Abstract: In the present invention, in classifying modulation types of a plurality of modulation signals by using a classifier (an artificial neural network model based on machine learning), the classifier may classify the modulation types of the modulation signals by using pieces of I/Q data, sampled with one sampling frequency, as input data, and thus, may quickly classify the modulation signals.

Abstract: In the present invention, in classifying modulation types of a plurality of modulation signals by using a classifier (an artificial neural network model based on machine learning), the classifier may classify the modulation types of the modulation signals by using pieces of I/Q data, sampled with one sampling frequency, as input data, and thus, may quickly classify the modulation signals.

Abstract: A directive direction finding apparatus may comprise: a directivity-enabled antenna array in which a constituent antenna or antenna subarray has directivity in the same direction; an RF/IF receiver connected to the directivity-enabled antenna array; a digital receiver connected to the RF/IF receiver; a direction finder connected to the digital receiver; a directivity control unit to control an operation of the directivity-enabled antenna array; and a transport/control interface connected to the direction finder and to manage control and operation of the directivity-enabled antenna array, the RF/IF receiver, the digital receiver, the direction finder and the directive control unit.

Abstract: There are provided a multi-bay antenna apparatus and an operation method thereof. A multi-bay antenna apparatus may include a first section, a first array antenna mounted in the first section to receive a signal in a predetermined frequency band, a second section movably coupled with the first section, and a second array antenna mounted in the second section to receive a signal in a predetermined frequency band.

Abstract: A dipole antenna fed by a planar balun includes a first radiation element and a second radiation element respectively corresponding to poles of the dipole antenna, at least one dipole support column configured to connect the first radiation element and the second radiation element and to fix a gap between the first radiation element and the second radiation element, a planar balun connected to the first radiation element and the second radiation element and configured to feed the first radiation element and the second radiation element, and a balun housing coupled to the dipole support column and enclosing the planar balun.

Abstract: A dipole antenna fed by a planar balun includes a first radiation element and a second radiation element respectively corresponding to poles of the dipole antenna, at least one dipole support column configured to connect the first radiation element and the second radiation element and to fix a gap between the first radiation element and the second radiation element, a planar balun connected to the first radiation element and the second radiation element and configured to feed the first radiation element and the second radiation element, and a balun housing coupled to the dipole support column and enclosing the planar balun.

Abstract: There are provided a multi-bay antenna apparatus and an operation method thereof. A multi-bay antenna apparatus may include a first section, a first array antenna mounted in the first section to receive a signal in a predetermined frequency band, a second section movably coupled with the first section, and a second array antenna mounted in the second section to receive a signal in a predetermined frequency band.

Abstract: An apparatus for calculating a reception time of a wireless communication signal is disclosed. The apparatus includes a downconverted signal generator configured to generate a downconverted signal, a baseband signal, by downconverting a frequency of a signal received from a transmission source, a modulated signal generator configured to generate a modulated signal by multiplying the downconverted signal by a randomly generated reference signal, a time difference calculator configured to calculate a time difference between the modulated signal and the reference signal by cross-correlating the modulated signal and the reference signal, and a reception time calculator configured to calculate a reception time of the signal received from the transmission source using a point in time at which the reference signal is generated and the time difference between the modulated signal and the reference signal.

Abstract: An apparatus for calculating a reception time of a wireless communication signal is disclosed. The apparatus includes a downconverted signal generator configured to generate a downconverted signal, a baseband signal, by downconverting a frequency of a signal received from a transmission source, a modulated signal generator configured to generate a modulated signal by multiplying the downconverted signal by a randomly generated reference signal, a time difference calculator configured to calculate a time difference between the modulated signal and the reference signal by cross-correlating the modulated signal and the reference signal, and a reception time calculator configured to calculate a reception time of the signal received from the transmission source using a point in time at which the reference signal is generated and the time difference between the modulated signal and the reference signal.

Abstract: Disclosed is a digital radio frequency (RF) signal receiving apparatus including an RF filter configured to convert multichannel wireless signals received through an antenna into signals available for digital sampling, an analog-to-digital converter configured to perform digital sampling on the multichannel wireless signals converted by the RF filter, a digital processor configured to perform filtering on each of the digital-sampled multichannel wireless signals into a plurality of bandwidth signals within a maximum bandwidth range simultaneously, and down-convert the filtered multichannel wireless signals to be signals in a baseband, a data formatter configured to format the down-converted signals based on an input/output data form of transmission interfaces, and a data transmitter configured to simultaneously transmit each of formatted signals to a corresponding processing platform.

Abstract: An apparatus for radio direction finding, the apparatus comprising: a receiver configured to receive target signals to be subjected to the direction finding of signal sources, which are acquired by an antenna array; a channel profiler configured to produce profiles of the target signals received through the receiver; a pre-analyzer configured to preemptively process in a narrowband the wideband target signals based on the profiles that are produced by the channel profiler to produce pre-analyzed information for the wideband target signals; and a direction finder configured to perform the direction finding on the signal sources using the pre-analyzed information and the profilers of the target signals.

Abstract: Provided herein is a method and apparatus for realizing a frequency-spatial filter with variable bandwidth, the method including generating M number of FFT channel blocks having N number of channels by performing an N point FFT (Fast Fourier Transform) processing using M number of array antenna inputs; combining some of the N number of channels of each FFT channel block according to a frequency bandwidth variable parameter value; combining some of spatial response vector channels in a combined channel of each FFT channel block according to a spatial bandwidth variable parameter value; and combining all the channels and outputting the same.

Abstract: Provided herein is a method and apparatus for realizing a frequency-spatial filter with variable bandwidth, the method including generating M number of FFT channel blocks having N number of channels by performing an N point FFT (Fast Fourier Transform) processing using M number of array antenna inputs; combining some of the N number of channels of each FFT channel block according to a frequency bandwidth variable parameter value; combining some of spatial response vector channels in a combined channel of each FFT channel block according to a spatial bandwidth variable parameter value; and combining all the channels and outputting the same.

Abstract: An apparatus is used for modulation classification of unknown input signal in a wireless communication system. The apparatus includes a signal classification unit configured to classify the input signal into a PSK signal and an FSK signal and a modulation index decision unit configured to decide a modulation index for the PSK signal and the FSK signal classified by the signal classification unit.

Abstract: An apparatus for radio direction finding, the apparatus comprising: a receiver configured to receive target signals to be subjected to the direction finding of signal sources, which are acquired by an antenna array; a channel profiler configured to produce profiles of the target signals received through the receiver; a pre-analyzer configured to preemptively process in a narrowband the wideband target signals based on the profiles that are produced by the channel profiler to produce pre-analyzed information for the wideband target signals; and a direction finder configured to perform the direction finding on the signal sources using the pre-analyzed information and the profilers of the target signals.

Abstract: An apparatus is used for modulation classification of unknown input signal in a wireless communication system. The apparatus includes a signal classification unit configured to classify the input signal into a PSK signal and an FSK signal and a modulation index decision unit configured to decide a modulation index for the PSK signal and the FSK signal classified by the signal classification unit.

Abstract: Provided is a method of estimating a symbol. The method may include deriving phase components of input data, applying a second order differentiation to the phase components to obtain a second order differential phase vector, and estimating symbols corresponding to the input data using the second order differential phase vector.

Abstract: Provided is a method of estimating a symbol. The method may include deriving phase components of input data, applying a second order differentiation to the phase components to obtain a second order differential phase vector, and estimating symbols corresponding to the input data using the second order differential phase vector.