Abstract: The present invention relates to a method of scheduling for an underwater wireless mobile network. Particularly, the present invention relates to a method of scheduling for an underwater wireless mobile network, whereby the method may consider a scheduling method that does not cause collision at a specific time domain, and improve network efficiency by receiving in a sink node a packet in a packet train form in consideration with a transfer velocity of a sound wave and a packet length rather than performing orthogonalization to avoid transmission time overlap at a specific time.

Abstract: The present invention relates to a method of scheduling for an underwater wireless mobile network. Particularly, the present invention relates to a method of scheduling for an underwater wireless mobile network, whereby the method may consider a scheduling method that does not cause collision at a specific time domain, and improve network efficiency by receiving in a sink node a packet in a packet train form in consideration with a transfer velocity of a sound wave and a packet length rather than performing orthogonalization to avoid transmission time overlap at a specific time.

Abstract: The present invention relates to a container search system comprising: a radiation irradiation unit for irradiating radiation to a container to be inspected; a detection unit installed opposite to the radiation irradiation unit to detect radiation having passed through a container; a transfer cart for loading an automobile thereon, on which a container to be inspected is loaded, and travelling along a search path formed between the radiation irradiation unit and the detection unit; and a circulation orbit unit formed to allow the transfer cart to circulate along the search path, wherein a primary side of a linear induction motor for generating a moving magnetic field is formed on either side among the transfer cart and the search path and a secondary-side reaction plate for inducing a secondary eddy current due to the moving magnetic field and generating a linear driving force is formed on the other side thereof.

Abstract: A method of automatically assigning IP in a ship ad-hoc network includes (A) receiving a non-duplicate IP block from a terrestrial station by transmitting/receiving an IP request signal and an IP request response signal generated from a data link layer by one-hop ship stations able to perform direct transmission/reception with the terrestrial station; (B) allowing the one-hop ship stations receiving IP blocks to determine IPs thereof and to allocate IP blocks, as IP providers, to multi-hop ship stations able to perform indirect transmission/reception with the terrestrial station through ad-hoc communication when the multi-hop ship stations request the IP blocks; and (C) determining one of the IP providers to transmit an IP request signal such that the determined IP provider transmits an IP request response signal when multi-hop ship stations, to which the IP blocks are not allocated, receive MAC frames of plural IP providers in a channel allocation.

Abstract: The present invention relates to a container search system comprising: a radiation irradiation unit for irradiating radiation to a container to be inspected; a detection unit installed opposite to the radiation irradiation unit to detect radiation having passed through a container; a transfer cart for loading an automobile thereon, on which a container to be inspected is loaded, and travelling along a search path formed between the radiation irradiation unit and the detection unit; and a circulation orbit unit formed to allow the transfer cart to circulate along the search path, wherein a primary side of a linear induction motor for generating a moving magnetic field is formed on either side among the transfer cart and the search path and a secondary-side reaction plate for inducing a secondary eddy current due to the moving magnetic field and generating a linear driving force is formed on the other side thereof.

Abstract: Disclosed is an apparatus and method for estimating a Doppler shift for underwater communication. The apparatus includes: a multipath delay profile determiner for detecting a correlation of a known signal 1 and a received packet signal and time (T1o) at a point having maximum energy of the correlation, and detecting a multipath delay profile at the time (T1o); a correlation calculator for calculating a correlation between a correlation of a known signal 2 and the received packet signal, and the multipath delay profile; a maximum value detector for detecting time (T2o) at a point having maximum energy of the correlation calculated by the correlation calculator; and a Doppler shift estimator for determining a Doppler shift using a difference between the time (T1o) and the time (T2o) at points having respective maximum energy.

Abstract: Provided is an apparatus for equalizing a channel and determining reception data of a packet communication receiver. The apparatus includes: an input interface unit which receives a reception sample string of a packet having a midamble and location information of the midamble; a sample dividing unit which divides the reception sample string into a first sub sample string and a second sub string stream using the location information of the midamble; and a channel equalizing unit which performs channel equalization on the first sub sample string and the second sub sample string, respectively, using a channel equalizing algorithm of the channel equalizer.

Abstract: The present invention relates to the prevention of bus conflicts in the backplane by providing a bus structure which is configured to control the activation of an attached slave board in the backplane to/from which a plurality of slave boards are attached and detached. The backplane according to the present invention can prevent data bus conflicts and improve the stability of a corresponding system by configuring general purpose I/O (GPIO) pins in a 2 bit request/grant scheme between a master board and the plurality of slave boards. Accordingly, the present invention can improve system reliability, maintainability, and competitiveness in various fields such as the fields of communication devices and server devices, remote monitors and control systems, vessel communications, aircraft communications, and wired and wireless communications in which various protocols are combined and implemented.

Abstract: A method of automatically assigning IP in a ship ad-hoc network includes (A) receiving a non-duplicate IP block from a terrestrial station by transmitting/receiving an IP request signal and an IP request response signal generated from a data link layer by one-hop ship stations able to perform direct transmission/reception with the terrestrial station; (B) allowing the one-hop ship stations receiving IP blocks to determine IPs thereof and to allocate IP blocks, as IP providers, to multi-hop ship stations able to perform indirect transmission/reception with the terrestrial station through ad-hoc communication when the multi-hop ship stations request the IP blocks; and (C) determining one of the IP providers to transmit an IP request signal such that the determined IP provider transmits an IP request response signal when multi-hop ship stations, to which the IP blocks are not allocated, receive MAC frames of plural IP providers in a channel allocation.

