感測器所量測的生醫訊號會先後經過數位類比轉換器、電源供應、控制器、數位信號處理器和信號傳送輸出；在無線身體感測網路系統中，尤以長期健康看照為最，以TI Zigbee無線模組為例，其功率損耗為81mW；因此，有超過90%的功率損耗是在無線傳輸部分；降低無線傳輸電路的功率損耗有兩個方法，一是用功率管理，另一則是利用資料壓縮降低傳輸資料量。因此一個新的微控制器設計應用在身體感測網路是為了符合降低功率損耗的要求和增加控制、壓縮和資料傳輸功能。
本論文提出的微控制器具有低成本、低功率損耗以及高效能的特性。此微控制器由非同步介面、暫存器庫、可重置式濾波器、斜率特徵預測電路、無失真資料壓縮、錯誤更正電路、通用非同步收發電路介面(UART)、功率管理電路和多重感測控制器所組成。非同步介面是為了提升不同頻率的訊號交換效能，更進一步提高系統的效率和擴展系統的可塑性；可重置式濾波器是用來降低有效降低生醫訊號的多種雜訊，其中包含低通、帶通和高通三種功能；斜率特徵預測電路和無失真資料壓縮的設計，可有效的降低無線傳輸的資料量，其壓縮率最高可達2.68；而錯誤更正電路的設計可增加無線傳輸的可信度，可將無線傳輸遺失的位元，準確無誤的更正至正確。在長期健康監控系統中，一個功率管理電路的設計，利用工作及睡眠模式的切換，能有效的降低無線身體感測網路系統的功率消耗。
本系統以超大型積體電路(VLSI)實現，並成功將此電路以其中電路可程式邏輯閘陣列(FPGA)發展版驗證；此設計於TSMC0.18μm的CMOS製程下，其邏輯閘數為67-K，且於操作頻率為100MHz時功率損耗為5.8mW；此電路亦以TSMC0.13μm製程實現，操作頻率133MHz的功率損耗則為1.9mW。其中功率管理電路邏輯閘數僅為0.12K，佔整體電路功率損耗不到1.5%；以體溫為例，一般操作下為60分鐘全程開啟；而在功率管理電路的控管下，只需每分鐘開啟一秒，便將資料傳輸完成，此步驟替系統省下97.2%的功率損耗。此外，資料壓縮電路，以ECG資料量為例，每秒有360筆值，每筆值為11個位元數編碼，故一秒的資料量為3960位元碼；加入無失真資料壓縮電路，其壓縮率為2.68，則輸出位元數減至1477位元碼，故可縮短無線傳輸時間，藉以降低無線傳輸的功率損耗。
本論文提出的微控制器矽核設計相較於其他已發表的論文，此設計無論在效能、功能、面積大小與相容性皆有較好的表現，其中以功率管理和資料壓縮的設計，最為有效且顯著降低系統功率損耗。本論文的主要貢獻為，完成設計一個高效率的微處理器矽核設計並提供了一個良好的基礎得以發展無線身體網路系統。

Biomedical signals are measured using bio-sensors, which require an analog-to-digital (ADC) converter, power supplies, a controller, digital signal processor (DSP), and output transmission. More than 90% of the power of wireless body sensor networks (WBSNs) is consumed by the RF Module, especially with long-term healthcare monitoring. Taking the Zigbee wireless module from Texas Instruments (TI) as an example, the power of the module is 81mW. Two ways to reduce the power needed by the RF module are power management and data compression. The current work aims to reduce this power requirement, while also improving the functions of control, compression, and transmission, and thus it presents the design of a new micro control unit (MCU) for a wireless body sensor network (WBSN).
The low-cost, low-power and high performance MCU core proposed in this work consists of an asynchronous interface, a register bank, a reconfigurable filter, a slope-feature forecast function, a lossless data encoder, an error correct coding (ECC) encoder, a UART interface, a power management (PWM) function and a multi-sensor controller. To improve system performance and its ability for expansion, an asynchronous interface is added to handle signal exchanges between different clock domains. In order to eliminate the noise due to various bio-signals, a reconfigurable filter is used to provide average, binomial and sharpen filters. The slope-feature forecast and the lossless data encoder with a top compression rate (CR) of 2.68 are used to reduce the amount of data obtained from the various biomedical signals to short the time of transmission.
The ECC encoder is used to increase the reliability of wireless transmission, while the UART interface enables the proposed design to be compatible with most wireless devices. In addition, for long-term healthcare monitoring, a power management technique is developed in this work to reduce the power consumption of the WBSN system. The proposed design can operate with four different bio-sensors simultaneously, and was successfully tested with an FPGA verification board. The VLSI architecture used in this work contains 7.67-K gate counts and consumes 5.8 mW or 1.9 mW at a 100 MHz or 133 MHz processing rate using a TSMC 0.18 μm or 0.13 μm CMOS process, respectively. The gate count of PWM is 0.12K only, and its power is less than 1.5% of whole MCU design. For example, the power supply used for the device to monitor body temperature is turned on for 60 minutes without any interruption. But with the PWM circuit, the power only needs to be turned on for one second each minute to transmit the data. This reduces the amount of power the WBSN system needs by 97.2%. Furthermore, another example of reduced power consumption is with the ECG signals. The sample rate with the ECG is 360 times per second, and the output is 11 bits per data, which means that the total data of ECG is 3,690 bits per second. However, this decreases to 1,477 bits when the CR 2.68 data compressor used, significantly reducing both the time and power needs to the wireless module.
Compared with previous techniques, the results show that this design achieves higher performance, has more functions, greater flexibility and better compatibility than other micro controller designs. The reduced power consumption is due to better power management and the use of a lossless data compressor. The contribution of this proposed work is that it provides an expandable system for WBSN with an efficient MCU core design.

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