Mitsubishi Denki Kabushiki Kaisha

Takehiro Inoue

Yuji Yokoi

A digital synthesizer is provided with an address converter means for converting a phase value in the region of small amplitude change all to a predetermined value, utilizing the characteristics of a sinusoidal function. In addition, a digital synthesizer is provided with a second address converter for converting the phase value in a range of 0.degree..about.360.degree. to a phase value of 0.degree..about.90.degree. and an output data inverter inverting the memory output in response to the phase value. By converting a phase value in the region of a small amplitude change to a predetermined value, the amplitude value to be stored in the memory can be reduced by that degree, and reduction in the memory capacity and reduction in the power dissipation are achieved. Furthermore, by converting the phase value in a range of 0.degree..about.360.degree. to a phase value of 0.degree..about.90.degree. utilizing symmetry of the sinusoidal function, the amplitude value to be stored in the memory can be reduced to one-fourth, thereby further reduction in the memory capacity and further reduction in the power dissipation are achieved.

Digital wave synthesizer with address conversion for reducing memory

A cordless telephone system serves a building with a moving conveyance such as an elevator. The system has at least one portable cordless telephone, at least one fixed base station that communicates with the portable cordless telephone by a wireless circuit outside the moving conveyance, and a moving-conveyance base station that communicates with the portable cordless telephone by a wireless circuit inside the moving conveyance. A central switch routes calls to the fixed base station or moving-conveyance base station according to the field strength of signals received at these stations from the portable cordless telephone.

Growing community of inventors

Amagasaki, Japan

Takehiro Inoue