Method for superframe management and coordinator thereof

Abstract

A method and a coordinator of superframe management are disclosed. The method includes receiving, by a coordinator, a GTS request from a node; determining the type of the node; allocating GTS in an active period based on GTS characteristics carried in the GTS request when the node is determined as an energy restricted device; allocating GTS in an active period and an inactive period based on GTS characteristics carried in the GTS request when the node is determined as an energy unrestricted device.

1 . A method of superframe management, comprising:
 receiving, by a coordinator, a Guaranteed Time Slots (GTS) request from a node; determining a type of the node; and   allocating GTS in an active period and an inactive period based on GTS characteristics carried in the GTS request when the node is determined as an energy unrestricted device.   
     
     
         2 . The method of  claim 1 , wherein the GTS characteristics comprise at least the length of the requested GTS. 
     
     
         3 . The method of  claim 2 , wherein after the node is determined as the energy unrestricted device and before the GTS is allocated in the active period and the inactive period, the method further comprises:
 determining whether or not to allocate the GTS in the inactive period based on the GTS characteristics;   allocating the GTS in the active period and the inactive period if it is determined to allocate the GTS in the inactive period; and   allocating the GTS starting from a position in the active period adjacent to the inactive period in the superframe if it is determined not to allocate the GTS in the inactive period.   
     
     
         4 . The method of  claim 2 , wherein allocating the GTS in the active period and in the inactive period comprises:
 allocating a first portion of the GTS to the node in the active period adjacent to the inactive period in the superframe and allocating a second portion of GTS to the node in the inactive period if a remaining length in the current active period is less than the length of requested GTS and the remaining length plus a predetermined length allowable for the node to conduct transmission in the inactive period is longer than or equal to the length of the requested GTS, wherein the sum of the length of the first portion of GTS and the length of the second portion of the GTS equals the length of the requested GTS.   
     
     
         5 . The method of  claim 4 , wherein before allocating the first portion of the GTS in the active period adjacent to the inactive period in the superframe, the method further comprises:
 determining if the active period in the superframe already includes a GTS corresponding to the energy unrestricted device;   allocating the GTS in the active period in the superframe according to a first-come-first-served policy if the active period already includes the GTS corresponding to the energy unrestricted device; and   allocating the first portion of GTS to the node in the active period adjacent to the inactive period in the superframe if the active period in the superframe does not include the GTS corresponding to the energy unrestricted device.   
     
     
         6 . The method of  claim 3 , wherein before allocating the GTS starting from a position adjacent to the inactive period in the superframe, the method further comprises:
 determining if the active period in the superframe already includes a GTS corresponding to the energy unrestricted device;   allocating the GTS according to a first-come-first-served policy if the active period already includes the GTS corresponding to the energy unrestricted device; and   allocating the GTS starting from a position adjacent to the inactive period in the superframe if the active period in the superframe does not include the GTS corresponding to the energy unrestricted device.   
     
     
         7 . The method of  claim 3 , further comprising:
 adjusting the position of the allocated GTS if the active period in the superframe already includes GTS which is allocated to an energy restricted device and which is adjacent to the inactive period, such that the length of the GTS adjacent to the inactive period meets the length of the GTS in the active period required currently by the energy unrestricted device; and   informing, at the same time, by the coordinator, each corresponding node of the adjusted GTS characteristics via a beacon frame in the superframe.   
     
     
         8 . The method of  claim 1 , further comprising:
 pre-storing node parameters in the coordinator; and   wherein the step of determining the type of the node comprises:   searching, by the coordinator according to address information of the node, the node parameters for the type of node which matches the address, wherein the type of node is the current node initiating the GTS request.   
     
     
         9 . The method of  claim 1 , further comprising:
 allocating the GTS in the active period if the node is determined as an energy restricted device.   
     
     
         10 . A coordinator, comprising:
 a receiving module, configured to receive a Guaranteed Time Slots (GTS) request from a node;   a determination module, configured to determine a type of the node; and   an allocation module, configured to allocate GTS in an active period and an inactive period based on GTS characteristics carried in the GTS request received by the receiving module when the determination module determines that the node is an energy unrestricted device.   
     
     
         11 . The coordinator of  claim 10 , wherein the allocation module comprises:
 a first allocation sub-module, configured to allocate GTS to the node in the active period in the superframe adjacent to the inactive period;   a determination sub-module, configured to determine if a remaining length in the active period is shorter than the length of the requested GTS and the remaining length plus a predetermined length allowable for the node to conduct transmission in the inactive period is longer than or equal to the length of the requested GTS; and   a second allocation sub-module, configured to allocate the remaining GTS in the inactive period to the node when the result of the determination sub-module is yes.   
     
     
         12 . The method of  claim 3 , wherein allocating GTS in the active period and in the inactive period comprises:
 allocating a first portion of the GTS to the node in the active period adjacent to the inactive period in the superframe and allocating a second portion of the GTS to the node in the inactive period if a remaining length in the current active period is less than the length of requested GTS and the remaining length plus a predetermined length allowable for the node to conduct transmission in the inactive period is longer than or equal to the length of the requested GTS, wherein the sum of the length of the first portion of the GTS and the length of the second portion of the GTS equals the length of the requested GTS.   
     
     
         13 . The method of  claim 5 , further comprising:
 adjusting the position of the allocated GTS if the active period in the superframe already includes the GTS which is allocated to an energy restricted device and which is adjacent to the inactive period, such that the length of the GTS adjacent to the inactive period meets the length of the GTS in the active period required currently by the energy unrestricted device; and   informing, at the same time, by the coordinator, each corresponding node of the adjusted GTS characteristics via a beacon frame in the superframe.   
     
     
         14 . The method of  claim 6 , further comprising:
 adjusting the position of the allocated GTS if the active period in the superframe already includes the GTS which is allocated to an energy restricted device and which is adjacent to the inactive period, such that the length of the GTS adjacent to the inactive period meets the length of the GTS in the active period required currently by the energy unrestricted device; and   informing, at the same time, by the coordinator, each corresponding node of the adjusted GTS characteristics via a beacon frame in the superframe.