Broadcast Signal Data Pipes for Robust Multi-Service OFDM
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current digital broadcast systems face challenges in efficiently transmitting and receiving large amounts of data, particularly in providing multiple broadcast services through the same RF signal bandwidth, ensuring robustness and flexibility, especially for mobile reception equipment.
Innovation Solution
The method involves formatting input streams into Data Pipe (DP) data, Low-Density Parity-Check (LDPC) encoding, bit interleaving, mapping onto constellations, and modulating using Orthogonal Frequency Division Multiplexing (OFDM) to transmit broadcast signals, including Audio/Video and service guide data in ISO base media file formats, allowing for synchronization of non-real-time and real-time content.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple broadcast services are transmitted through the same RF signal bandwidth, then transmission efficiency is improved, but data transmission robustness deteriorates
Solution Approach 1:
The broadcast data stream is segmented into multiple Data Pipes (DPs), where each DP carries a specific service or service component. This segmentation allows independent encoding and modulation for each service, enabling robustness control per service while multiplexing multiple services in the same RF bandwidth through time-division multiplexing of the DPs.
Solution Approach 2:
Different encoding schemes, code rates, and modulation methods are applied to different Data Pipes based on their specific requirements. For example, services requiring higher robustness can use lower code rates and more robust modulation, while services prioritizing throughput can use higher code rates. This local optimization resolves the contradiction by allowing simultaneous transmission of multiple services with different robustness requirements in the same bandwidth.
2Reliability
If data is classified by components and transmitted as separate data pipes, then service quality control is improved, but system complexity increases
Solution Approach 1:
The system segments broadcast data into standardized Data Pipe structures, each with defined headers and payload formats. This segmentation enables independent quality control for each service component while maintaining a uniform processing framework that limits complexity growth through standardization.
Solution Approach 2:
The Data Pipe structure serves multiple functions: it acts as a container for service data, a carrier for quality control parameters, a unit for error correction coding, and a basis for time-division multiplexing. This multi-functionality reduces the need for separate mechanisms for each function, thereby controlling system complexity while enabling comprehensive service quality control.
3Adaptability or versatility
If digital broadcast signals include large amounts of video/audio data and additional data, then service functionality is improved, but transmission efficiency deteriorates
Solution Approach 1:
The large volume of broadcast data is segmented into fixed-size Data Pipes with structured formats including headers and payloads. This segmentation enables efficient packing and multiplexing of diverse data types (video, audio, service guide data) while maintaining organized access and reducing overhead, thereby improving transmission efficiency without sacrificing service functionality.
Solution Approach 2:
The system employs variable code rates and modulation schemes for different Data Pipes based on their data characteristics and priority. By dynamically adjusting these parameters, the system optimizes transmission efficiency for each type of data while maintaining the ability to provide diverse services with different quality requirements.
Data Source
AI summary
The present invention provides a method of transmitting broadcast signals. The method includes, formatting input streams into Data Pipe (DP) data, Low-Density Parity-Check (LDPC) encoding the DP data according to a code rate, bit interleaving the LDPC encoded DP data, mapping the hit interleaved DP data onto constellations, building at least one signal frame including the mapped DP data, and modulating data in the built signal frame by an Orthogonal Frequency Division Multiplexing (OFDM) method and transmitting the broadcast signals having the modulated data, wherein the input streams include Audio/Video (A/V) data and service guide data, and wherein the Audio/Video (A/V) data and service guide data are included in first ISO base media file format (ISOBMFF) files.