2 : 2.4GHz (Junghoon Paik et al.: Medium to Long Range Wireless Video Transmission Scheme in 2.4GHz Band with Beamforming) (Regular Paper) 23 5, 2018 9 (JBE Vol. 23, No. 5, September 2018) https://doi.org/10.5909/jbe.2018.23.5.693 ISSN 2287-9137 (Online) ISSN 1226-7953 (Print) 2.4GHz a), b), b) Medium to Long Range Wireless Video Transmission Scheme in 2.4GHz Band with Beamforming Junghoon Paik a), Namho Kim b), and Minki Jee b) 2.4GHz km (Beamforming). 3.6km 4 5dBi 16dBm -77dBm 32Mbps., 20km 4 5dBi 10~12Mbps. Abstract In this paper, we propose a wireless video transmission scheme, providing medium and long range communication in the 2.4GHz band with beamforming. With this scheme, it is shown that the transmission rate of 32Mbps and received signal power of -77dBm is achieved with 4 antennas of 5dBi and 16dBm transmit power at each antenna connection for the distance of 3.6km. The scheme also provides transmission distance of 20km for 10~12Mbps with the 4 omni-directional antennas of 5dBi. Keyword : wireless video transmission, medium and long communication distance, beamforming, modulation and coding scheme a) (Department of Broadcasting Technology, Dong-Ah Institute of Media and Arts) b) (Wiznova) Corresponding Author : (Junghoon Paik) E-mail: jhpaik@daum.net Tel: +82-31-670-6734 ORCID: http://orcid.org/0000-0003-2022-1487 Manuscript received August 3, 2018; Revised September 10, 2018; Accepted September 10, 2018..,, Copyright 2016 Korean Institute of Broadcast and Media Engineers. All rights reserved. This is an Open-Access article distributed under the terms of the Creative Commons BY-NC-ND (http://creativecommons.org/licenses/by-nc-nd/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited and not altered.
(JBE Vol. 23, No. 5, September 2018) [1]., [2]-[3]. WiFi, LTE(Long Term Evolution) (cellular), ATSC(Advanced Television System Committee) DVB-T(Digital Video Broadcasting-Terrestrial). WiFi, [4]-[6]. [7]. WiFi. 2.4GHz. II, III. IV V.. 1. 2.4GHz 1. 2.4GHz FPGA. (Ethernet) MAC(Medium Access Control) (Physical) FPGA (Field Programmable Gate Array) RF(Radio Frequency). 1 Ethernet PHY Ethernet MAC MAC Ethernet MAC Ethernet PHY, Ethernet PHY. DMA(Direct Memory Access) CPU PHY ADC/ DAC RF Beam Former Memory MAC Ethernet PHY PHY Ethernet MAC MAC DMA 1. 2.4GHz Fig. 1. Block Diagram of2.48ghz Wireless Modem
2 : 2.4GHz (Junghoon Paik et al.: Medium to Long Range Wireless Video Transmission Scheme in 2.4GHz Band with Beamforming) Ethernet MAC Ethernet MAC. Beam Former. 2 2.4GHz. 2. 2.4GHz Fig. 2. 2.4GHz Wireless Modem 1.1 3. MAC Scrambler (Randomize) Convolutional encoder Interleaver. Mapper. IFFT(Inverse Fast Fourier Transformer) CP insert cycle prefix. 1.2 4. Ca- rrier sense. Gain control. CFO (Carrier Frequency Offset) estimation CFO correct. Symbol sync, Window FFT(Fast Fourier Transformer). FFT. Phase track (pilot). Demapper, Deinterleaver. Viterbi decoder, Descrambler MAC. 1.3. 5.,. 3. Fig. 3. Structure of Modem Transmit Part 4. Fig. 4. Structure of Modem Receive Part
(JBE Vol. 23, No. 5, September 2018). III. 1. 7. 2.412GHz 20MHz. 5. Fig. 5. Structure of Beam-forming Part 6. Receive Trainning Symbol Transmit Trainning Symbol Estimated Beam Request of Trainning Symbol Trainning Symbol 6. Fig. 6. Beam-forming Process Estimated Beam.... 7. Fig. 7. Frequency Spectrum of Transmit Signal 2. 1 (Error vector magnitude) Phase track. 1. Table 1. Error vector magnitude of receive signal Modulation EVM (db) QPSK -20.08 16QAM -22.6 64QAM -23.08 8 64QAM.
