| US 7,526,257 B2 | ||
| Mobile communication terminal and cell search circuit | ||
| Miyuki Ogura, Tachikawa (Japan) | ||
| Assigned to Kabushiki Kaisha Toshiba, Tokyo (Japan) | ||
| Filed on Mar. 05, 2004, as Appl. No. 10/793,215. | ||
| Claims priority of application No. 2003-172000 (JP), filed on Jun. 17, 2003. | ||
| Prior Publication US 2004/0259503 A1, Dec. 23, 2004 | ||
| Int. Cl. H04B 1/44 (2006.01) | ||
| U.S. Cl. 455—78 [455/67.11; 455/423] | 10 Claims |
| 1. A mobile communication terminal used in a cellular mobile communication system, comprising:
a module configured to measure, at a first interval between successive searches, a reception quality of a radio signal transmitted
from an active base station serving the mobile communication terminal in a standby mode;
a module configured to evaluate the measured reception quality;
a module configured to change the first interval between successive searches to a second interval, different from the first
interval, on the basis of an evaluation result of the reception quality;
a module configured to store the measured reception quality; and
a filtering module configured to execute filtering processing for the measured latest reception quality and a stored past
reception quality on the basis of an evaluation result of the reception quality by the evaluation module and input the reception
qualities that have undergone the filtering processinq to the evaluation module,
wherein the reception quality evaluation module determines whether the measured reception quality is in a satisfactory state
wherein the reception quality is more than a threshold value,
when the measured reception quality has changed from a degraded state wherein the reception quality is less than the threshold
value to the satisfactory state, the interval change module changes the first interval to the second interval longer than
the first interval, and
wherein the evaluation module determines whether the measured reception guality is in a satisfactory state wherein the reception
quality is more than a threshold value, and when the evaluation module evaluates that the reception quality is in the satisfactory
state wherein the reception quality is more than the threshold value, the filtering module selects the measured latest reception
quality and inputs the latest reception quality to the evaluation module, and when the evaluation module evaluates that the
reception quality is in a degraded state wherein the reception guality is less than the threshold value, the filtering module
selects both the measured latest reception quality and the stored past reception quality, calculates a reception quality,
and inputs the calculated reception guality to the evaluation module.
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