Mitsubishi Electric Corporation

Mitsubishi Electric Tokki Systems Corporation

Yuichi Nishino

Shumpei Kameyama

Masaharu Imaki

Nobuki Kotake

Hideaki Ochimizu

Hidenobu Tsuji

Takashi Saito

The laser radar device includes: a modulated light generator configured to generate modulated laser light using frequency modulation based on a control parameter; an optical combiner configured to combine the received light and the local light to generate interference light; a photodetector configured to detect the interference light and output an electrical signal; a frequency-to-voltage converter configured to convert the electrical signal into a voltage signal; a characteristic calculator configured to measure a characteristic value of the voltage signal; an evaluator configured to evaluate, on a basis of the characteristic value, whether a center frequency of a spectrum of a return signal component is within a range of a demodulation band of a demodulation circuit; and a parameter setting unit configured to change the control parameter when it is evaluated that the center frequency is not within the range of the demodulation band.

Laser radar device and method for controlling frequency modulation

A system controllerdetermines whether the quality of either a distance image or a light intensity image satisfies reference quality, and, when the quality of either the distance image or the light intensity image dos not satisfy the reference quality, outputs a speed change command to lower a speed, an altitude change command to change a submarine altitude (depth), or the like to a navigation control unit, thereby changing a physical relative relation between a measurement planeand a device in question. As an alternative, the system controller changes a beam scanning rate f, a beam divergence &#x3b8;, or the like within limits at which the amount of variation in a spatial resolution does not exceed a permissible amount.

Laser radar device and radar image generating method

An S/N calculation circuitto calculate the S/N ratio of a received signal, and an S/N comparison circuitto compare the S/N calculated by the S/N calculation circuitwith a threshold Th are disposed, and a parameter setting circuitcontrols the radiation state of a beam radiated from a transmission optical systemaccording to the result of the comparison performed by the S/N comparison circuit. As a result, even if the state of the propagation environment gets worse, degradation in the communication quality can be prevented and communicative stabilization can be achieved.

Communication device

Growing community of inventors

Tokyo, Japan

Yuichi Nishino