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. 08, 2019
Filed:
Aug. 19, 2016
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Hiroshi Yamazaki, Atsugi, JP;
Munehiko Nagatani, Atsugi, JP;
Hideyuki Nosaka, Atsugi, JP;
Akihide Sano, Yokosuka, JP;
Yutaka Miyamoto, Yokosuka, JP;
NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo, JP;
Abstract
In the conventional technique, only an output having a bandwidth identical to the bandwidth of individual DACs has been obtained even by using a plurality of DACs. Also, even when the output of a bandwidth broader than the individual DAC is obtained, there has been a problem associated with asymmetricity of a circuit configuration. In a signal generating device of the present invention, a plurality of normal DACs are combined to realize an analog output of a broader bandwidth beyond the output bandwidth of the individual DACs, and the problem of the asymmetricity of the circuit configuration is also resolved. A desired signal is separated into a low-frequency signal and a high-frequency signal in a frequency domain, and a series of operation of constant (r)-folding the amplitude of the high-frequency signal and shifting it on the frequency axis to superimpose it on the low-frequency signal are made in a digital domain. The output of each DAC is switched by an analog multiplexer.