Adaptive Information Rate Communication via Dynamic TDM
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing broadband communication systems face inefficiencies when serving a wide range of user terminals with varying antenna sizes and link conditions, as they often operate with a single carrier, leading to excess margin wastage and limited adaptability, especially for smaller mobile terminals.
Innovation Solution
The system employs adaptive information rate (AIR) technology, dynamically adjusting the information rate for each user terminal via a continuous time division multiplexed (TDM) signal, using a single carrier to maintain a predetermined margin above the threshold energy-to-noise spectral density ratio, while maintaining a constant occupied signal bandwidth through spread-spectrum modulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a single carrier is used with fixed information rate for all user terminals, then the power amplifier can operate at maximum saturated power level, but user terminals with better link conditions experience excess margin wastage and reduced communication efficiency
Solution Approach 1:
The patent implements dynamic information rate adjustment where the base station continuously adapts the forward link information rate based on real-time link conditions of each user terminal. This allows the system to transition from a static single-rate approach to a dynamic multi-rate approach, optimizing both power efficiency and communication efficiency by matching the information rate to actual channel conditions.
Solution Approach 2:
The patent changes the information rate parameter dynamically based on link conditions. By adjusting the information rate according to terminal capabilities and channel quality, the system can allocate higher rates to terminals with better conditions (reducing wastage) while maintaining adequate rates for terminals with poorer conditions, thus resolving the contradiction between power efficiency and communication efficiency.
2Reliability
If the forward link waveform is selected to close the communication link with the most disadvantaged user terminal, then all user terminals can successfully receive the signal, but advantaged user terminals operate with excess margin and communication efficiency is reduced
Solution Approach 1:
The patent segments the user terminal population into different groups based on their link conditions (disadvantaged, intermediate, advantaged). By identifying and categorizing terminals according to their specific requirements and capabilities, the system can apply differentiated information rates to each segment, ensuring reliable communication for disadvantaged terminals while optimizing efficiency for advantaged terminals.
Solution Approach 2:
The patent applies local quality by tailoring the information rate to the specific conditions of each user terminal or terminal group. Instead of a uniform approach, the system adjusts the forward link waveform parameters locally for each terminal based on its antenna size, location, and channel conditions, thereby optimizing both reliability for disadvantaged terminals and efficiency for advantaged terminals.
3Productivity
If adaptive coding and modulation is used to adjust forward error correction and signal modulation, then performance improves for standard VSAT terminals, but smaller mobile terminals with non-standard antenna sizes cannot effectively utilize these adjustments
Solution Approach 1:
The patent achieves universality by creating a single forward link communication system that can effectively serve diverse terminal types including standard VSAT terminals, smaller mobile terminals, and terminals with varying antenna sizes. By using dynamic information rate adjustment based on actual link conditions rather than assuming standard terminal configurations, the system becomes universally applicable to all terminal types while maintaining optimal performance across the board.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A system and method for communicating information from a base station to one or more user terminals via a forward link to a relay and distribution device is provided. The method includes determining a separate information rate for information to be transmitted from the base station to each of the user terminals. Each information rate is determined to allow successful communication with the respective user terminal and to provide a predetermined amount of link margin above a threshold energy-to-noise ratio (Eb/No) in the forward link. The method additionally includes formatting data received at the base station into a continuous time division multiplexed (TDM) data stream that includes a plurality of data frames to be transmitted to the user terminals. Each data frame is formatted to have the determined information rate of the respective user terminal destine to receive the data frame. The TDM data stream is transmitted using a single carrier of the forward link. Furthermore, the method includes continuously and dynamically adjusting the information rate of subsequent data frames for each user terminal to maintain successful communication and maintain the predetermined amount of margin as operating conditions of each user terminal change.