US 6,982,634 B2
Method and apparatus for reducing blind spots in obstacle detection
Shih-Hsiung Li, 7F-5, No. 23, Sec. 1, Hangchow S. Rd., Taipei (Taiwan)
Filed on Nov. 07, 2002, as Appl. No. 10/289,363.
Prior Publication US 2004/0090316 A1, May 13, 2004
Int. Cl. B60Q 1/00 (2006.01)
U.S. Cl. 340—435 14 Claims
OG exemplary drawing
 
1. A method for reducing blind spots in obstacle detection as a vehicle moves in reverse comprising the steps of:
setting up of two transducers with a wide transmission angle at the rear of the vehicle; and
adoption of channel switching means to allow only one transducer to be in a transmission mode and one transducer to be in a reception mode, while ignoring all ringing signals remaining in a predetermined time frame to prevent cross talk of signals and false triggering of an alarm;
wherein the predetermined time (t) is equal to the closest distance between the two transducers divided by a transmission speed of ultrasonic signals in the air.