Method and apparatus for acquiring low duty-cycle reference signals in a mobile communications environment
First Claim
1. A method whereby a communications terminal can acquire a low duty-cycle reference signal over a large frequency range, comprising the steps of:
- receiving a plurality of reference signal frequencies;
sampling said plurality of reference signal frequencies for a first predetermined period of time, said first predetermined period of time associated with a size of a memory device in said communications terminal;
processing, off-line, said sampling of said plurality of reference signal frequencies for a second predetermined period of time, said second predetermined period of time associated with an analysis time; and
selecting the first and second predetermined periods of time to avoid missing successive reference beacons within the received reference signal frequencies used to acquire the low duty-cycle reference signal.
4 Assignments
0 Petitions
Accused Products
Abstract
A method is provided whereby a mobile cellular terminal can acquire and lock onto a low duty-cycle reference beacon transmitted from a private radio system base station. The terminal alternately scans the private radio beacon frequency spectrum (over a large frequency range) and processes the received signals off-line until the reference beacon is found. During each scan, only a limited amount of sampling time is allowed, in order to keep the amount of sampled data manageable. The processing time is selected so as to be long enough for the terminal to complete any required (software) analysis of the sampled data. Consequently, even if the terminal misses a reference beacon that arrives during the processing period, the next consecutive reference beacon will be found.
-
Citations
25 Claims
-
1. A method whereby a communications terminal can acquire a low duty-cycle reference signal over a large frequency range, comprising the steps of:
-
receiving a plurality of reference signal frequencies; sampling said plurality of reference signal frequencies for a first predetermined period of time, said first predetermined period of time associated with a size of a memory device in said communications terminal; processing, off-line, said sampling of said plurality of reference signal frequencies for a second predetermined period of time, said second predetermined period of time associated with an analysis time; and selecting the first and second predetermined periods of time to avoid missing successive reference beacons within the received reference signal frequencies used to acquire the low duty-cycle reference signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A method for use by a mobile communications terminal to acquire a low duty-cycle reference signal having a period, P, comprising the steps of:
-
scanning a band of reference signal frequencies for a first predetermined period of time, N1; processing for a second predetermined period of time, N2, information obtained during said first predetermined period of time; and repeating each of said scanning and processing steps K times during said period P, whereby two conditions are fulfilled simultaneously;
space="preserve" listing-type="equation">K*N1+(K-1)*N2≧
P+1; and
space="preserve" listing-type="equation">K*N2+(K-1)*N1≦
P-1. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
-
-
25. A GSM mobile communications terminal for use in acquiring a low duty-cycle reference signal having a period, P, said low duty-cycle reference signal is transmitted from a private radio system base station, said GSM mobile communications terminal comprising:
-
scanning means for scanning a band of reference signal frequencies for a first predetermined period of time, N1; and processing means for processing for a second predetermined period of time, N2, information obtained during said first predetermined period of time, said scanning means and said processing means are actuated K times during said period P so that two conditions are fulfilled simultaneously;
space="preserve" listing-type="equation">K*N1+(K-1)*N2≧
P+1; and
space="preserve" listing-type="equation">K*N2+(K-1)*N1≦
P-1.
-
Specification