TIMING SYNCHRONIZATION METHODS AND APPARATUS
First Claim
1. A method of operating a first mobile communications device operating in an unlicensed frequency band, the method comprising:
- while operating in a first mode of operation, receiving a timing signal of a first type from a second mobile communications device, said first type of timing signal being synchronized to a global timing signal source;
synchronizing an internal clock based on the received timing signal from the second mobile communications device; and
after synchronizing the internal clock, switching to a second mode of operation wherein sleep state intervals in said second mode of operation are longer in duration than sleep state intervals in said first mode of operation.
1 Assignment
0 Petitions
Accused Products
Abstract
Various methods and apparatus are directed to achieving timing synchronization and propagating timing information pertaining to an external, e.g., non Wi-Fi, timing signal source. In some embodiments, a mobile communications device receives and processes a timing signal, e.g., a first Wi-Fi beacon, which is propagating timing information about an external timing signal from a device which directly received the external timing signal. Thus, a mobile wireless communications device achieves timing synchronization with respect to an external timing signal which it is unable to receive directly. In various embodiments, the mobile communications device may, and sometimes does, further propagate the timing information about the external timing signal, e.g., via a second Wi-Fi beacon signal which it generates and transmits. Synchronization with respect to an external signal source facilitates longer sleep states and decreased power consumption.
-
Citations
20 Claims
-
1. A method of operating a first mobile communications device operating in an unlicensed frequency band, the method comprising:
-
while operating in a first mode of operation, receiving a timing signal of a first type from a second mobile communications device, said first type of timing signal being synchronized to a global timing signal source; synchronizing an internal clock based on the received timing signal from the second mobile communications device; and after synchronizing the internal clock, switching to a second mode of operation wherein sleep state intervals in said second mode of operation are longer in duration than sleep state intervals in said first mode of operation. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A first mobile communications device comprising:
-
means for receiving a timing signal of a first type from a second mobile communications device while operating in a first mode of operation, said first type of timing signal being synchronized to a global timing signal source; means for synchronizing an internal clock based on the received timing signal from the second mobile communications device; and means for switching to a second mode of operation, wherein sleep state intervals in said second mode of operation are longer in duration than sleep state intervals in said first mode of operation, after synchronizing the internal clock. - View Dependent Claims (8, 9, 10, 11, 12)
-
-
13. A computer program product for use in a first mobile communications device, the computer program product comprising:
a computer readable medium comprising; code for causing at least one computer to receive a timing signal of a first type from a second mobile communications device while operating in a first mode of operation, said first type of timing signal being synchronized to a global timing signal source; code for causing said at least one computer to synchronize an internal clock based on the received timing signal from the second mobile communications device; and code for causing said at least one computer to switch to a second mode of operation wherein sleep state intervals in said second mode of operation are longer in duration than sleep state intervals in said first mode of operation, after synchronizing the internal clock. - View Dependent Claims (14, 15)
-
16. A first mobile communications device comprising:
-
at least one processor configured to; receive a timing signal of a first type from a second mobile communications device while operating in a first mode of operation, said first type of timing signal being synchronized to a global timing signal source; synchronize an internal clock based on the received timing signal from the second mobile communications device; and switch to a second mode of operation wherein sleep state intervals in said second mode of operation are longer in duration than sleep state intervals in said first mode of operation, after synchronizing the internal clock; and memory coupled to said at least one processor. - View Dependent Claims (17, 18, 19, 20)
-
Specification