Transpositional Modulation Bandwidth Expansion via Amplitude Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing transmission systems face limitations in bandwidth due to regulatory constraints, and earlier methods of generating transpositional modulation signals suffer from amplitude variation errors that require adjustment, which are not effectively addressed by existing demodulators.
Innovation Solution
The method involves combining transpositional modulated signals with fundamental and harmonic carrier signals, using an all-pass filter with voltage-controlled time delay for time-shift modulation, and direct amplitude or angle modulation of ultrasonic or optical beams to increase communication bandwidth within fixed channels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If transpositional modulation is applied to increase information bandwidth, then bandwidth capacity is improved, but amplitude variation errors are introduced that require additional adjustment circuits
Solution Approach 1:
The patent extracts and eliminates the problematic amplitude variation component by introducing a correction signal that is derived from the modulated signal itself. The correction signal is generated through a feedback mechanism that detects amplitude deviations and generates compensating signals to cancel out the variations, thereby removing the harmful effect while preserving the beneficial bandwidth expansion.
Solution Approach 2:
The patent implements a feedback mechanism where the modulated signal is fed back through a correction circuit that generates a correction signal. This correction signal is then combined with the original modulated signal to compensate for amplitude variations. The feedback loop continuously monitors and adjusts the signal to maintain constant amplitude while preserving the transpositional modulation information.
2Quantity of substance
If multiple carrier signals are combined to increase bandwidth, then information capacity is improved, but signal complexity and interference between modulation types increase
Solution Approach 1:
The patent segments the modulation process by separating different modulation types onto different carrier signals. Transpositional modulation is applied to one carrier while amplitude, frequency, and phase modulations are applied to other carriers. This segmentation allows each modulation type to be processed independently through dedicated circuits, reducing the complexity of signal processing while enabling multiple modulation types to coexist without interference.
Solution Approach 2:
The patent creates a universal modulation system where a single transpositional modulator can work with multiple carrier signals of different frequencies. The correction circuits are designed to be frequency-independent, allowing the same basic circuit architecture to handle various carrier frequencies and modulation types. This multi-functionality reduces overall system complexity by eliminating the need for separate correction circuits for each carrier signal.
3Adaptability or versatility
If transpositional modulation is used to add information without affecting amplitude/frequency/phase, then modulation transparency is improved, but existing demodulators cannot detect the added information
Solution Approach 1:
The patent introduces an intermediary conversion process where the transpositional modulation information is converted into a form that existing demodulators can detect. A correction signal is generated that interacts with the modulated signal to create detectable variations. This intermediary mechanism allows the invisible transpositional modulation information to be transformed into detectable forms without affecting the transparency of the original modulation.
Solution Approach 2:
The patent changes the 'detectability color' of the modulation information by transforming it into a different signal characteristic that can be detected by existing demodulators. The correction signal introduces variations in a domain that existing detection circuits are sensitive to, effectively changing the detectability characteristics of the transpositional modulation information while maintaining its transparency properties.
Data Source
AI summary
Systems, methods and devices for transmitting and receiving and demodulating transpositional modulated signals, for increasing information bandwidth of defined communication channels, and for time-delay shifting an input signal in accordance to an input control signal are provided. One such method of increasing the information bandwidth of a defined communication channel includes receiving a first modulated signal having a first carrier signal frequency; receiving a second modulated signal having a second carrier signal frequency, the second modulated signal being modulated with information independent of information modulating the first carrier signal, the second carrier signal frequency being harmonically or sub-harmonically related to the first carrier signal frequency; and combining the first and second signals.