Ross E Bland

US Patent:

8078130, Dec 13, 2011

Filed:

Dec 23, 2008

Appl. No.:

12/317486

Inventors:

Gerald L. Fudge - Rockwall TX, US
Ross E. Bland - Dallas TX, US
Antone L. Kusmanoff - Greenville TX, US

Assignee:

L-3 Communications Integrated Systems L.P. - Greenville TX

International Classification:

H04B 1/10

US Classification:

455295, 455296, 455307

Abstract:

Systems and methods for interference cancellation in which a first signal having a first frequency may be cancelled with a second frequency having a second and different (e. g. , lower) frequency by employing sampling to cancel the first signal with the separate signal at the sample instances.

US Patent:

8509354, Aug 13, 2013

Filed:

Dec 2, 2009

Appl. No.:

12/592777

Inventors:

Gerald L. Fudge - Rockwall TX, US
Ross E. Bland - Dallas TX, US
Sujit Ravindran - Dallas TX, US
Mark A. Chivers - McKinney TX, US

Assignee:

L—3 Communications Integrated Systems L.P. - Greenville TX

International Classification:

H04L 27/00

US Classification:

375324, 375130, 375147, 375316

Abstract:

Improved spur reduction architectures that improve linearity in direct radio frequency (RF) receiver architectures. Non-uniform sampling in the form of sampling clock phase (or frequency) modulation is used to induce phase (or frequency) modulation on signals that are being received from a given Nyquist zone. At the output of the ADC (analog-to-digital converter), the signals are de-modulated to remove the induced modulation based on the Nyquist zone that is being received. The de-modulation process results in non-desired spurious artifacts (interfering leakage signals and ADC spurs) being spread in the frequency domain. Strong spurious artifacts may be removed after measuring the induced modulation and de-modulating. For the case of weak spurious artifacts, the de-modulation for the desired Nyquist zone spread these signals in the frequency domain. Induced modulation on signals may also provide a dithering effect on the ADC.