Abstract:
계층 변조 기법이 적용된 방송 시스템에서 간섭을 제거하는 장치는 서비스 제공 신호와 서비스 제공 신호에 새로 추가되는 신호를 포함하는 계층 변조 신호를 복조한다. 다음, 간섭 제거 장치는 서비스 제공 신호를 복조하여 서비스 제공 데이터를 생성하고, 서비스 제공 데이터를 특정 신호로 변조하여, 복조한 계층 변조 신호에서 특정 신호에 대응하는 간섭 신호를 제거한다.
Abstract:
PURPOSE: Data processing apparatus and method for a digital broadcasting system are provided to enable users to change partial information on a fast information channel instead of re-multiplexing the ETI(ensemble transmission interface). CONSTITUTION: A data processing apparatus for a digital broadcasting system comprises the following: a frame separating unit(520) decoding a first ETI(ensemble transmission interface) frame, and separating FIC(first fast information channel) data and non-FIC data forming the first ETI frame; an FIC changing unit(530) changing the first FIC data into new second FIC data; and a frame formation unit(540) forming a second ETI frame based on the second FIC data and the non-FIC data.
Abstract:
방송 신호 전송 방법에서, 전송 프레임은 기존의 지상파 DMB 신호의 구조와 동일한 구조를 가지며, 기본 계층 서비스 스트림을 포함하는 전송 프레임은 기본 계층으로 변조되고, 강화 계층 서비스 스트림을 포함하는 전송 프레임은 강화 계층으로 변조된다. 이때, 강화 계층 서비스 스트림은 강화 계층 서비스를 제공하기 위하여 기본 계층 서비스 스트림에 포함되지 않은 부가적인 데이터로 구성된다. 이와 같이 하면, 기존의 지상파 DMB와 호환가능하면서도, 고전송 효율을 요구하는 고품질의 서비스를 제공할 수 있다. 이때, 고전송 효율은 기존의 지상파 DMB보다 높은 데이터 전송률을 의미한다. 지상파 DMB, 방송, 계층적 변조 방식, 고품질 서비스, 비디오 서비스
Abstract:
본 발명은 계층 변조가 적용된 지상파 DMB 시스템에서의 하이브리드 변조 방법 및 장치에 관한 것이다. 이를 위하여, 본 발명은 LP 신호에서 MSB 비트 및 LSB 비트에 설정된 진폭 변조 값 및 위상 변화 값에 따라, HP 신호의 진폭 및 HP 신호의 위상을 변조시킨 뒤, 진폭 변조된 신호와 위상 변조된 신호를 결합하여 송출하는 변조 방법을 제공한다. 또한, 본 발명은 LP 신호에서 MSB 비트 및 LSB 비트의 설정 값을 확인하는 수단; HP 신호의 진폭을 변조시키는 수단; HP 신호의 위상을 변조시키는 수단; 및 진폭 변조된 신호와 위상 변조된 신호를 결합하여 송출하는 수단을 포함한다. 본 발명에 의하면, 지상파 DMB 시스템에서 LP 신호에 고정 진폭 변조와 차동 이진 위상 변조를 결합한 하이브리드 변조 방식을 사용함으로써 성상 간의 거리가 크게 나타나며, 기존의 지상파 DMB 시스템의 DQPSK 변조에서 발생하는 위상 모호성 문제를 해결할 수 있다. DMB, T-DMB, 계층 변조, 기본 계층, 향상 계층, 하이브리드 변조
Abstract:
PURPOSE: A demodulation method at a round wave digital multimedia broadcasting system with applying hybrid modulation and a device thereof are provided to improve the channel distortion of fixed amplitude modulation and differential phase modulation by using a hybrid modulation method. CONSTITUTION: A FFT module(100) transforms a signal of the time area to the signal of the frequency area. An OFDM demodulator(200) performs the OFDM demodulation about the signal which is Fourier transformed. A hybrid demodulator(300) restores a transmission signal by applying fixing to the former state the transmission signal by applying fixed amplitude modulation and differential phase modulation. A HP signal processing unit(400) comprises a DQPSK demodulator(410), a frequency deinterleaver(420), a demapper(430), a transfer frame demultiplexer(440) and a viterbi decoder(450). A LP signal processing unit comprises the frequency deinterleaver(510), the demapper(520), a transfer frame demultiplexer(530) and the viterbi decoder(540).
Abstract:
PURPOSE: A hybrid modulation method and structure are provided to overcome a phase ambiguity problem which is generated in differential quadrature phase shift keying modulation by combining coherent amplitude modulation and differential binary phase shift keying. CONSTITUTION: A bit testing unit(310) confirms the set values of a first bit and a second bit from first signal which is inputted for hierarchical modulation. A first modulation unit(320) modulates the amplitude of the second signal which is inputted for a mobile broadcasting service based on the amplitude modulated value of the first bit. A second modulation unit(330) modulates the phase of the second signal in correspond with the set value of the second bit. A transmission unit combines and transmits the amplitude modulated signal and the phase modulated signal. A bit value confirmation unit(322) confirms the value of the first bit.
Abstract:
PURPOSE: A method and an apparatus for transmitting modulation mode detection signal are provided to improve the transmission rate of data using a plurality of modulation methods for a mobile broadcasting system. CONSTITUTION: A first signal processing unit(100) processes first signal which is inputted for a mobile broadcasting service. A second signal processing unit(200) processes second signal which is inputted for hierarchical modulation. A sequence insertion unit(300) combines the first signal and the second signal and divides the combined signal according to the pre-set time interval. The sequence insertion unit inserts a sequence for encoding/decoding into the divided signal. A signal detection module(350) detects a signal from the combined signal, which the hierarchical modulation is not applied, as third signal.
Abstract:
An apparatus and a method for equalizing the reception channel in an OFDM(Orthogonal Frequency Division Multiplexing) transmission system and a DMB(Digital Multimedia Broadcasting) receiving apparatus applying the same are provided to improve the performance of mobile reception in a transmission system in which pilot signal is not used. A channel estimator(520) estimates channel as a symbol unit with the reference signal received from the standard signal creation part(550). A channel filtering part(530) removes the noises of the presumed channel value. A channel equalization part(540) equalizes the channel by using the estimation channel value. The channel estimator estimates the PRS(Phase Reference Symbol) of the received frame by the reference signal.
Abstract:
A method for multiplexing frame of digital broadcasting signal, apparatus thereof, and transmission apparatus are provided to fit transmission synchronization of a plurality of transmission frames including a service stream about an identical service without a separate field. An apparatus for multiplexing frame of digital broadcasting signal comprises a first buffer(611), a second buffer(612), a time comparison processing unit(630), a first frame generator(651), a second frame generator(652), and a time stamp generator(660). The first buffer stores a first service stream received from outside. The second buffer stores a second service stream received from outside. The time comparison processing unit compares a first service time data about the first service stream with a second service time data about the second service stream. The first frame generator outputs a first frame including the first service stream outputted in the first buffer. The second frame generator outputs a second frame including the second service stream outputted in the second buffer. The time stamp generator generates a first transmission time data comprised in a time stamp field of the first frame and a second transmission time data comprised in a time stamp field of the second frame.
Abstract:
An apparatus for receiving hierarchical modulation signal capable of efficiently decoding added signal and method thereof are provided to reduce power consumption of a receiver by reducing complexity of the receiver. A method for receiving hierarchical modulation signal capable of efficiently decoding added signal comprises the following steps: a step for receiving a hierarchical modulation signal having a plurality of layers(S201); a step for generating a first hierarchical modulation signal by differentially demodulating the hierarchical modulation signal(S203); a step for generating a first hierarchical estimated signal by estimating the first hierarchical modulation signal(S209); a step for the first hierarchical estimated signal by modulating the first hierarchical estimated signal(S211); and a step for extracting a second hierarchical modulation signal in the hierarchical modulation signal based on the first hierarchical estimated signal(S213).