OFDMA with variable tone spaces

Sungmook Lim, Gosan Noh, Jihaeng Heo, Hyungjong Kim, Daesik Hong

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)


Next generation wireless networks such as 3GPP LTE-A demand enhanced system capacity for high-quality multimedia services. Carrier aggregation based on OFDMA has been introduced to achieve this. In CA, each component carrier can be located on a different frequency band, and each user utilizing it moves at a different speed. This results in different channel characteristics for each user. Enhancing the system capacity in this environment requires a multiple access scheme that considers different channel characteristics among users. However, conventional OFDMA using fixed tone space (called OFDMA-FTS) does not consider user-specific channel characteristics, resulting in capacity degradation. In this article, we propose a new OFDMA system with variable tone spaces (OFDMA-VTS) as an approach to enhance system capacity. OFDMA-VTS selects the tone space suitable for each user by considering userspecific channel characteristics in CA. When intersymbol interference is dominant due to a long delay spread, the small tone space is selected to eliminate severe ISI. Conversely, when intercarrier interference due to a large Doppler spread severely degrades the system performance, the large tone space is selected to compensate ICI. In the proposed OFDMA-VTS, each user adaptively selects the optimal tone space needed to minimize the total interference of ISI and ICI, therefore enhancing system capacity.

Original languageEnglish
Article number6393526
Pages (from-to)113-120
Number of pages8
JournalIEEE Wireless Communications
Issue number6
Publication statusPublished - 2012

Bibliographical note

Funding Information:
This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea govern ment(MEST) (No. 2010- 0018938).

All Science Journal Classification (ASJC) codes

  • Computer Science Applications
  • Electrical and Electronic Engineering


Dive into the research topics of 'OFDMA with variable tone spaces'. Together they form a unique fingerprint.

Cite this