Other Functions

Some details of modulation, framing and deframing, and FFT and IFFT have been discussed in the last chapter. For FEC, as mentioned, we use the encoder and decoder of [20], whose functionality is being further improved.

D. Conclusion

We considered DSP software implementation and integration of key uplink transceiver

functions under the OFDMA TDD mode of transmission of the IEEE 802.16 standards. For efficiency and practicality, the functions were implemented using fixed-point computation.

Some of the functions achieved relatively high efficiency in CPU utilization. A GUI on the PC was also developed for convenience in execution control and display of results. At present, the not yet fully optimized code requires the computing power of some number of DSP chips to perform all the transmitter and receiver functions.

Several areas of the implementation that need improvement have been identified and are either being worked on or considered as potential future work.

六、參考文獻

[1] C.-J. Wu and D. W. Lin, “Sparse channel estimation for OFDM transmission based on representative subspace fitting,” in IEEE 61^st

Veh. Technol. Conf., May 2005.

[2] R.-C. Chen, D. W. Lin, and C.-J. Wu, “Pilot-aided channel estimation for IEEE 802.16 OFDMA TDD downlink transmission and its DSP software implementation,” to appear in Proc. Workshop Consumer Electronics Signal Processing, Yunlin, Taiwan, ROC, Nov. 2005.

[3] R.-C. Chen, “IEEE 802.16a TDD OFDMA downlink pilot-symbol-aided channel estimation: techniques and DSP software implementation,” M.S. thesis, Dept.

Electronics Engineering, National Chiao Tung University, June 2005.

[4] Y.-S. Chen, D. W. Lin, and C.-J. Wu, “DSP Software Implementation and Integration of IEEE 802.16 TDD-OFDMA-mode downlink transceiver functions,” to appear in Proc. Int.

Symp. Commun., Kaohsiung, Taiwan, ROC, Nov. 2005.

[5] Y.-S. Chen, “DSP software implementation and integration of IEEE 802.16a TDD OFDMA downlink transceiver system,” M.S. thesis, Dept. Electronics Engineering, National Chiao Tung University, Hsinchu, Taiwan, R.O.C., June 2005.

[6] C.-C. Tung, D. W. Lin, and C.-J. Wu, “Software implementation and integration of IEEE 802.16 OFDMA-TDD-mode uplink transceiver functions on digital signal processor,” to appear in Proc. Workshop Consumer Electronics Signal Processing, Yunlin, Taiwan, ROC, Nov. 2005.

[7] C.-C. Tung, “IEEE 802.16a OFDMA TDD uplink transceiver system integration and optimization on DSP platform,” M.S. thesis, Dept. Electronics Engineering, National Chiao Tung University, Hsinchu, Taiwan, R.O.C., June 2005.

[8] K.-C. Hung and D. W. Lin, “A hybrid variable step-size adaptive blind equalization algorithm for QAM signals,” to appear in Conf. Rec., IEEE Global Telecommun. Conf., Nov. 2005.

[9] Y.-N. Lin, “Analysis and design of direct-sequence code-division multiple access for wireless communications,” Ph.D. dissertation, Dept. Electronics Engineering, National Chiao Tung University, Hsinchu, Taiwan, ROC, July 2005.

[10] O. Edfors, M. Sandell, J. J. van de Beek, S. K. Wilson, and P. O. Borjesson, “OFDM channel estimation by singular value decomposition,” in IEEE 46th Veh. Technol. Conf., Apr. 1996, pp. 923--927.

[11] S. G. Kang, Y. M. Ha, and E. K. Joo, “`A comparative investigation on channel estimation algorithms for OFDM in mobile communications,” IEEE Trans.

Broadcasting, vol. 49, no. 2, pp. 142--149, June 2003.

[12] H. Minn and V. K. Bhargava, “An investigation into time-domain approach for OFDM channel estimation,” IEEE Trans. Broadcasting, vol. 46, no. 4, pp. 240-248, Dec. 2000.

[13] B. Yang, K. B. Letaief, R. S. Cheng and Z. Cao, “Channel estimation for OFDM

transmission in multipath fading channels based on parametric channel modeling,”

IEEE Trans. Commun., vol. 49, no. 3, pp. 467-478, Mar. 2001.

[14] O. Simeone, Y. Bar-Ness, and U. Spagnolini, “Pilot-based channel estimation for OFDM systems by tracking the delay-subspace,” IEEE Trans. Wireless Commun., vol.

3, no. 1, pp. 315-324, Jan. 2004.

