應用於人體通道通訊之設計技術

Abstract

近年來，人體近身網路之研究受到越來越多的關注，其應用包含生理遙測監控、可攜式影音電子產品以及互動娛樂等，而人體通道通訊為其中一種系統實現的方式，其概念是利用人體體表當作訊號的傳輸介質，由於人體體表的路徑衰減較小以及較沒有多人使用的互相干擾問題，人體通道傳輸的整體傳輸功耗、資料傳輸量可以有很好的效能。於2007年，IEEE 802.15成立了一個test group (TG6)，針對人體近身網路討論通訊標準規範，而目前的草書中也有部份針對人體通道通訊所使用的頻寬、操作行為做基本的描述。這幾年也有許多相關研究提出，但大多使用簡單的調變方式，且傳輸速度都不高。因此本三年計畫(2011/8~2014/7)首先會參考目前的標準草書，提出適用於生理訊號監測系統的超低功耗傳輸模組以及適用於高速多媒體影音資料交換之傳輸模組。在長時間的生理訊號監控應用當中，穩定的傳輸品質、超低功率消耗、以及配戴舒適度為三大設計考量。針對在人體通道的傳輸品質，適當的調變方式、抗干擾之演算法以及錯誤更正技術都是此計畫之研究重點；在低功耗的訴求之下，我們也將對收發模組架構最佳化以及重要模組實現等關鍵技術做研發；考量長時間配戴舒適度的問題，本計畫亦規劃無石英震盪器之傳收系統以減小系統整合的面積。為了將應用範圍擴展至多媒體影音資料傳輸之情境，本計畫也研究如何提升高資料傳輸率以符合多媒體影音傳輸之應用，在資料傳輸率與電路功耗做最佳化。本計畫將會將研發之傳收模組以及其他關鍵技術，使用FPGA平台進行行為及效能之驗證，並且在最後將系統整合，完成晶片實現。

Body area network (BAN) is an attractive communication scheme for the ubiquitous healthcare systems, portable audio/video systems, and the interactive entertainment systems. Body channel communication (BCC), using the human body as the signal transmission medium, is a possible solution of BAN to achieve robust communication with low energy consumption. In 2007, the IEEE 802.15 Task Group 6 (TG 6) was organized to standardize the frequency band as well as the protocols of medical and multimedia communications around a human body. Moreover, the behavior of BCC is included in the standard draft. The state-of-the-art solutions use simple modulation with low data rate, that achieve neither reliable medical monitoring with multiple sensor nodes coexistence nor other multimedia data exchange applications which require much higher data rate. As a result, in this 3-year (2011/8~2014/7) research proposal, we will refer to the standard draft and propose a high data rate and low power solution for both medical monitoring and multimedia information applications. For the long-duration medical monitoring, the robust transmission, low power consumption and comfortable usage are the critical design issues. To achieve a reliable transmission with multiple sensor nodes environments, the modulation scheme, error correction codes, and other algorithms will be investigated. As considered to the low power requirement, the transceiver architecture and system parameters will be discussed, and key modules and techniques will also be employed. For the comfortable wearing issue, a crystal-less system will be developed to minimize the integrated system area. To extend the application to multimedia data transmission, a trade-off between data rate and power consumption will also be discussed. Enhancing the data rate with minimum power overhead is our key design target. An FPGA prototype will be set up to evaluate the performance of the proposed BCC solution, and finally these designs and key modules will be integrated together and verified by an ASIC chip.