Cross-layer QoS analysis of opportunistic OFDM-TDMA and OFDMA networks

Yu Jung Chang*, Feng-Tsun Chien, C. C. Jay Kuo

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

44 Scopus citations


Performance analysis of multiuser orthogonal frequency division multiplexing (OFDM-TDMA) and orthogonal frequency division multiple access (OFDMA) networks in support of multimedia transmission is conducted in this work. We take a cross-layer approach and analyze several quality-of-service (QoS) measures that include the bit rate and the bit error rate (BER) in the physical layer, and packet average throughput/delay and packet maximum delay in the link layer. We adopt a cross-layer QoS framework similar to that in IEEE 802.16, where service classification, flow control and opportunistic scheduling with different subcarrier/bit allocation schemes are implemented. In the analysis, the Kayleigh fading channel in the link layer is modeled by a finite-state Markov chain, and the channel state information (CSI) is assumed to be available at the base station. With the M/G/1 queueing model and flow control results, our analysis provides important insights into the performance difference of these two multiaccess systems. The derived analytical results are verified by extensive computer simulation. It is demonstrated by analysis and simulation that OFDMA outperforms OFDMTDMA in QoS metrics of interest. Thus, OFDMA has higher potential than OFDM-TDMA in supporting multimedia services.

Original languageEnglish
Pages (from-to)657-666
Number of pages10
JournalIEEE Journal on Selected Areas in Communications
Issue number4
StatePublished - 1 May 2007


  • Cross-layer analysis
  • Multiple access
  • OFDM
  • Opportunistic scheduling
  • Quality of services (QoS)

Fingerprint Dive into the research topics of 'Cross-layer QoS analysis of opportunistic OFDM-TDMA and OFDMA networks'. Together they form a unique fingerprint.

Cite this