公开(公告)号：CA2486373A1

公开(公告)日：2003-12-04

申请号：CA2486373

申请日：2003-03-28

Applicant: IBM

Inventor： DOLIVO FRANCOIS ,  DYKEMAN DOUGLAS ,  BINDING CARL ,  HILD STEFAN G ,  KARJOTH GUENTER ,  RUETSCHE ERICH

IPC: G06F17/30 ,  G01S5/02 ,  H04B1/16 ,  H04L12/28 ,  H04W24/00 ,  H04W28/18 ,  H04W64/00 ,  H04Q7/38

Abstract: Methods and devices for determining a geographic location of an electronic device are introduced. A range of radio frequencies at the electronic device ~s location is scanned by a radio receiver (11). Characteristics (CH) of a geographically bound transmission system (3) within said scanned frequencies are identified by a control unit (21). A matching unit (5) matches these characteristics (CH) with stored characteristics (SCH) of geographically bou nd transmission systems of different geographical areas. The geographic locatio n (LD) of said electronic device (1) is dependent on a result of said matching process.

公开(公告)号：CA2059922A1

公开(公告)日：1992-09-28

申请号：CA2059922

申请日：1992-01-23

Applicant: IBM

Inventor： DOLIVO FRANCOIS ,  SCHOTT WOLFGANG

IPC: H04L7/00 ,  G11B20/10 ,  H03M13/00 ,  H04L7/02 ,  H04L7/04 ,  H04L7/10 ,  H04L25/497 ,  G06F13/42

Abstract: SZ 9-90-004 This invention covers a method for fast and reliably detecting the reception of preambles in recording and communication systems using partial-response signaling. Each preamble, transmitted preceding user data, consists of a timing sequence followed by a known sequence of bits marking its end. The invention provides a method for fast and reliably recognizing that synchronization has been achieved and the timing sequence is being received, and detecting the end of the preamble. A hardware implementation based on the inventive method is also described.