Wireless Ad Hoc and Sensor Networks

Distributed Power Control and Rate Adaptation 285ADF7020UHFtranceiverData busControlbusC8051F1208051microprocessorUARTMaxStream XBeeZigbee TM radioFIGURE 6.26Hardware block diagram.at the MAC or Baseband level whereas the latter is great for implementinghigh-level routing and scheduling protocols. Using either the ADF7020 orthe Zigbee radio interface, wireless networks can be formed, and variousnetworking protocols can be implemented for evaluation. A block diagramof the hardware setup is shown in Figure 6.26.6.11.1.2 Generation-4 Smart Sensor NodeThe G4-SSN was originally developed at UMR and subsequently updatedat the St. Louis University. The G4-SSN has various abilities in sensingand processing. The former include strain gauges, accelerometers, thermocouples,and general A/D sensing. The latter include analog filtering,CF memory interfacing, and 8-bit data processing at a maximum of100 MIPS. These features provide a solid application level variability andhave been utilized in previous works (Fonda et al. 2006). Moreover, thestackable connection easily allows for new hardware development. Asseen in Figure 6.27, the Zigbee radio and ADF7020 radio stack can be usedtogether, therefore allowing multiple radio interfaces.As shown in Table 6.4, the G4-SSN provides powerful 8-bit processing,a suitable amount of RAM, and a low-power small form-factor.FIGURE 6.27Gen-4 SSN with Zigbee layer (left), ADF7020 Layer (right).