POWER CONTROL ARRANGEMENT FOR LONG TERM EVOLUTION TIME DIVISION DUPLEX METHOD AND APPARATUS

• US 20130136024A1
• Filed: 01/25/2013
• Published: 05/30/2013
• Est. Priority Date: 02/05/2008
• Status: Active Grant

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Nokia Corporation
• Inventors: PAJUKOSKI, Kari Pekka, TIIROLA, Esa Tapani, CHE, Xiang Guang, SKOV, Peter
• Granted Patent: US 8,711,727 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 52/04 TPC
• CPC Class Codes: H04W 52/242 taking into account path loss
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels

Abstract

Embodiments of the present invention provide methods, systems and apparatuses for optimizing downlink path loss (PL) measurements in time division duplex (TDD) systems enabling fast power control targeting to decrease fading margin. In one embodiment, a method of power control in a long term evolution time division duplex (TDD) system is provided. The method includes controlling a length of a path loss measurement filter based on an allocation type. A width and frequency position of the path loss measurement filter is made dependent on the allocation type.

Claims

1. An apparatus comprising:

a controller configured to

measure attenuation from a plurality of sub-bands of a frequency spectrum in which a physical uplink control channel is being transmitted; and

calculate a path loss measurement as an average of the measurement of said attenuation from each of the plurality of sub-bands of the frequency spectrum.

2. The apparatus of claim 1, wherein said controller is a controller in a long term evolution time division duplex system.

3. The apparatus of claim 1, wherein said path loss measurement is calculated using the following formula:

PL=(P₁+P₂ . . . +P_N)/N

where PL is the path loss, and P₁,P₂, . . . P_N are instantaneous channel attenuation measurements from a plurality of sub-bands.

4. The apparatus of claim 1, wherein power control for said physical uplink control channel is calculated using the following formula:

P=min(P_max, 10log10(M)+P_o+α

PL+Δ

_mcs+f(Δ

_i)),

where P_max is a maximum allowed user equipment power, M is a number of assigned resource blocks, α

is a path loss compensation factor, P_o is a cell and user equipment specific scaling parameter, PL is the downlink path loss measured at the user equipment, Δ

_mcs is MCS specific value, and f(Δ

_i) is a user equipment specific closed loop correction value.

5. The apparatus of claim 1, wherein a combined channel attenuation is calculated using the following formula: