The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 09, 2007
Filed:
Mar. 29, 2003
David Bruce Isaksen, Mountain View, CA (US);
Mark Fong, San Jose, CA (US);
David Bruce Isaksen, Mountain View, CA (US);
Mark Fong, San Jose, CA (US);
WideBand Semiconductors, Inc., Mountain View, CA (US);
Abstract
An apparatus for modulating a digital input signal having a pre-assigned symbol rate and having a baseband carrier frequency by using a single sample clock signal. The pre-assigned symbol rate is selected from the group consisting of a plurality of symbol rates. The apparatus in a baseband mode comprises: (a) an Interpolate_by_2_Nyquist Filter block configured to double the pre-assigned symbol rate, to perform Nyquist filtering operation, and configured to output an Inphase (I) and a Quadrature (Q) components of the pre-assigned signal having the double symbol rate; (b) a Complex Shaper block configured to pre-compensate the spectrum of I and Q components of the signal having the double symbol rate in advance for a spectrum distortion caused by the apparatus; ©) a Cascaded Integrated Comb (CIC) Interpolator filter configured to increase by an interpolation R factor the sample rate of the signal as compared with a sample rate of the baseband carrier; (d) a Phase Shifter configured to compensate a phase of interpolated by R signal for a known quadrature error; (e) an Inphase (I) channel and Quadrature (Q) channel Gain blocks configured to pre-compensate the I and Q components of the interpolated by R signal for a known gain difference circuit between the I and Q channel gains; (f) an I and Q channel DC offset blocks configured to pre-compensate I and Q components of the interpolated by R signal for a known DC offset difference circuit between I and Q channel DC offset blocks; and (g) a Controller block configured to supply a plurality of control signals to the apparatus. In the passband mode, I and Q channel Gains are set to one, and I and Q channel DC offsets are set to zero.