• JSTS:Journal of Semiconductor Technology and Science
• /
• v.16 no.6
• /
• pp.745-753
• /
• 2016

This paper presents a fully synthesizable low power interconnect bus for millimeter-scale wireless sensor nodes. A segmented ring bus topology minimizes the required chip real estate with low input/output pad count for ultra-small form factors. By avoiding the conventional open drain-based solution, the bus can be fully synthesizable. Low power is achieved by obviating a need for local oscillators in member nodes. Also, aggressive power gating allows low-power standby mode with only 53 gates powered on. An integrated wakeup scheme is compatible with a power management unit that has nW standby mode. A 3-module system including the bus is fabricated in a 180 nm process. The entire system consumes 8 nW in standby mode, and the bus achieves 17.5 pJ/bit/chip.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.4A
• /
• pp.365-372
• /
• 2007

In IEEE 802.11b wireless network, stations synchronize themselves to the beacons periodically sent by the access point(AP) when they are running in low power mode. In case of missing beacon due to noise or traffic from neighboring wireless network stations must be awake until they get the next beacon, which causes energy consumption in stations. In this paper, we propose a scheme searching next beacon consuming little energy. The problems of missing beacon in low power mode of IEEE 802.11b wireless interface are described and a new method to reduce energy consumption is proposed. The proposed method is simulated with the network simulator, ns2, and compared with the low power mode of the IEEE 802.11b. The result measured in terms of station's wakeup time shows some enhancement in energy consumption when some errors occur in receiving frames.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.1A
• /
• pp.65-71
• /
• 2006

In IEEE 802.11b wireless network, the access point(AP) sends beacons periodically to manage stations when they are running in low power mode. Stations contend for the transmission medium after they receive a beacon and continuously check its state until it becomes available. Thus the energy consumption of each station increases as the load of wireless network. In this paper, we propose a method to reduce energy consumption controlling virtual bitmap in wireless network with multiple stations. The problems of low power mode in IEEE 802.11b wireless interface are described and a new method to reduce energy consumption is proposed. The proposed method is simulated with the network simulator, ns2, and compared with the low power mode of the IEEE 802.11b. The result measured in terms of station's wakeup time shows some enhancement in energy consumption when multiple stations are communicating through the AP in wireless network.