part as the first reservation request.

3. The wireless network of claim 1,

wherein the first data packet includes a data part;

and

wherein, after receiving an assignment message corresponding to the first reservation request from the base station, the terminal is further operable to transmit the data part to the base station.

4. The wireless network of claim 1, wherein the terminal is further operable to transmit the first reservation request for the first time to the base station in further dependence of a first comparison of the first persistency probability and a first random number.

5. The wireless network of claim 4, wherein the terminal is further operable to transmit the first reservation request for an additional time to the base station in further dependence of a second comparison of the second persistency probability and a second random number.

6. The wireless network of claim 4, wherein the terminal is further operable to transmit the first reservation request for an additional time to the base station in further dependence of a second comparison of the fourth persistency probability and a second random number.

7. The wireless network of claim 4, wherein the terminal is further operable to transmit the second reservation request to the base station in further dependence of a second comparison of the third persistency probability and a second random number.

8. A base station in a wireless network including a plurality of terminals, the plurality of terminals including at least a first terminal for exchanging user data and control data with the base station in dependence upon a plurality of persistency probabilities for assigning various transmissions capacities for at least one data packet, the base station comprising:

means for periodically transmitting a first persistency probability over a broadcast channel to the plurality of terminals whereby the first terminal is operable to transmit a first reservation request for a first time to the base station in dependence on the first persistency probability, the first reservation request being associated with a first data packet;

means, subsequent to a transmission of the first reservation request for the first time by the first terminal to the base station and only after a transmission of a rejection message sent by the base station over the broadcast channel so as not to use a capacity of the broadcast channel unnecessarily, for non-periodically transmitting a second persistency probability to the plurality of terminals, whereby the first terminal is further operable to transmit the first reservation request for an additional time in dependence of the second persistency probability, wherein the rejection message is linked to a rejected preamble of the respective reservation request such that the second persistency probability is determined differently depending on the rejected preamble; and

means for periodically transmitting at least one of a third persistency probability and a fourth persistency probability to the plurality of terminals whereby the first terminal is further operable to transmit a second reservation request in dependence on the third persistency probability during a defined space of time after a complete transmission of the first data packet by the terminal to the base station, the second reservation request being associated with a second data packet and further operable to transmit the first reservation request for at least one additional time to the base station in dependence on the fourth persistency probability in response to the terminal neither receiving an assignment message nor the rejection message corresponding to the first reservation request from the base station after a step-by-step increase of a transmission power to a maximum value by the first terminal over at least two transmissions of the first reservation request.

9. A terminal in a wireless network including a base station for exchanging user data and control data with the terminal in dependence upon a plurality of persistency probabilities for assigning various transmissions capacities by the base station for at least one data packet, the terminal comprising:

means for transmitting a first reservation request for a first time to the base station in dependence on a first persistency probability, the first persistency probability being periodically transmitted by the base station over a broadcast channel, and the first reservation request being associated with a first data packet;

means, subsequent to a transmission of the first reservation request for the first time by the terminal to the base station and only after a transmission of a rejection message sent by the base station over the broadcast channel so as not to use a capacity of the broadcast channel unnecessarily, for transmitting the first reservation request for an additional time in dependence of a second persistency probability, the second persistency probability being non-periodically transmitted by the base station over the broadcast channel, wherein the rejection message is linked to a rejected preamble of the respective reservation request such that the second persistency probability is determined differently depending on the rejected preamble;

means, during a defined space of time after a complete transmission of the first data packet by the terminal to the base station, for transmitting a second reservation request in dependence on a third persistency probability, the third persistency probability being periodically transmitted by the base station over the broadcast channel and the second reservation request being associated with a second data packet; and

means, responsive to the terminal neither receiving an assignment message nor the rejection message corresponding to the first reservation request from the base station after a step-by-step increase of a transmission power to a maximum value by the terminal over at least two transmissions of the first reservation request, for transmitting the first reservation request for at least one additional time to the base station in dependence on the fourth persistency probability, the fourth persistency probability being periodically transmitted by the base station over the broadcast channel.