High definition timing synchronisation function

Abstract

A high definition timing synchronization function is described. In an embodiment, a wireless station generates a time stamp at a higher resolution than can be broadcast within a standard time stamp field in a frame. The generated time stamp is divided into two parts: the first part being included within the time stamp field and the second part being included within a vendor specific field in the same frame. The frame is transmitted by the wireless station and received by other wireless stations in the wireless network. If the receiving wireless station has the capability, it decodes both the time stamp field and the vendor specific field and recreates the higher resolution time stamp. This higher resolution time stamp is then used to synchronize the receiving wireless station and the transmitting wireless station by resetting a clock or by storing time stamps and corresponding clock values.

What is claimed is: 
     
         1 . A wireless station comprising:
 a clock;   a time stamp generation module arranged to generate a time stamp using the clock and to divide the generated time stamp into two parts, the first part comprising a time stamp at a lower resolution than the generated time stamp and the second part comprising one or more remaining bits of the generated time stamp;   a frame generator module arranged to insert the two parts into different fields within a single frame or within two separate frames; and   a wireless transmitter arranged to transmit the one or two frames comprising the fields containing the parts of the generated time stamp.   
     
     
         2 . The wireless station according to  claim 1 , wherein the frame generator module is arranged to insert the first part into a first field within a frame and the second part into a second field within the same frame. 
     
     
         3 . The wireless station according to  claim 1 , wherein the first part comprises a plurality of most significant bits from the generated time stamp. 
     
     
         4 . The wireless station according to  claim 3 , wherein the first part comprises the 64 most significant bits from the generated time stamp. 
     
     
         5 . The wireless station according to  claim 1 , further comprising:
 an adjustment module arranged to receive one or more error values from other wireless stations, each error value indicating a difference between a received time stamp and a clock value at the other wireless station when the time stamp was received, to compare the received error values to an error target and in response to determining that the error target has been exceeded, to increase a resolution of the generated time stamp.   
     
     
         6 . The wireless station according to  claim 1 , further comprising:
 an adjustment module arranged to receive one or more error values from other wireless stations, each error value indicating a difference between a received time stamp and a clock value at the other wireless station when the time stamp was received, to compare the received error values to an error target and in response to determining that the error target has been exceeded, to increase a number of bits in the second part.   
     
     
         7 . The wireless station according to  claim 1 , further comprising:
 an adjustment module arranged to receive one or more error values from other wireless stations, each error value indicating a difference between a received time stamp and a clock value at the other wireless station when the time stamp was received, to compare the received error values to an error target and in response to determining that the error target has been exceeded, to increase a frequency of transmission of frames comprising the fields containing the parts of the generated time stamp.   
     
     
         8 . The wireless station according to  claim 1 , wherein at least one of the one or two frames is a beacon frame. 
     
     
         9 . The wireless station according to  claim 1 , wherein the wireless station is an access point. 
     
     
         10 . The wireless station according to  claim 1 , wherein the wireless station is a Wi-Fi™ station. 
     
     
         11 . A non-transitory computer readable storage medium having stored thereon computer readable program code, which when processed by an integrated circuit manufacturing system causes the system to generate a processor comprising:
 a time stamp generation module arranged to generate a time stamp using a clock and to divide the generated time stamp into two parts, the first part comprising a time stamp at a lower resolution than the generated time stamp and the second part comprising one or more remaining bits of the generated time stamp; and   a frame generator module arranged to insert the two parts into different fields within a single frame or within two separate frames.   
     
     
         12 . The non-transitory computer readable storage medium according to  claim 11 , wherein the frame generator module is arranged to insert the first part into a first field within a frame and the second part into a second field within the same frame. 
     
     
         13 . The non-transitory computer readable storage medium according to  claim 12 , wherein the first part comprises a plurality of most significant bits from the generated time stamp. 
     
     
         14 . The non-transitory computer readable storage medium according to  claim 13 , wherein the first part comprises the 64 most significant bits from the generated time stamp. 
     
     
         15 . The non-transitory computer readable storage medium according to  claim 11 , wherein the processor further comprises one of:
 a first adjustment module arranged to receive one or more error values from other wireless stations, each error value indicating a difference between a received time stamp and a clock value at the other wireless station when the time stamp was received, to compare the received error values to an error target and in response to determining that the error target has been exceeded, to increase a resolution of the generated time stamp;   a second adjustment module arranged to receive one or more error values from other wireless stations, each error value indicating a difference between a received time stamp and a clock value at the other wireless station when the time stamp was received, to compare the received error values to an error target and in response to determining that the error target has been exceeded, to increase a number of bits in the second part; and   a third adjustment module arranged to receive one or more error values from other wireless stations, each error value indicating a difference between a received time stamp and a clock value at the other wireless station when the time stamp was received, to compare the received error values to an error target and in response to determining that the error target has been exceeded, to increase a frequency of transmission of frames comprising the time stamp field and the vendor specific field.   
     
     
         16 . A method of operation of a wireless station, the method comprising:
 generating a time stamp;   dividing the generated time stamp into two parts, the first part comprising a time stamp at a lower resolution than the generated time stamp and the second part comprising one or more remaining bits of the generated time stamp;   inserting the two parts into different fields within a single frame or within two separate frames; and   transmitting the one or two frames comprising the fields containing the parts of the generated time stamp.   
     
     
         17 . The method according to  claim 16 , wherein the first part is inserted into a first field within a frame and the second part into a second field within the same frame. 
     
     
         18 . The method according to  claim 16 , wherein at least one of the one or two frames is a beacon frame. 
     
     
         19 . The method according to  claim 16 , wherein the first part comprises a plurality of most significant bits from the generated time stamp. 
     
     
         20 . The method according to  claim 16 , wherein the second part comprises all the remaining bits of the generated time stamp.