Methods for ensuring medium access in a wireless network

• US 7,499,425 B2
• Filed: 11/08/2002
• Issued: 03/03/2009
• Est. Priority Date: 11/09/2001
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Lim, Wei Lih, Harada, Yasuo, Ohmi, Shinichiro, Yew, Tan Pek
• Primary Examiner(s): Orgad, Edan
• Assistant Examiner(s): Wong, Blanche
• Application Number:
  US10/290,185
• Publication Number:
  US 20030108059A1
• Time in Patent Office: 2,307 Days
• Field of Search: 370/335, 370/442, 370/347, 370/338, 370/319, 370/337, 370/346
• US Class Current: 370/329
• CPC Class Codes: H04L 47/15 in relation to multipoint traffic arrangements for broadcast or multicast in data networks H04L12/18
• CPC Class Codes: H04L 47/24 Traffic characterised by specific attributes, e.g. priority or QoS
• CPC Class Codes: H04L 47/70 Admission control; Resource allocation
• CPC Class Codes: H04L 47/788 Autonomous allocation of resources
• CPC Class Codes: H04L 47/801 Real time traffic
• CPC Class Codes: H04L 47/824 Applicable to portable or mobile terminals
• CPC Class Codes: H04W 28/20 Negotiating bandwidth
• CPC Class Codes: H04W 72/543 based on requested quality, e.g. QoS
• CPC Class Codes: H04W 74/02 Hybrid access

Abstract

An efficient medium dedication schedule is generated. The schedule gives wireless medium an ability to concurrently serve real-time and non real-time application and still be able to maintain the Quality of Service as requested by the real-time application. Furthermore, QoS registration request is delivered in a time bound manner and a time slot is chosen for transmission during controlled contention phase that give lesser collision and higher throughput.

Claims

1. A method for use in a system comprising an access point and a plurality of stations, the method comprising:

periodically broadcasting a control frame, including information specifying contention slots during which a station may transmit a reservation request in contention with other stations, the periodic broadcasting being carried out by the access point;

transmitting a reservation request, which does not include information indicating a required bandwidth, from a station to the access point in the contention slots;

transmitting a permission signal from the access point, which provides a transmission opportunity for the station, in response to a successful receipt of the reservation request from the station; and

transmitting a bandwidth request including the information indicating the required bandwidth, from the station to the access point, during the transmission opportunity, said bandwidth request having a data structure different from that of said reservation request.

2. The method according to claim 1, further comprising:

determining whether transmission is grantable in accordance with the required bandwidth, the determining being carried out by the access point; and

transmitting a response frame to the station, including information representing whether transmission is grantable, the transmitting a response frame being carried out by the access point.

3. The method according to claim 1, wherein the information indicating the required bandwidth included in the bandwidth request is a QoS requirement for transmitting a data stream comprising at least one parameter, the at least one parameter comprising a minimum bandwidth of the data stream, an average bandwidth of the data stream, a maximum bandwidth of the data stream, a maximum latency allowable, a fluctuation of allowable latency, a data packet size, a minimum required interval between the start of two successive time periods during which the station is permitted to transmit the data stream, a maximum required interval between the staff of two successive time periods during which the station is permitted to transmit the data stream, and extra bandwidth required for at least one of a retransmission, a preamble and a protocol overhead.

4. The method according to claim 1, further comprising:

transmitting a notification frame, including information representing a list of identification numbers of respective stations, from which the reservation request is received during the at least one contention slot, the transmitting the notification frame being carried out by the access point.

5. The method according to claim 1, wherein the station transmits the bandwidth request to the access point each time the station is provided with the transmission opportunity.

6. A method for use in a system comprising an access point and a plurality of stations, the method comprising:

periodically broadcasting a control frame from an access point, including information specifying contention slots during which a station may transmit a reservation request in contention with other stations;

transmitting a reservation request, which does not include information indicating a required bandwidth, from a station to the access point at the contention slots;

transmitting a permission signal from the access point, which provides a transmission opportunity to the station in response to a successful receipt of the reservation request transmitted from the station to the access point;

transmitting a bandwidth request to the access point, including the information indicating the required bandwidth, from the station during the transmission opportunity provided by the access point, said bandwidth request having a data structure different from that of said reservation request;

transmitting a notification, including information representing a list of identification numbers of respective stations, from which the reservation request is received during the at least one contention slot, the transmitting the notification being carried out by the access point; and

transmitting the bandwidth request to the access point during a contention-based phase, during which the station detects whether transmission is possible before transmitting the data stream, when an identification number of the station is not included in the list of identification numbers of the notification, the transmitting of the bandwidth request being carried out by the station.

