Quality of service cognizant scheduler for femtocell base stations

• US 8,594,132 B2
• Filed: 05/17/2011
• Issued: 11/26/2013
• Est. Priority Date: 05/17/2011
• Status: Expired due to Fees

• Current Assignee: Argela Yazilim Ve Bilisim Teknolojileri San. Ve Tic A.S.
• Original Assignee: Argela Yazilim Ve Bilisim Teknolojileri San. Ve Tic A.S.
• Inventors: Kaytaz, Bulent, Sunay, M Oguz
• Primary Examiner(s): Shah, Chirag
• Assistant Examiner(s): PANCHOLI, RINA C
• Application Number:
  US13/109,568
• Publication Number:
  US 20120294161A1
• Time in Patent Office: 924 Days
• Field of Search: None
• US Class Current: 370/477
• CPC Class Codes: H04W 72/543 based on requested quality, e.g. QoS
• CPC Class Codes: H04W 72/566 of the information or information source or recipient
• CPC Class Codes: H04W 72/569 of the traffic information
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B

Abstract

A method and system are provided to schedule the transmissions to a plurality of applications for a plurality of users connected to a femtocell taking into account the quality of service (QoS) requirements of each application served while maintaining an efficient use of the wireless radio resources as well as a user and application weighted notion of fairness of service reception. The scheduler differentiates between not only different users but also between applications of each user, and schedules data transmission amongst these applications so that QoS requirements for all applications are satisfied.

Claims

1. A scheduling method for a femtocell base station in a cellular communication system including the femtocell base station and at least one mobile station connected to the femtocell base station, said mobile station running a plurality of applications, the method as implemented in said femtocell base station comprising the steps of:

receiving data packets at said femtocell base station in said cellular communication system;

differentiating each of said received data packets based on its destination address and an associated application among said plurality of applications;

for each destination address, placing packets of each application in separate buffers, wherein applications are scheduled and one or more of the following system resources are allocated amongst scheduled applications;

femtocell base station transmit power, transmission code space, antennas when said femtocell base station is equipped with multiple antennas, and available bandwidth, such that the following are jointly maximized using multiple objective optimization;

goals of satisfaction of Quality of Service (QoS) requirements of each active application served by said femtocell base station, user and application priority level scaled fairness of service, and sum throughput of said femtocell base station;

transmitting head-of-line packets from each scheduled applications'"'"' buffer over a next transmission period; and

updating QoS requirements, current QoS satisfaction/dissatisfaction levels, observed and average channel qualities for a user, and average observed data rates for each application in time for a next scheduling decision.

2. The scheduling method of claim 1, wherein said cellular system is any of the following:

a CDMA based system, an FDMA based system, or an OFDMA based system.

3. The scheduling method of claim 1, wherein said destination address corresponds to a mobile user.

4. The scheduling method of claim 1, wherein said step of updating QoS requirements comprises updating any of, or a combination of, the following:

maximum instantaneous and average data rates, minimum instantaneous and average data rates, average and maximum packet delays, estimated buffer fullness levels at user end, accurate buffer fullness level at user based on received feedback.

5. The scheduling method of claim 1, wherein said QoS satisfaction/dissatisfaction levels are measured using any of the following:

a token counter, a satisfaction/dissatisfaction metric, or a metric measuring the deviation from a desired level.

6. The scheduling method of claim 1, wherein the femtocell base station schedules and allocates resources amongst plurality of active applications by calculating an application rank for each active application at each scheduling interval based on a nonlinear function of one or more of:

its QoS requirements, its current QoS satisfaction/dissatisfaction levels, its observed channel qualities for a corresponding user, and average channel qualities for each application.

7. The scheduling method of claim 1, wherein user and application priority levels and/or minimum QoS parameter settings for the traffic of different users and/or traffic of different applications are set locally via a user interface.

8. The scheduling method of claim 7, wherein settings changed via said user interface are altered for a given period of time, after which settings return to their previous state.

9. The scheduling method of claim 1, wherein user and application priority levels and/or minimum QoS parameter settings for the traffic of different users and/or traffic of different applications are set based on previously entered data in a calendar program.

10. A scheduling apparatus for a femtocell base station, in a cellular communication system including the femtocell base station and at least one mobile station connected to the femtocell base station, said mobile station running at least two applications, the apparatus comprising,

a plurality of buffers, each buffer storing data destined for a different active application or application type for each active user;

a channel quality collector logic that receives instantaneous channel quality indicators from each active user prior to each scheduling interval and keeps track of average channel quality for each active user and average observed data rate for each active application of each active user where averaging is handled using a sliding window over a pre-defined duration of time;

a user and application fairness logic that keeps a record of current QoS requirements of all active applications, as well as current satisfaction/dissatisfaction levels for QoS requirements of all applications, wherein a cellular operator or an owner of the femtocell set priority levels of all active users and applications or application types; and

a scheduler for determining application rank of each active application and determining how system resources are divided amongst plurality of scheduled applications using a pre-determined scheduling algorithm;

wherein applications are scheduled and one or more of the following system resources are allocated amongst scheduled applications;

femtocell base station transmit power, transmission code space, antennas when said femtocell base station is equipped with multiple antennas, and available bandwidth, such that the following are jointly maximized using multiple objective optimization;

goals of satisfaction of Quality of Service (QoS) requirements of each active application served by said femtocell base station, user and application priority level scaled fairness of service, and sum throughput of said femtocell base station.

11. A scheduling method for a femtocell base station in a cellular communication system including the femtocell base station and at least one mobile device connected to the femtocell base station, each said mobile device running a plurality of associated applications or application types, the method as implemented in said femtocell base station comprising the steps of:

receiving data packets;

differentiating each of said received data packets based on said associated applications or application types and said mobile device;

placing said data packets in separate buffers, one for each application or application types;

scheduling transmission of said data packets over a next transmission period to optimize network resource utilization; and

updating network resource utilization parameters used for said optimization for each of said applications or application types for the next scheduling decision;

wherein applications are scheduled and one or more of the following system resources are allocated amongst scheduled applications;

femtocell base station transmit power, transmission code space, antennas when said femtocell base station is equipped with multiple antennas, and available bandwidth, such that the following are jointly maximized using multiple objective optimization;

goals of satisfaction of Quality of Service (QoS) requirements of each active application served by said femtocell base station, user and application priority level scaled fairness of service, and sum throughput of said femtocell base station.