Kudrethaya A Shridhara

Title: Innovations by Kudrethaya A Shridhara

Introduction

Kudrethaya A Shridhara is an accomplished inventor based in Cupertino, CA. He has made significant contributions to the field of satellite navigation technology, holding 2 patents that enhance the performance and efficiency of GPS receivers.

Latest Patents

One of his latest patents is titled "Method and apparatus for self-calibration and adaptive temperature compensation in GPS receivers." This invention provides a method and apparatus to optimally estimate and adaptively compensate for the temperature-induced frequency drift of a crystal oscillator in a navigational signal receiver. A Read-Write memory encodes two tables, one for looking up frequency drift values versus temperature readings and another for valid data confirmation on the first table. The initially empty look-up table is gradually populated with frequency drift values while the receiver computes the frequency drift along with its position. During the initial start of the receiver or re-acquisition of satellite signals, the stored frequency drift value corresponding to the current temperature is used. If no valid frequency drift value is available, the frequency drift value is computed based on the existing frequency drift values in the table. This invention reduces the Time-To-First-Fix (TTFF) of the receiver and enables the receiver to self-calibrate, thus no additional factory calibration would be necessary.

Another notable patent is "System and method for fast initialization of navigational satellite signal receivers." This invention provides a method and apparatus for a satellite navigation receiver to lock onto satellite signals in the cold start mode with no information on the receiver position, the satellite position, or time estimates stored in the receiver's memory. All satellites in a positioning system are divided into groups based on the satellite constellation structure. In an embodiment, the positioning system is the Global Positioning System (GPS) and all GPS satellites are divided into three groups. During initialization of the receiver, the satellites are searched per group to lock onto at least one satellite signal. Other satellites are then searched in a given order based on their respective distance or proximity to the first satellite acquired. This method reduces the Time-to-First-Fix (TTFF) ordinarily required by conventional receivers in the cold start mode.

Career Highlights

Kudrethaya has worked with notable companies such as SiRF Technology Holdings, Inc. and SiRF Technology, Inc. His experience in these organizations has contributed to his expertise in satellite navigation technologies.