[15] I.-I. Chen, “Study and techniques of IEEE 802.16a TDD OFDMA downlink channel estimation,” M.S. thesis, Dept. Electronics Engineering, National Chiao Tung University, Hsinchu, Taiwan, R.O.C., June 2004.

[16] M.-H. Hsieh, “Synchronization and channel estimation techniques for OFDM systems,” Ph.D. dissertation, Dept. Electronics Engineering, National Chiao Tung University, Hsinchu, Taiwan, R.O.C., May 1998.

[17] M.-T. Lin, “Fixed and mobile wireless communication based on IEEE 802.16a TDD OFDMA: transmission filtering and synchronization,” M.S. thesis, Dept. Electronics Engineering, National Chiao Tung University, June 2003.

[18] T.-S. Chiang, “Study and DSP implementation of IEEE 802.16a TDD OFDM downlink synchronization,” M.S. thesis, Degree Program of Electrical Engineering and Computer Science, National Chiao Tung University, Hsinchu, Taiwan, R.O.C., July 2004.

[19] Texas Instruments, TMS320C64x DSP Library Programmer's Reference. Lit. no.

SPRU565B, Oct. 2003.

[20] Y.-T. Lee, “DSP implementation and optimization of the forward error correction scheme in IEEE 802.16a standard,” M.S. thesis, Dept. Electronics Engineering, National Chiao Tung University, Hsinchu, Taiwan, R.O.C., June 2004.

[21] C.-Y. Chen, “DSP implementation of AMR speech coding and the Reed-Solomon decoder in IEEE 802.16a standard,” M.S. thesis, Dept. Electronics Engineering, National Chiao Tung University, Hsinchu, Taiwan, R.O.C., June 2005.

七、計畫成果自評

研究內容與原計畫相符程度：符合計畫主題，達成之主要成果包括：適用於OFDM

系列傳輸方法之新穎通道估計技術、TDD OFDMA 下行及上行傳收系統功能組件之 DSP 軟體實現與整合、及新穎之快速盲目等化法、等等。

達成預期目標情況：本子計畫達成之貢獻形式，含創新之發現、技術水準之提升、

實驗系統之建立、人才培育(其中在本年度畢業的有一位博士、三位碩士)。

成果之學術與應用價值等：

1. 在學術價值方面，主要成果中，新穎的 OFDM 系列傳輸方法之通道估計技術，

已發表為國際會議論文。正進行後續研究。OFDMA 傳收系統組件之 DSP 軟 體實現與整合，已獲國內會議接受，即將發表。新穎之快速盲目等化法以，已 獲國際會議接受，即將發表。也正在進行其他相關研究。另有其他具學術價值 之成果，在此不一一列舉。

2. 在應用價值方面，以上成果皆可供相關業界參考。部分成果可考慮稍微修改申 請專利。

綜合評估：本計畫獲得一些具有學術與應用價值的成果，並達人才培育之效。成效 良好。

可供推廣之研發成果資料表

□ 可申請專利 ■ 可技術移轉 日期：94 年 7 月 31 日

國科會補助計畫

計畫名稱：無線正交分頻多重進接頻道使用技術研究及全系統整合 (2/2)

計畫主持人：林大衛

計畫編號：NSC 93-2219-E-009-014 學門領域：電信國家型計畫 技術/創作名稱 OFDMA 傳收器組件之 DSP 軟體

發明人/創作人 陳昱昇、董景中、林大衛

中文：基於IEEE 802.16a TDD OFDMA 規範之傳收器功能組件之

DSP 軟體實現，含 modulation、framing and deframing、FFT and IFFT、transmitter and receiver filtering、synchronization、等等。其 中DSP 為 Texas Instruments 之 TMS320C6416，而 FFT 及 IFFT 係 基於Texas Instruments 之 DSPLIB 所提供之一函數。

技術說明

英文：DSP software implementation of transceiver components rooted on the IEEE 802.16a TDD OFDMA specifications. The transceiver functions implemented include modulation, framing and deframing, FFT and IFFT, transmitter and receiver filtering, synchronization, etc.

The DSP used is Texas Instruments’ TMS320C6416, and the FFT and the IFFT functions have been implemented employing a function in the DSPLIB provided by Texas Instruments.

可利用之產業 及 可開發之產品

無線通訊技術研發單位。

技術特點

使用DSP 軟體，實現或模擬 OFDMA 傳收器之功能組件。

推廣及運用的價值

可用於無線通訊設備之研發。

※ 1.每項研發成果請填寫一式二份，一份隨成果報告送繳本會，一份送 貴單位

研發成果推廣單位（如技術移轉中心）。

※ 2.本項研發成果若尚未申請專利，請勿揭露可申請專利之主要內容。

※