LTE frequency selective scheduling performance and improvements assessed by measurements

Author

Ökvist, Peter ; Simonsson, Arne ; Asplund, Henrik

Author_Institution

Ericsson Res., Stockholm, Sweden

fYear

2011

fDate

11-14 Sept. 2011

Firstpage

1919

Lastpage

1923

Abstract

In this paper the potential of downlink frequency selective scheduling (FSS) is addressed based on measurements in an experimental 3GPP Long Term Evolution (LTE) system setup. We find that scheduling on the best sub-band has the potential to improve channel conditions by up to 2 Channel Quality Indicator (CQI) units, which represents around 4 dB channel gain improvement. The time-frequency fading characteristics as a function of mobile speed is described and verified in measurements where instances of correlated time-frequency fading are observed. In stationary or semi-stationary scenarios CQI reporting delays are not limiting. However, at a mobile speed of 10 km/h the gain is lost when the reporting delay reaches 20 ms at the studied 2 GHz band. A simple prediction algorithm that utilizes how the best sub-band moves in frequency domain can improve the gain at 10 km/h around one CQI unit (2 dB) for the studied measurements indicating improvement potential for FSS at higher mobile speed.

Keywords

Long Term Evolution; scheduling; 3GPP; CQI; FSS; LTE frequency selective scheduling performance; channel quality indicator units; downlink frequency selective scheduling; frequency 2 GHz; time 10 ms; Delay; Fading; Gain; OFDM; Time frequency analysis; CQI; FSS; LTE; channel characteristics; frequency selective scheduling; prediction;

fLanguage

English

Publisher

ieee

Conference_Titel

Personal Indoor and Mobile Radio Communications (PIMRC), 2011 IEEE 22nd International Symposium on

Conference_Location

Toronto, ON

ISSN

pending

Print_ISBN

978-1-4577-1346-0

Electronic_ISBN

pending

Type

conf

DOI

10.1109/PIMRC.2011.6139844

Filename

6139844