PLS Header Coding for Expanded Modulation Signaling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current modulation and coding schemes in DVB-S2 standards are inadequate for supporting terminals with low signal-to-noise ratios and lack sufficient granularity for modern broadband satellite communications, leading to inefficiencies in header signaling and operational range limitations.
Innovation Solution
A method involving the generation of a mode indicator field to distinguish between different modulation and coding modes, where the mode indicator field is encoded and modulated using different phases, such as π/2 BPSK and 90-degree out-of-phase modulation, to expand the operational range and granularity of user terminals without increasing bandwidth overhead.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the physical layer header size is increased to directly support expanded modulation and coding scheme sets, then the signaling capability is improved, but the bandwidth efficiency deteriorates due to increased signaling overhead
Solution Approach 1:
The patent embeds additional signaling information within the existing PLS header structure by utilizing unused or sparsely used bit positions in the current header format. This nesting approach allows expanded modulation and coding scheme sets to be signaled without increasing the overall header size, thereby maintaining bandwidth efficiency while improving signaling capability
Solution Approach 2:
The patent reinterprets and reassigns the meaning of existing header parameters to encode additional modulation and coding scheme information. By changing how existing parameters are utilized rather than adding new parameters, the system achieves expanded signaling capability without increasing header overhead
2Adaptability or versatility
If two different scramblers are employed to signify additional bits, then the signaling range is expanded, but the system performance deteriorates due to cross-correlation between scramblers
Solution Approach 1:
The patent extracts the additional signaling function from the data payload and relocates it to the PLS header section. This separation allows the additional bits to be signaled independently through header parameters rather than through scrambler selection, eliminating the cross-correlation problem while maintaining expanded signaling range
Solution Approach 2:
The patent introduces dedicated header parameters as intermediaries to carry additional modulation and coding scheme information. These intermediary parameters act as a bridge between the transmitter and receiver, enabling expanded signaling without requiring multiple scramblers and their associated cross-correlation issues
3Adaptability or versatility
If the DVB-S2 modulation and coding schemes are used, then the standard compatibility is maintained, but the operational range and granularity are insufficient for modern broadband satellite communications
Solution Approach 1:
The patent makes the existing DVB-S2 PLS header structure multi-functional by enabling it to signal both traditional modulation and coding schemes and expanded schemes within the same framework. This universal approach allows the system to maintain standard compatibility while supporting extended operational ranges through enhanced parameter encoding
Solution Approach 2:
The patent introduces dynamic parameter assignment where header parameters can be flexibly configured to represent different modulation and coding schemes based on system requirements. This dynamic approach allows the standard-compliant header structure to adaptively support both legacy and expanded schemes, achieving extended operational range without sacrificing standard compliance
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables efficient header signaling and supports expanded modulation and coding schemes, enhancing the operational range and granularity of user terminals in broadband satellite communications networks while maintaining system efficiency.
Implementation Method 1
A method involving the generation and modulation of a mode indicator field using two distinct phases, where the first phase is π/2 BPSK and the second phase is out of phase by approximately 90 degrees
Data Source
AI summary
An approach is provided for an improved coding approach for efficient header signaling in broadband communications networks, to provide support of expanded modulation and coding scheme sets that facilitate an expansion of the operational ranges of user terminals within such networks and finer granularity within such operational ranges. A mode indicator field of a frame header identifies a modulation/coding mode applied to a data payload of the data frame. The modulation/coding mode is one of either a first or second set of modulation/coding modes. The mode indicator field is encoded and modulated. When the modulation/coding mode is one of the first set, the modulation of the encoded mode indicator field is applied in a first mode, and when the modulation/coding mode is one of the second set, the modulation of the encoded mode indicator field is applied in a second mode.