백정훈 외 인 빔 형성을 적용한 대역 중장거리 영상 전송 무선 기술 697 2 : 2.4GHz (Junghoon Paik et al.: Medium to Long Range Wireless Video Transmission Scheme in 2.4GHz Band with Beamforming) 제어 신호는 0Ch이고, 두 번째 빔 훈련 신호의 빔 제어 신호는 18h등 이다. 빔 제어 신호 20h의 경우 수신 신호의 크기가 매우 작은 반면에 빔 제어 신호 00h에서 수신 신호 가 가장 큰 것을 확인할 수 있다. 즉 송신 신호의 빔 방향에 따라 수신신호의 크기가 변하는 것을 확인할 수 있다. 그림 8. 64QAM 복조신호의 EVM A Fig. 8. EVM of 64QAM Demodulated Signal 그림 9는 64QAM 복조 신호의 성상도를 나타낸다. B 그림 10. 송신 빔 형성 Fig. 10. Transmit Beam Forming 수신기의 빔 제어 신호를 변화 시키면서 관찰한 기저 대 역에서의 수신 신호의 크기는 그림 11과 같다. 수신 신호와 송신 신호는 각각 신호A와 신호B로 표시되며 수신기의 빔 제어 신호는 수신신호 상위에 겹쳐진 형태로 표시된다. 수 신기는 네 개의 안테나를 사용하여 빔 형성을 시도하고, 송 신기는 하나의 안테나를 사용함으로서 빔 형성을 사용하지 않는다. 수신기의 빔 방향에 따라 수신된 신호의 크기가 변 그림 9. 64QAM 복조신호의 성상도 Fig. 9. Constellation of 64QAM Demodulated Signal 3. 빔 형성 A 그림 10은 송신 안테나의 빔을 변화 시키면서 관찰된 수 신기에서의 기저 대역 신호의 크기를 보여준다. 신호A와 B 신호B는 각각 수신기의 기저대역 신호와 송신기의 기저 대 역 신호를 나타내고 신호A와 신호B 사이의 신호는 송신기 의 빔 제어 신호를 의미한다. 빔 훈련 신호에 앞서 송신되는 그림 11. 수신 빔 형성 신호는 빔 제어 신호 00h이고, 첫 번째 빔 훈련 신호의 빔 Fig. 11. Receive Beam Forming
(JBE Vol. 23, No. 5, September 2018). IV. 12 3.6km. 5dBi 16dBm. 13. 3.6km Fig. 13. Transmission rate for transmit distance of 3.6km 12. 3.6km Fig. 12. 3.6km Outdoor Transmission Test 13 3.6km. 31.7Mbps. 14 20km. 4 5dBi (omni). 14. 20km Fig. 14. 20km Outdoor Transmission Test 15. 20km Fig. 15. Transmission rate for transmit distance of 20km
2 : 2.4GHz (Junghoon Paik et al.: Medium to Long Range Wireless Video Transmission Scheme in 2.4GHz Band with Beamforming) 15 20km. 10~12 Mbps. V. 2.4GHz. 3.6km 4 5dBi 16dBm -77dBm 32Mbps., 20km 4 5dBi 10~12Mbps. (References) [1] Myung Chul Park and Dong Seog Han, Analysis of Spatial Modulation MIMO Reception Performance for UHDTV Broadcasting, Journal of Broadcast Engineering, Vol.20, No.6, pp.837-847, Nov. 2015. [2] Bong Gyun Jo and Dong Seog Han, Performance Analysis and Design of MIMO Systems for Terrestrial Transmission of UHDTV, Journal of Broadcast Engineering, Vol.15, No.4, pp.547-554, Nov. 2010. [3] Woon Hyun Lee, Jeongchang Kim, Sung Ik Park, and Namho Hur, Study on 2 2 MIMO Detection in ATSC 3.0 Systems, Journal of Broadcast Engineering, Vol.22, No.6, pp.755-764, Dec. 2017. [4] Kenneth Wyatt, Wi-Fi network interference, analysis, and optimization, EDN NETWORK, Feb. 2015, https://www.edn.com/elec- tronics-blogs/the-emc-blog/4438663/wi-fi-network-interference-- analysis--and-optimization [5] Zhiyuan Weng, Philip V. Orlik, and Kyeong Jim Kim, Classification of Wireless Interference on 2.4GHz Spectrum, Proceedings of 2014 IEEE Wireless Communications and Networking Conference(WCNC), Istanbul, Turkey, pp.786-791, April 2014. [6] Iwona Dolińska, Mariusz Jakubowski, and Antoni Masiukiewicz, Interference comparison in Wi-Fi 2.4 GHz and 5 GHz bands, 2017 International Conference on Information and Digital Technologies (IDT), pp.106-112, July 2017. [7] Victor M. Dionisio and Cristiano Akamine, Comparision of Terrestrial DTV Systems: ISDB-T and ATSC3.0, Set International Journal of Broadcast Engineering, Vol. 3, Article 1, pp.8-14, 2017. - 2002 9 ~ : - ORCID : http://orcid.org/0000-0003-2022-1487 - : - 2000 7 ~ : - ORCID : http://orcid.org/0000-0002-0727-5969 - : Hardware Design
(JBE Vol. 23, No. 5, September 2018) - 2011 1 ~ : - ORCID : http://orcid.org/0000-0002-3237-0933 - : MAC(Media Access Control)