# US 2013/0154703 A1 · Method and System to Measure and Compensate undue DCO Frequency Peaks at GFSK Ramp Down > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0154703 A1 - Document ID: US20130154703A1 - Status: Published application - Kind: A1 - Application number: 13/326,679 - Filed: 2011-12-15 - Published: 2013-06-20 - Earliest claimed: 2011-12-15 - Assignees: Intel Mobile Communications GmbH - Inventors: Bruno Jechoux; Giuseppe Li Puma - Web page: https://patentgrep.com/patent/US20130154703A1 ## CPC - H04L 27/01: Equalisers {(baseband equalizers at the transmitter end H04L25/03343; in analogue transmission systems H04B3/04, H04B7/005)} - H04L 27/08: Amplitude regulation arrangements - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract One embodiment of the invention relates to a communication system having an amplitude modulation path, a frequency deviation component, a characterization component, a peak cancellation component and a compensation unit. The amplitude modulation path is configured to provide an amplitude modulation signal. The frequency deviation component is configured to generate a frequency deviation signal. The characterization component is configured to generate characterization coefficients according to the amplitude modulation signal and the frequency deviation signal. The peak cancellation component is configured to identify peaks according to the amplitude modulation signal and generate a peak cancellation signal to compensate for peak distortion by the identified peaks. The compensation unit utilizes the characterization coefficients, the amplitude modulation signal and the peak cancellation signal to generate a correction signal that compensates for peak distortions and amplitude modulation to frequency modulation effects. ## Claims ### Claim 1 A communication system comprising: a frequency deviation component configured to generate a frequency deviation signal; a characterization component configured to generate characterization coefficients according to a first signal and the frequency deviation signal; a peak cancellation component configured to identify peaks according to the first signal and generate a peak cancellation signal to compensate for peak distortion by the identified peaks; and a compensation unit configured to utilize the characterization coefficients, the first signal and the peak cancellation signal to generate a correction signal that compensates for the peak distortions and amplitude modulation to frequency modulation effects. ### Claim 2 (depends on 1) The system of claim 1, further comprising a summation component configured to receive the phase modulation signal and the correction signal and to generate a corrected modulation signal there from. ### Claim 3 (depends on 2) The system of claim 2, further comprising a digital phase locked loop circuit comprising a digital controlled oscillator and configured to generate a carrier phase modulation signal from the corrected modulation signal. ### Claim 4 (depends on 3) The system of claim 3, wherein the digital phase locked loop circuit is further configured to provide a divided signal to the frequency deviation component. ### Claim 5 (depends on 1) The system of claim 1, wherein the frequency deviation signal represents an instantaneous frequency deviation of the phase modulation signal. ### Claim 6 (depends on 1) The system of claim 1, wherein the first signal is an amplitude modulation signal and wherein the peak cancellation component is configured to monitor the amplitude modulation signal to identify frequency peaks. ### Claim 7 (depends on 6) The system of claim 6, wherein the peak cancellation component is configured to determine a maximum amplitude value. ### Claim 8 (depends on 7) The system of claim 7, wherein the peak cancellation component is configured to generate polynomial factors having selected orders from the maximum amplitude value. ### Claim 9 (depends on 8) The system of claim 8, wherein the compensation unit is configured to utilize the polynomial factors with the characterization coefficients to generate the correction signal. ### Claim 10 (depends on 9) The system of claim 9, wherein the amplitude modulation signal and the phase modulation signal are of a communication sequence having a first portion and a second portion, wherein the characterization component is configured to develop the characterization coefficients during a first portion of a communication sequence and the compensation unit utilizes the characterization coefficients during a second portion of the communication sequence to generate the correction signal. ### Claim 11 A compensation system comprising: a coefficient generator configured to generate a plurality of coefficients according to a frequency deviation signal; factor units configured to generate a plurality of factors according to a first signal; peak cancellation storage components configured to identify peaks and determine maximum amplitude values from the first signal and to provide the maximum amplitude values as outputs only during the identified peaks; peak cancellation summation components configured to add the outputs of the peak cancellation storage components to the plurality of factors to generate peak compensated factors; mixers configured to multiply the peak compensated factors with the plurality of coefficients to generate mixed factors; and a summation component configured to add the mixed factors to generate a correction signal. ### Claim 12 (depends on 11) The system of claim 11, wherein the plurality of coefficients comprise a second order coefficient and a third order coefficient. ### Claim 13 (depends on 11) The system of claim 11, wherein the coefficient generator is configured to utilize a least squares estimate to generate the plurality of coefficients. ### Claim 14 (depends on 11) The system of claim 11, wherein plurality of factors include a second order factor and a third order factor. ### Claim 15 (depends on 11) The system of claim 11, wherein the maximum amplitude values include squared and cubed maximum amplitude values. ### Claim 16 (depends on 11) The system of claim 11, further comprising a summation component to pre-distort a phase modulation signal with the correction signal and generate a corrected phase modulation signal. ### Claim 17 A method of compensating for peak distortions, the method comprising: receiving a first signal; determining one or more factors from the first signal; storing a portion of the one or more factors as maximum factor values; identifying a start of a peak sequence from the first signal; and generating a peak compensation signal during the peak sequence according to the one or more factors and the maximum factor values. ### Claim 18 (depends on 17) The method of claim 17, further comprising using the peak compensation signal as an intermediate correction signal during the peak sequence. ### Claim 19 (depends on 18) The method of claim 18, further comprising generating one or more characterization coefficients from a frequency deviation signal and generating a correction signal from the intermediate correction signal and the characterization coefficients. ### Claim 20 (depends on 17) The method of claim 17, further comprising generating an intermediate correction signal according to the one or more factors.