## 3 MIGOU Platform
### Design and Implementation
This chip supports transfers of up to 320 Mbps, which is more than enough considering that the LVDS interface between the AT86 RF215 and the SmartFusion2 has a maximum data rate of 128 Mbps. Furthermore, it should be mentioned that since these interfaces are only used for developmental tasks, both are powered from the USB port, so they do not affect the platform power consumption. Moreover, FTDI, the manufacturer of these two chips, provides drivers and application programming interfaces (APIs) for handling them both from Linux and Windows OS. Apart from these two specific interfaces, the MIGOU platform has two 24-pin expansion connectors with general-purpose inputs/outputs (GPIO), UART, SPI, and 12C interfaces, and it also includes a temperature sensor (Texas Instruments AT30 TS75A) and an accelerometer (NXP MMA8652 FC) on the board itself. The platform can be powered from the two mentioned USB ports by using a power adapter or a single cell Li-ion battery. In addition, MIGOU includes the Texas Instruments BQ27441 fuel gauge to monitor battery parameters, such as the remaining capacity, state-of-charge, voltage, or state-of-health. The management of the different power sources and the battery charge is done through the BQ24166 power management integrated circuit (PMIC) by Texas Instruments. This device provides a stable output voltage of 4.2 V, which in turn is used as the input of the DC-DC converters that generate the necessary voltages for the platform. Specifically, two Texas Instruments TPS62097 converters are used to generate the lower voltages of 1.2 V and 1.8 V, and two Texas Instruments TPS62150A-Q1 converters generate 2.5 V and 3.3 V. All these converters were selected for their high efficiency and the small number of external components they require. The platform includes a selector of the supply voltage of the transceiver (V\({}_{\text{TRX}}\) SEL), so its performance and power consumption can be evaluated at different voltage levels. Since one of the purposes of the platform is to evaluate the energy efficiency of new methods and solutions, MIGOU includes the STMicroelectronics STM32L496 RGT6, an auxiliary MCU (AUX MCU) exclusively dedicated to monitor its current consumption. Specifically, as shown in Figure 1, it monitors the power supply line of the entire system, V\({}_{\text{SUP}}\), and that corresponding to the radio, V\({}_{\text{TRX}}\). For each line, the MCU switches a pair of sensing resistors, which allows it to measure in a range from 1 uA to 100 mA with V\({}_{\text{TRX}}\) and from 300 uA to 300 mA with V\({}_{\text{SUP}}\). With these two monitoring points, the total consumption of the platform and the partial consumptions corresponding to each of the two main parts, the frontend and the backend, can be known. In order to not alter these measurements, the auxiliary MCU has an independent power supply. The current consumption measurements can be  
Figure 3: Active subsystems of the MIGOU platform in I/Q mode (**a**) and BB mode (**b**). sent to an external computer through a USB port, or they can be stored in a MicroSD memory card, which allows for remote monitoring over long periods of time. Figure 4 shows the MIGOU platform and the physical location of its main parts. The printed circuit board (PCB) has four layers and its size is \(148\times 86\) mm. The platform schematics, bill of materials, and manufacturing files are open access and available online (see the Supplementary Materials at the end of this document). Finally, at a software level, the MIGOU platform implements YetiOS [17], an OS that speeds up the development of applications and tests. YetiOS is built on top of FreeRTOS [33] and provides several extra features, such as standard input-output (STDIO), a command shell, and GPIO. It also has advanced memory, timing, and process management modules; Linux-like device drivers; and an adaptive core that allows the OS to improve its performance in dynamic environments.