Apparatus and method for mobile assisted adaptive FFR

• US 8,649,338 B2
• Filed: 07/06/2010
• Issued: 02/11/2014
• Est. Priority Date: 07/06/2010
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Vrzic, Sophie, Fong, Mo-Han
• Primary Examiner(s): Nguyen, Thai
• Application Number:
  US12/830,909
• Publication Number:
  US 20120008569A1
• Time in Patent Office: 1,316 Days
• Field of Search: 370/329, 370/337, 370/328, 370/436, 455/450, 455/425
• US Class Current: 370/329
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0032 Distributed allocation, i.e. involving a plurality of allocating devices, each making partial allocation
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0062 Avoidance of ingress interference, e.g. ham radio channels
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04W 16/10 Dynamic resource partitioning
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/241 taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo
• CPC Class Codes: H04W 52/244 Interferences in heterogeneous networks, e.g. among macro and femto or pico cells or other sector / system interference [OSI]
• CPC Class Codes: H04W 52/247 where the output power of a terminal is based on a path parameter sent by another terminal
• CPC Class Codes: H04W 52/248 where transmission power control commands are generated based on a path parameter
• CPC Class Codes: H04W 52/38 TPC being performed in particular situations
• CPC Class Codes: H04W 52/386 centralized, e.g. when the radio network controller or equivalent takes part in the power control
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

In a method of fractional frequency reuse in a communication network, a frequency band is divided into a plurality of sub-bands according to a Fractional Frequency Reuse (FFR) scheme to define a FFR allocation of the band for a plurality of bases stations, each of the base stations being associated with a respective region. At a first base station of the plurality of base stations, the first base station associated with a first region, communication with a mobile terminal in the first region is established on one of the plurality of sub-bands according to the FFR allocation. A second base station of the plurality of base stations, the second base station associated with a second region, transmits on the one of the plurality of sub-bands according to the FFR allocation; receives an indication of a coverage problem detected at the mobile terminal due to interference from the second base station on the one of the plurality of sub-bands; and in response to the receiving the indication, decreases a transmit power level for the one of the plurality of sub-bands in the second region.

Claims

1. A method of fractional frequency reuse in a communication network, said method comprising:

dividing a frequency band into a plurality of sub-bands according to a Fractional Frequency Reuse (FFR) scheme to define a FFR allocation of said band for a plurality of base stations, each of said base stations associated with a respective region;

at a first base station of said plurality of base stations, said first base station associated with a first region;

establishing communication with a mobile terminal in said first region on one of said plurality of sub-bands according to said FFR allocation;

at a second base station of said plurality of base stations, said second base station associated with a second region;

transmitting on said one of said plurality of sub-bands according to said FFR allocation;

receiving an indication of a coverage problem detected at said mobile terminal due to interference from said second base station on said one of said plurality of sub-bands, wherein said indication comprises a difference between the carrier to interference power ratios (CIR) of said first base station and of said second base station as detected by said mobile terminal; and

in response to said receiving said indication, decreasing a transmit power level for said one of said plurality of sub-bands in said second region.

2. The method of claim 1, wherein said defining said FFR allocation comprises:

defining said one of said plurality of sub-bands as a high power sub-band for said first base station, and defining said one of said plurality of sub-bands as a power restricted sub-band for said second base station.

3. The method of claim 1 wherein receiving said indication comprises receiving said indication from said mobile terminal.

4. The method of claim 1 further comprising:

at said first base station, receiving said indication from said mobile terminal and sending said indication to said second base station.

5. The method of claim 1, wherein said indication comprises a command from said mobile terminal to said second base station to decrease said transmit power level for said one of said plurality of sub-bands.

6. The method of claim 1, wherein said communication network is an orthogonal frequency-division multiple access communication network.