设计了一种连续监测胃肠道生理参数的低功耗参数遥测胶囊, 它主要包括传感器模块、低功耗专用集成芯片和无线射频模块。首先, 采用三态时钟管理单元为集成芯片内部的各个模块选择合适的时钟频率, 并在模块闲置时关闭相应模块的时钟来降低集成芯片的功耗。其次, 采用单工通讯、数据暂存和减小发射功率等方法降低射频模块的功耗。最后, 通过软件设计使胶囊间歇工作以降低系统整体功耗。测试结果表明：专用集成芯片工作时电流约为300 μA@2 MHz, 休眠时约为4 μA@28 kHz; 射频模块发射时电流约为12 mA, 单片机采集数据时电流约为300 μA。与第二代参数胶囊相比, 射频模块和单片机的功耗分别降低了约47%和24%, 可连续工作时间达到136 h, 基本满足参数胶囊长时连续监测胃肠道生理参数的要求。

A low power consumption telemetry capsule was designed for monitoring the gastrointestinal tract’s parameters in long-term and continuation. The capsule consisted of a sensor module, a low power consumption special integrated chip and a wireless emission module mainly. First, to reduce the integrated chip power consumption, a three-state clock management unit was used to choose the appropriate clock frequency for the internal modules of the integrated chip and to shut down the clocks of correcting idle modules. Then, the simplex communication, data temporary storage, reducing transmitting power, etc, were used to reduce the power consumption of the RF module. Finally, the capsule was controlled at work intermittently by the software to reduce the system overall power consumption. Test results show that the work current of the special integrated chip is about 300 μ A @ 2 MH and its dormancy current is about 4 μ A @ 28 kHz. Furthermore, the emission current from the RF module is about 12 mA, and the current of collecting data by a microcontroller is about 300 μ A. As compared with the second generation parameter capsule, the power consumptions of the RF module and the microcontroller are reduced by about 47% and 24% , respectively, and the work time is about 136 h continuously, which basically meets the demands of the capsules for monitoring the gastrointestinal tract’s parameters in long-term and continuation.