Velocity responsive filtering for pilot signal reception
AssigneeQUALCOMM Incorporated
InventorsGilbert Christopher Sih, Andrew Kan, Stein A. Lundby, Shimman Patel
Life of this patent
Estimating the term…
Abstract
The velocity of a wireless communications device (106) is estimated. In response to this estimate, a filter bandwidth, such as a pilot filter (310) bandwidth, is adjusted so that the introduction of noise and distortion to a signal received by the device is mitigated. The filter bandwidth is adjusted by increasing it as the estimated velocity increases; and decreasing it as the estimated velocity decreases. Such adjustments may be accomplished through providing a number of predetermined bandwidths that each correspond to a particular velocity range, and setting the filter bandwidth to the predetermined bandwidth that corresponds to the estimated velocity.
Claims13
A method of improving the reception of a signal in a wireless communications device (WCD), comprising the steps of:
- (a) estimating the velocity of the WCD based on a level crossing rate, determined based on complete traversal of a hysteresis range bounded by an upper threshold and a lower threshold;
- and
- (b) adjusting a filter bandwidth in the WCD in response to the estimated velocity, to mitigate the introduction of noise and distortion to the signal.
A system for improving the reception of a signal in a wireless communications device (WCD), comprising:
- a velocity estimator that generates a velocity estimate based on a level crossing rate determined based on complete traversal of a hysteresis range bounded by an upper threshold and a lower threshold;
- and
- a filter having a bandwidth that is adjusted in response to velocity estimate, to mitigate the introduction of noise and distortion to the signal.
Dependencies are inferred from the claim text.