Preamble Phase Rotation for Differential Modulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional differential modulation packet data communication lacks the ability to transmit additional information effectively, relying solely on a predetermined preamble for synchronization and channel distortion compensation, which limits data transmission efficiency.
Innovation Solution
An apparatus and method that phase-rotate the preamble based on additional information, incorporating a phase rotator, transmission-multiplier, symbol mapper, multiplexer, and differential symbol converter to integrate additional information into the preamble, allowing for increased data transmission rates by including packet type, generation method, or length information.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of information
If a predetermined preamble is used for synchronization and channel distortion compensation, then synchronization and channel distortion compensation are achieved, but additional information cannot be transmitted effectively
Solution Approach 1:
The preamble is designed to serve multiple functions: traditional synchronization and channel distortion compensation, plus transmission of additional information such as packet type, generation method, and length information. By making the preamble multi-functional, the system eliminates the need for separate additional information fields in packet headers, thereby resolving the contradiction between maintaining synchronization functionality and enabling additional information transmission.
Solution Approach 2:
The patent introduces a new dimension to the preamble by phase-rotating it based on additional information. Instead of using the preamble only for its traditional purposes, the system encodes additional information into the preamble's phase characteristics. This dimensional expansion allows the preamble to carry both synchronization data and additional information without increasing packet header length, thus resolving the information transmission limitation.
2Loss of information
If packet headers are used to transmit additional information, then additional information can be transmitted, but data transmission efficiency decreases due to lengthy headers
Solution Approach 1:
The patent merges the transmission of additional information with the preamble structure. Instead of placing additional information in separate packet headers, the system combines packet type, generation method, and length information directly into the preamble through phase rotation. This merging eliminates redundant header fields and reduces overall packet overhead, thereby increasing data transmission efficiency and resolving the contradiction between information transmission and transmission rate.
3Productivity
If conventional differential modulation is used, then data transmission is achieved, but additional information cannot be effectively transmitted
Solution Approach 1:
The patent modifies the differential modulation process by introducing phase rotation as an additional parameter. Instead of using only amplitude and phase modulation for data transmission, the system incorporates phase rotation of the preamble to encode additional information. This parameter expansion allows the differential modulation scheme to carry both data and additional information, resolving the contradiction between data transmission rate and additional information capability.
Data Source
AI summary
Apparatus and method of transmitting a preamble having additional information in differential modulation packet data communication. The apparatus includes a phase rotator that outputs a phase rotation quantity corresponding to additional information to be applied to a transmission target packet, a transmission-multiplier that multiplies the phase rotation quantity output from the phase rotator by a preamble to be transmitted, a symbol mapper that converts header and payload data to be applied to the transmission target packet into symbols and outputs the same, a multiplexer that processes an output signal of the transmission-multiplier and an output signal of the symbol mapper to be selectively output through an output end to form a symbol stream in units of packets, and a differential symbol converter that converts the symbol stream output from the multiplexer according to a predetermined differential modulation method and outputs the converted symbol stream.