7. A method to be carried out by an access point that is implemented in a system which includes the access point and a plurality of stations, the method comprising:

periodically broadcasting from an access point a control frame to the plurality of stations, including information specifying a contention interval during which a station can transmit a reservation request in contention with at least one other station;

receiving a reservation request, which does not include information indicating a required bandwidth, at the access point from a station in the contention interval;

transmitting a permission signal from the access point to the station, which provides a transmission opportunity for the station, in response to a successful receipt of the reservation request from the station to the access point; and

receiving a bandwidth request, including the information indicating the required bandwidth, at the access point from the station during the transmission opportunity, said bandwidth request having a data structure different from that of said reservation request.

8. The method according to claim 7, wherein the access point receives the bandwidth request from the station each time the station is provided with the transmission opportunity.

9. A method to be carried out by a station that is implemented in a system comprising an access point and a plurality of stations, the method comprising:

receiving a control frame at a station, including information specifying a contention interval during which the station may transmit a reservation request in contention with at least one other station, the control frame being periodically broadcast by the access point;

transmitting a reservation request, which does not include information indicating a required bandwidth, from the station to the access point in the contention interval;

receiving a permission signal from the access point at the station, that provides a transmission opportunity, in response to a successful receipt of the reservation request transmitted from the station; and

transmitting a bandwidth request, including the information indicating the required bandwidth, from the station to the access point during the transmission opportunity, said bandwidth request having a data structure different from that of said reservation request.

10. The method according to claim 9, wherein the station transmits the bandwidth request to the access point each time the station is provided with the transmission opportunity.

11. An access point for implementation in a system comprising the access point and a plurality of stations, the access point comprising:

a control frame transmitting section configured to periodically broadcast a control frame, including information specifying a contention interval in which a station, may transmit a reservation request in contention with at least one other station;

a reservation request receiving section configured to receive a reservation request, which does not include information indicating a required bandwidth, transmitted from the station in the contention interval;

a permission signal transmitting section configured to provide the station with a transmission opportunity in response to a successful receipt of the reservation request from the station; and

a bandwidth request receiving section configured to receive a bandwidth request transmitted from the station during the transmission opportunity, the bandwidth request including the information indicating the required bandwidth, said bandwidth request having a data structure different from that of said reservation request.

12. The access point according to claim 11, wherein the information indicating the required bandwidth included in the bandwidth request is a QoS requirement for transmitting a data stream comprising at least one parameter, the at least one parameter comprising a minimum bandwidth of the data stream, an average bandwidth of the data stream, a maximum bandwidth of the data stream, a maximum latency allowable, a fluctuation of allowable latency, a data packet size, a minimum required interval between the start of two successive time periods during which the station is permitted to transmit the data stream, a maximum required interval between the start of two successive time periods during which the station is permitted to transmit the data stream, and extra bandwidth required for at least one of a retransmission, a preamble and a protocol overhead.

13. The access point according to claim 11, wherein the bandwidth request receiving section is configured to receive the bandwidth request from the station each time the station is provided with the transmission opportunity.

14. A station for implementation in a system comprising an access point and a plurality of stations, the station comprising:

a control frame receiving section configured to receive a control frame periodically broadcast by the access point, the control frame including information specifying a contention interval during which the station may transmit a reservation request in contention with at least one other station;

a reservation request transmitting section configured to transmit a reservation request, which does not include information indicating a required bandwidth, to the access point in the contention interval;

a permission signal receiving section configured to receive a permission signal which gives a transmission opportunity provided by the access point in response to a successful receipt of the reservation request transmitted from the station; and

a bandwidth request transmitting section configured to transmit a bandwidth request, including the information indicating the required bandwidth, to the access point during the transmission opportunity provided by the access point, said bandwidth request having a data structure different from that of said reservation request.

15. A station according to claim 14, wherein the information indicating the required bandwidth included in the bandwidth request is a QoS requirement for transmitting a data stream comprising at least one parameter, the at least one parameter comprising a minimum bandwidth of the data stream, an average bandwidth of the data stream, a maximum bandwidth of the data stream, a maximum latency allowable, a fluctuation of allowable latency, a data packet size, a minimum required interval between the start of two successive time periods during which the station is permitted to transmit the data stream, a maximum required interval between the start of two successive time periods during which the station is permitted to transmit the data stream, and extra bandwidth required for at least one of a retransmission, a preamble and a protocol overhead.

16. The station according to claim 14, wherein the bandwidth request transmitting section is configured to transmit the bandwidth request to the access point each time the permission signal receiving section is provided with the permission signal, representing the transmission opportunity.