The Ultra Low-PowerWiseNET System

Abstract

The WiseNET system includes an ultra low-power system-on-chip (SoC) hardware platform and WiseMAC, a low power medium access control protocol (MAC) dedicated to duty-cycled radios. Both elements have been designed to meet the specific requirements of wireless sensor networks and are particularly well suited to ad-hoc and hybrid networks. The WiseNET radio offers dual-band operation (434-MHz and 868-MHz) and runs from a single 1.5-V battery. It consumes only 2.5-mW in receive mode with a sensitivity smaller than −108-dBm at a BER of 10 −3 and for a 100-kb/s data rate. In addition to this low-power radio, the WiseNET system-on-chip (SoC) also includes all the functions required for data acquisition, processing and storage of the information provided by the sensors. Ultra-low power consumption with the WiseNET system is achieved thanks to the combination of the low power consumption of the transceiver and the high energy efficiency of the WiseMAC protocol. The WiseNET solution consumes more than 250 times less power than comparable solutions based on the IEEE 802.15.4 standard.

A Low Power Impulse Radio Design for Body-Area-Networks

“…The CW transmitter sends smaller signal amplitude to save power while the IR sends the same instantaneous power for a shorter duration, saving power by duty cycling. The impulse radio with its inherent duty-cycling at both the receiver and the transmitter will consume power that is reduced by a factor of (20) For the CW radio at various data rates, one can use the (15) and (17) to give the optimized power for the receiver and the transmitter by scaling " " the noise bandwidth due to reduced data rate, as a factor . This allows a smaller signal to be transmitted at the same BER.…”

“…This allows a smaller signal to be transmitted at the same BER. The receiver power ( ), the transmitter power ( ) and the total power ( ) can be given as below (21) Thus, the ratio of the to can be given utilizing (20) and (21) as below, after simplification (i.e., after canceling the term from both the numerator and denominator) (22) As can be seen from (22) for low data rate applications (i.e., ), the impulse radio with its duty-cycled receiver and transmitter will facilitate lower power consumption for a link of given path loss. The same analysis can be done even including the overhead and leakage power, in which the equation for the relative ratio will change to (23) (23) Again, it can be easily seen that the continuous wave radio consumes higher power than the impulse radio, as .…”

“…While there have been efforts to design low power low data rate radios with traditional narrowband architecture, the best radio design in such space still consumes mW of power [18]. At the same time there have been some duty-cycled transceiver-architectures demonstrated to be low power, making them suitable for some of the sensing applications [19], [20]. Impulse radio as an extreme case of these duty-cycled architectures is expected to facilitate ultra low power communication, since the power hungry RF-block need only be on during transmission and reception of short-duration pulses.…”

Wireless microsystems for biomedical applications

“…These control signals combined with optimized control protocols can result in true green networks, where the minimization of power consumptions is a major concern. According to those claimed, their RF transceiver presents a power consumption of either 2.5 mW or 39 mW, when either the receiver or the transmit operation mode is respectively selected [50].…”

Design and performance evaluation of a composite-based back end system for WSNs

“…In this project, we deployed many wireless sensor networks in different areas: Lake Leman, Brest, Thau Lagoon and Ebro River. Each network is composed of CSEM senor nodes [28] implementing wiseMAC [29] and wiseNET [30] protocols. Each node is connected to one/many physico-chemical sensor via an RS485 interface.…”