Stephen A Henderson

US Patent:

6252867, Jun 26, 2001

Filed:

Sep 30, 1999

Appl. No.:

9/409546

Inventors:

Jeff L. Pfeil - Bartlett IL
Alan P. Rottinghaus - Barrington IL
Stephen W. Henderson - Chicago IL
Javier J. Tapia - Wheaton IL

Assignee:

Motorola, Inc. - Scahumburg IL

International Classification:

H04B 1702
H04B 138
H04B 7216
H04Q 720
H04M 100

US Classification:

370335

Abstract:

An apparatus (100) and method dynamically allocates radio frequency receive path resources as required by a programmable location engine (112). The programmable location engine (112) employs cascaded time of arrival and direction of arrival algorithms to determine per remote unit location data. The apparatus (100) employs a phased array antenna (104) and a programmable receiver switching apparatus (108). A plurality of radio frequency receivers (102a-102n) receive a plurality of different carriers, such as CDMA carriers, on each of a different phased array antenna element (106a-106d). An RF switching matrix (126) and mobile location shared resource controller (110) dynamically switch the plurality of radio frequency receivers (102a-102b) to not only receive the different carriers on each of the different phased antenna radio elements to determine time of arrival information, but alternately receive a same carrier signal over all or a portion of the phased array antenna element to determine direction of arrival information.

US Patent:

62088424, Mar 27, 2001

Filed:

Sep 30, 1999

Appl. No.:

9/409213

Inventors:

Stephen W. Henderson - Chicago IL
Jeff L. Pfeil - Bartlett IL
Javier J. Tapia - Wheaton IL

Assignee:

Motorola Inc. - Schaumburg IL

International Classification:

H04B17/00

US Classification:

455 671

Abstract:

A method and apparatus for estimating mobile radio channel parameters by dynamically determining the delay offset, carrier frequency offset, and coherent averaging length that yields the optimum despreading gain for current channel conditions. Obtaining the optimal despreading gain increases the fidelity of desired channel parameter estimates, (such as delay, phase, and the complex impulse response), and also expands the range of conditions under which they can be feasibly measured. A plurality of delay offsets, carrier frequency offsets, and coherent averaging lengths are considered for each measurement of channel parameters. An energy metric assigned to each combination of delay offset and coherent averaging length, and this value measures the despreading gain for these conditions.