Pulse waveform producing method

• US 20060140249A1
• Filed: 12/16/2003
• Published: 06/29/2006
• Est. Priority Date: 02/25/2003
• Status: Active Grant

• Current Assignee: Ryuji Kohno, Yokohama TLO Company Limited
• Original Assignee: Ryuji Kohno, Yokohama TLO Company Limited
• Inventors: Kohno, Ryuji
• Granted Patent: US 8,660,206 B2
• Time in Patent Office: Days
• US Class Current: 375/130
• CPC Class Codes: H04B 1/7172 Pulse shape in general H04L25/03834
• CPC Class Codes: H04B 1/719 Interference-related aspects
• CPC Class Codes: H04B 2001/6912 using chirp

Abstract

The present invention forms, in UWB communications in which a pulse of short duration is transmitted, a transmission signal with a desired frequency characteristic by adjusting the shape of a pulse signal used in data transmissions. As a result, radio interference with other wireless systems in UWB communications is reduced. As aspects for adjusting the pulse signal, the present invention comprises an aspect for generating a pulse signal having a desired frequency characteristic by adjusting the shape of a single pulse itself, an aspect for generating a pulse signal having a desired frequency characteristic by combining a plurality of pulses, and an aspect for finding a combination of pulse signals from the frequency characteristic of an object transmission signal.

Claims

1. A method of generating a pulse waveform that generates a signal with a desired frequency characteristic by adjusting the shape of a time pulse in UWB communications in which a pulse of short duration is transmitted.

2. A method of generating a pulse waveform that generates a time pulse shape that satisfies a desired frequency characteristic by adjusting a parameter on a time axis of a single pulse in UWB communications in which a pulse of short duration is transmitted.

3. The method of generating a pulse waveform according to claim 2, wherein a single pulse is formed by means of a waveform that is expressed by w(t)=cos ω

₀t·

exp(−

2π

·

t²/(α

τ

m)²)and a time pulse shape that satisfies the desired frequency characteristic is generated by adjusting a parameter arm that establishes a pulse duration and/or a peak frequency ω

₀ of a power spectrum.

4. The method of generating a pulse waveform according to claim 2, wherein a single pulse is formed by means of a chirp waveform and a time pulse shape that satisfies the desired frequency characteristic is generated by temporally setting the size of the output of the chirp waveform.

5. A method of generating a pulse waveform that generates a time pulse shape that satisfies a desired frequency characteristic by setting a plurality of single pulses on a time axis.

6. The method of generating a pulse waveform according to claim 5, wherein a time pulse shape that satisfies the desired frequency characteristic is generated by forming a dualcycle signal by setting the same two single pulses on a time axis.

7. The method of generating a pulse waveform according to claim 5, wherein a time pulse shape that satisfies the desired frequency characteristic is generated by superposing a plurality of single pulses of different pulse widths.

8. The method of generating a pulse waveform according to claim 5, wherein a time pulse shape that satisfies the desired frequency characteristic is generated by superposing or synthesizing a plurality of single pulses of different pulse widths and waveforms.

9. The method of generating a pulse waveform according to claim 5, wherein a time pulse shape that satisfies the desired frequency characteristic is generated by generating a plurality of pulses of different orders by using a modified Hermite polynomial.

10. A method of generating a pulse waveform that generates a time pulse shape that satisfies a desired frequency characteristic by expanding the desired frequency characteristic in a frequency region and combining a plurality of time pulses selected from among time pulses that form the component of the expanded frequency region, in UWB communications in which a pulse of short duration is transmitted.

11. A method of generating a pulse waveform that generates a time pulse shape that satisfies a desired frequency characteristic by subjecting a desired frequency characteristic or an approximate frequency characteristic to an inverse Fourier transform and combining a plurality of time waveforms selected from among time waveforms obtained by the inverse Fourier transform, in UWB communications in which a pulse of short duration is transmitted.