摘要:
A transmission apparatus according to an exemplary embodiment of the present invention comprises a serial/parallel (S/P) converter for converting an input bit stream into a plurality of symbols each including 3 bits, a differential modulator for generating differential encoded symbols by applying π/4 phase rotation to each of the symbols, up-samplers for up-sampling the differential encoded symbols, filters for filtering the up-sampled symbols, digital/analog (D/A) converters for converting the filtered symbols into analog signals, and a quadrature modulator for performing quadrature modulation on the converted analog signals.
摘要:
A transmission apparatus according to an exemplary embodiment of the present invention comprises a serial/parallel (S/P) converter for converting an input bit stream into a plurality of symbols each including 3 bits, a differential modulator for generating differential encoded symbols by applying π/4 phase rotation to each of the symbols, up-samplers for up-sampling the differential encoded symbols, filters for filtering the up-sampled symbols, digital/analog (D/A) converters for converting the filtered symbols into analog signals, and a quadrature modulator for performing quadrature modulation on the converted analog signals.
摘要:
A modulation apparatus performs modulation in which a signal wave form is positioned at the front part of an entire symbol duration or the latter part of the entire symbol duration based on a first bit of the bit information to generate a modulation symbol including a silent signal duration in which there is no signal waveform. Particularly, the method delays a signal corresponding to a quadrature-phase signal axis by a predetermined time, thereby cancelling a phase difference between symbols.
摘要:
A modulation apparatus performs modulation in which a signal wave form is positioned at the front part of an entire symbol duration or the latter part of the entire symbol duration based on a first bit of the bit information to generate a modulation symbol including a silent signal duration in which there is no signal waveform. Particularly, the method delays a signal corresponding to a quadrature-phase signal axis by a predetermined time, thereby cancelling a phase difference between symbols.
摘要:
Disclosed is a method for modulating and demodulating data. The method composes symbols by grouping a plurality of symbols for pulse position modulation to newly add symbol compositions to fixed symbols used for the pulse position modulation of the related art. Further, the method uses grouped symbols to improve data transmission rate as the average amount of information increases.
摘要:
A modulation device uses two base signal axes including a cosine function and two base signal axes including a sine function to modulate bit information and generate a modulation symbol. Accordingly, the frequency efficiency characteristic is improved while maintaining a great power efficiency characteristic.
摘要:
A method of generating a packet for low energy critical infrastructure monitoring (LECIM) wireless communication is provided. The method includes steps of generating a first bit string by multiplexing a physical layer header (PHR) bit and a physical layer service data unit (PSDU) bit; convolution encoding the first bit string; interleaving the convolution-encoded first bit string; generating a second bit string by multiplexing the interleaved first bit string with a synchronization header (SHR) bit; and modulating the second bit string with a frequency shift keying (FSK) method and a position-based FSK method.
摘要:
A method of generating a packet for low energy critical infrastructure monitoring (LECIM) wireless communication is provided. The method includes steps of generating a first bit string by multiplexing a physical layer header (PHR) bit and a physical layer service data unit (PSDU) bit; convolution encoding the first bit string; interleaving the convolution-encoded first bit string; generating a second bit string by multiplexing the interleaved first bit string with a synchronization header (SHR) bit; and modulating the second bit string with a frequency shift keying (FSK) method and a position-based FSK method.
摘要:
A lighting apparatus is disclosed. The disclosed lighting apparatus omni-directionally radiates light emitted from a light emitting diode (LED) in a uniform light intensity. The lighting apparatus may include at least one LED and a reflector to reflect light emitted from the at least one LED. The reflector may include openings that are positioned to correspond to a position of a respective LED. The LED may emit light in a first direction and the reflector may reflect the light in a second direction such that a difference in light intensity at any angle within a first range between 0° to 135° with respect to the first direction is less than or equal 20% of an average light intensity of the entire range, and a light flux within a second range between 135° to 180° is greater than or equal to 5% of the total flux.
摘要:
A method for clustering data based convex optimization is provided. The method includes the steps of: obtaining an optimal feasible solution that satisfies given strong duality using convex optimization for an objective function; and clustering data by extracting eigenvalue from the obtained optimal feasible solution.