Portable telephone set and communication base station switching system

• US 7,248,870 B2
• Filed: 05/04/2005
• Issued: 07/24/2007
• Est. Priority Date: 05/31/2000
• Status: Expired due to Fees

• Current Assignee: Lenovo Innovations Ltd Hong Kong (Lenovo Group Ltd.)
• Original Assignee: NEC Corporation
• Inventors: Tamukai, Kiyoshi
• Primary Examiner(s): Tran; CongVan
• Application Number:
  US11/121,068
• Publication Number:
  US 20050192003A1
• Time in Patent Office: 811 Days
• Field of Search: 455436-440, 455/403, 455/424, 455/525, 370/331, 34235706-35707, 342/357.12
• US Class Current: 455/428
• CPC Class Codes: H04W 36/32 by location or mobility data, e.g. speed data
• CPC Class Codes: H04W 36/322 by location data

Abstract

A received electric field measuring section 11 measures the received electric fields from the communicative base station and the neighbor base stations. A received electric field memory section 12 stores received electric field patterns of the communicative base station and two given neighbor stations measured in the received electric field measuring section whenever the communicative base station for communication for the first time is switched over to one of the neighbor base stations. A received electric field pattern comparing section 13 compares the received electric field patterns of the communicative base station having and the two given neighbor stations and the received electric field patterns stored in the received electric field memory section whenever the received electric fields from the communicative base station been in communication with before and the two given neighbor base stations are measured in the received electric field measuring section. A base station position acquiring and switching means 14 and 15 acquires the position of a neighbor station, which the portable terminal is moving toward, in correspondence to a stored received electric field, which is found in the received electric field pattern comparing section to be identical in pattern with a measured received electric field, and switching the communicative base station over to the pertinent neighbor base station.

Claims

1. A communicative base station switching system of a portable terminal for switching a communicative base station while in motion comprising:

a base station memory section for storing base station position data;

a base station position comparing section for receiving position data from a global positioning system of a mobile body and obtaining and comparing the distances of a plurality of neighbor base stations from the portable terminal by using the received position data as the position data of the portable terminal; and

a base station frequency switching section for switching the communicative base station of the portable terminal to one of the plurality of neighbor base stations based only on which of the plurality of neighbor base stations is closest to the portable terminal according to the result of comparison in the base station position comparing section,

wherein the base station position memory section stores latitude and longitude positions the plurality of neighbor base stations; and

wherein the base station frequency switching section switches the communicative base station of the portable terminal to said one of the plurality of neighbor base stations, without measuring a received power level from any of the plurality of neighbor base stations, thereby reducing a time and burden on the base station frequency switching section.

2. The communicative base station switching system according to claim 1, further comprising a global positioning system section for obtaining latitude and longitude positions of the plurality of neighbor base stations.

3. A communicative base station switching system of a portable terminal for switching a communicative base station while in motion in which base station position data and portable terminal position data are obtained, distances of a plurality of neighbor base stations from the portable terminal are obtained on the basis of the obtained position data, and the communicative base station of the portable terminal is switched to one of the plurality of neighbor base stations based only on which of the plurality of neighbor base station is located closest to the portable terminal,

said communication base station switching system further comprising a global positioning system section for obtaining latitude and longitude positions of the plurality of neighbor base stations, and

wherein the communicative base station of the portable terminal is switched to said one of the plurality of neighbor base stations without measuring a received power level from any of the plurality of neighbor base stations, thereby reducing a time and burden on the base station frequency switching section.

4. A communicative base station switching system of a portable terminal for switching a communicative base station while in motion, the system comprising:

a base station memory section that stores base station position data for a plurality of neighbor base stations;

a base station position comparing section that receives position data from a global positioning system of a mobile body and obtains and compares the distances of the plurality of neighbor base stations from the portable terminal by using the received position data as the position data of the portable terminal; and

a base station frequency switching section that switches the communicative base station of the portable terminal to one of the plurality of neighbor base stations based on which of the plurality of neighbor base stations is closest to the portable terminal according to the result of comparison in the base station position comparing section, without measuring a power level from any of the plurality of neighbor base stations, thereby reducing a time and burden on the base station frequency switching section,

wherein the base station position memory section stores latitude and longitude positions of the plurality of neighbor base stations.

5. The communicative base station switching system according to claim 4, further comprising a global positioning system section that obtains latitude and longitude positions of the plurality of neighbor base stations.