Abstract: Provided is an apparatus for equalizing a channel and determining reception data of a packet communication receiver. The apparatus includes: an input interface unit which receives a reception sample string of a packet having a midamble and location information of the midamble; a sample dividing unit which divides the reception sample string into a first sub sample string and a second sub string stream using the location information of the midamble; and a channel equalizing unit which performs channel equalization on the first sub sample string and the second sub sample string, respectively, using a channel equalizing algorithm of the channel equalizer.

Abstract: The present invention relates to a driving apparatus for a motor. The driving apparatus for the motor is provided with a rotor position detection unit for detecting position information of a rotor of the motor, a motor driving unit for driving the motor by applying current to the motor, a current detection unit for detecting a current that is applied to the motor, a filter for removing noise included in a signal outputted from the current detection unit and outputting the signal, and a motor control unit for outputting, to the motor driving unit, a motor driving control signal in which the time delay from the filter is recorded and which compensates for the time delay to the signal from the filter. Using the driving apparatus for the motor, the drive of the motor can be controlled so as to compensate for the time delay from the filter using a value that is calculated in advance and memorised, thereby improving driving efficiency.

Abstract: Disclosed is an apparatus and method for estimating a Doppler shift for underwater communication. The apparatus includes: a multipath delay profile determiner for detecting a correlation of a known signal 1 and a received packet signal and time (T10) at a point having maximum energy of the correlation, and detecting a multipath delay profile at the time (T10); a correlation calculator for calculating a correlation between a correlation of a known signal 2 and the received packet signal, and the multipath delay profile; a maximum value detector for detecting time (T20) at a point having maximum energy of the correlation calculated by the correlation calculator; and a Doppler shift estimator for determining a Doppler shift using a difference between the time (T10) and the time (T20) at points having respective maximum energy.

Abstract: The present invention relates to the prevention of bus conflicts in the backplane by providing a bus structure which is configured to control the activation of an attached slave board in the backplane to/from which a plurality of slave boards are attached and detached. The backplane according to the present invention can prevent data bus conflicts and improve the stability of a corresponding system by configuring general purpose I/O (GPIO) pins in a 2 bit request/grant scheme between a master board and the plurality of slave boards. Accordingly, the present invention can improve system reliability, maintainability, and competitiveness in various fields such as the fields of communication devices and server devices, remote monitors and control systems, vessel communications, aircraft communications, and wired and wireless communications in which various protocols are combined and implemented.

Abstract: Apparatus and method of transmitting a preamble having additional information in differential modulation packet data communication. The apparatus includes a phase rotator that outputs a phase rotation quantity corresponding to additional information to be applied to a transmission target packet, a transmission-multiplier that multiplies the phase rotation quantity output from the phase rotator by a preamble to be transmitted, a symbol mapper that converts header and payload data to be applied to the transmission target packet into symbols and outputs the same, a multiplexer that processes an output signal of the transmission-multiplier and an output signal of the symbol mapper to be selectively output through an output end to form a symbol stream in units of packets, and a differential symbol converter that converts the symbol stream output from the multiplexer according to a predetermined differential modulation method and outputs the converted symbol stream.

Abstract: Apparatus and method of transmitting a preamble having additional information in differential modulation packet data communication. The apparatus includes a phase rotator that outputs a phase rotation quantity corresponding to additional information to be applied to a transmission target packet, a transmission-multiplier that multiplies the phase rotation quantity output from the phase rotator by a preamble to be transmitted, a symbol mapper that converts header and payload data to be applied to the transmission target packet into symbols and outputs the same, a multiplexer that processes an output signal of the transmission-multiplier and an output signal of the symbol mapper to be selectively output through an output end to form a symbol stream in units of packets, and a differential symbol converter that converts the symbol stream output from the multiplexer according to a predetermined differential modulation method and outputs the converted symbol stream.

Abstract: A single-canister underwater stereocamera system with a distance measurement function. In the camera system, a camera drive unit, holding two cameras on its camera base, is set in a parallel space defined between two support plates, and is operable by a motor unit, thus being movable along with the two cameras to the front or back. A lens drive unit, holding two lenses on two lens bases, is set in the parallel space to be operable by the motor unit so as to laterally move the two lenses to the left or right under the guide of a linear guide bearing. The motor unit controls the focus length of each of the two cameras and the moving distance of the two lenses at the same time. In the camera system, the actual distance of an underwater target object from the system is measured by sensing a rotated position of the encoder of the motor unit, taking advantage of the fact that the actual distance of the target object has a functional relation of 1:1 with the focus length of each of the cameras.

Abstract: A single-canister underwater stereocamera system with a distance measurement function is disclosed. In the camera system, a camera drive unit, holding two cameras on its camera base, is set in a parallel space defined between two support plates, and is operable by a motor unit, thus being movable along with the two cameras to the front or back. A lens drive unit, holding two lenses on two lens bases, is set in the parallel space to be operable by the motor unit so as to laterally move the two lenses to the left or right under the guide of a linear guide bearing. The motor unit controls the focus length of each of the two cameras and the moving distance of the two lenses at the same time. In the camera system, the actual distance of an underwater target object from the system is measured by sensing a rotated position of the encoder of the motor unit, taking advantage of the fact that the actual distance of the target object has a functional relation of 1:1 with the focus length of each of the cameras.