Power efficient channel scheduling in a wireless network

Abstract

A method and system for optimizing channel access scheduling for multiple wireless computing devices over a wireless network improves channel access efficiency with respect to a primary channel. An access point, or host computer, includes a host transceiver for receiving control information from the wireless computing devices over a low power channel. Upon receiving the control information, the access point applies a scheduling algorithm to schedule channel access for the wireless computing devices to transmit data over the primary communication channel. The wireless computing devices include a low power radio for receiving scheduling information via the low power channel during idle periods. When the scheduling information is received, the wireless computing device activates its primary channel network interface components to communicate data through the primary channel. When the computing device is idle, the device is configured to power down all of its components with the exception of the circuitry required to power the low power channel. As such, the low power channel is maintained in an active state for receiving scheduling information, such as an access schedule, during both idle and non-idle periods.

1 . A hand-held device for acting as a first node on a wireless network comprising: 
 a high power radio component that communicates data on a primary wireless channel, wherein the data omits scheduling information related to scheduling access to the primary wireless channel; and    a low power radio component that communicates scheduling information related to scheduling access to the primary wireless channel to a second node on the wireless network.    
   
   
       2 . The device according to  claim 1  wherein the scheduling information is derived based at least in part on information selected from the group consisting of a number of packets waiting in a queue for transmission over the primary channel, packet priority information, and data packet transmission deadline information.  
   
   
       3 . The method according to  claim 1  wherein the secondary channel is a low frequency channel having a carrier frequency less than that of the primary channel.  
   
   
       4 . The method according to  claim 1  wherein the primary channel comprises an 802.11 based communication channel.  
   
   
       5 . A network interface card comprising: 
 an first interface to a first wireless channel; and    a second interface to a second wireless channel.    
   
   
       6 . The network interface card according to  claim 5 , wherein the first interface consumes more power to transmit a bit over the first channel than the second interface consumes to transmit a bit over the second channel.  
   
   
       7 . The network interface card according to  claim 6 , wherein the first channel has a carrier frequency that differs from a carrier frequency of the second channel.  
   
   
       8 . An operating system embodied in a computer-readable medium in the form of computer-readable instructions for performing a method comprising: 
 interfacing a host handheld device to a first network for transmitting and receiving data over the first wireless network; and    interfacing the host handheld device to a second network for transmitting and receiving scheduling information over the second wireless network, wherein the scheduling information comprises information usable to schedule access of the host handheld device to the first wireless network.    
   
   
       9 . The operating system according to  claim 8 , wherein the first wireless network uses a higher power wireless signal than the wireless signal used by the second wireless network.