Pulse or digital communications – Systems using alternating or pulsating current – Amplitude modulation
Reexamination Certificate
2007-07-24
2007-07-24
Kim, Kevin (Department: 2611)
Pulse or digital communications
Systems using alternating or pulsating current
Amplitude modulation
C375S278000, C375S285000, C375S300000, C332S103000, C332S144000, C332S145000, C332S149000
Reexamination Certificate
active
10275424
ABSTRACT:
A method for reducing out-of-band emission in an AM transmitter for digital transmission includes generating, from a digital modulation signal, an amplitude signal and a phase-modulated radio frequency signal configured to control the AM transmitter. A digital modulation process is used in which a hole is formed around a 0/0 point so that a zero crossing is avoided by a substantial margin in a vector diagram representation. Thereby a respective bandwidth of the amplitude signal and the phase-modulated radio frequency signal is limited so that the out-of-band emission decreases as a function of a shoulder distance achievable by the AM transmitter at a rate where a spectrum mask is not exceeded.
REFERENCES:
patent: 4403255 (1983-09-01), Schiff
patent: 4955072 (1990-09-01), Tomljenovic
patent: 5646962 (1997-07-01), Harrison
patent: 6125103 (2000-09-01), Bäuml et al.
patent: 6751267 (2004-06-01), Schill et al.
patent: 32 43 489 (1983-06-01), None
patent: 195 35 030 (1996-04-01), None
patent: 44 41 323 (1996-05-01), None
patent: 195 41 441 (1996-06-01), None
patent: 196 35 813 (1998-03-01), None
patent: 19717169 (1998-10-01), None
patent: 198 08 993 (1999-09-01), None
patent: 0 708 546 (1996-04-01), None
patent: 0708545 (1996-04-01), None
patent: 0 874 483 (1998-10-01), None
Jochen H. Schiller, Mobile Communications, 2003, Addison-Wesley, Second Edition, pp. 46-54.
Raab et al., “L-Band Transmitter Using Kahn EER Technique”, IEEE Transactions on Microwave Theory and Techniques, vol. 46, No. 12, Dec. 1998□□.
Namiki, Junji, “An automatically Controlled Predistorter for Multilevel Quadrature Amplitude Modulation”, IEEE Transactions on Communications, vol. COM-31 No. 5 May 1983.
Yamazato et al, “Performance evaluation of modified HPSK for Wideband CDMA”, IEEE 6th Int. Symp. On Spread-Spectrum Tech. And Appli. NJIT, New Jersey, Sep. 6-8, 200.
Recommendation ITU-R SM.328-9: “Spectra and Bandwidth of Emissions”, pp. 1-38, 1948.
International Search Report for International Application No. PCT/EP02/00431 (2 pages), Mar. 3, 2003.
Rudolph Dietmar
Schaefer Andreas
Deutsche Telekom AG
Kim Kevin
Wong Linda
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