Co-frequency Full-duplex Antenna Self-interference Cancellation
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Solution Overview
Problem
Existing co-frequency full-duplex communication technologies face challenges in eliminating self-interference without active devices and suffer from poor interference elimination effects due to random errors in signals transmitted by multiple antennas.
Innovation Solution
A co-frequency full-duplex antenna structure that includes a receiving antenna, a transmitting antenna, and a signal reflection apparatus with a dielectric layer and a reflection surface, which reflects signals to create a path difference of an odd number of half wavelengths, eliminating self-interference without active devices and ensuring equal distortion and loss for reflected and direct signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If two transmitting antennas are used to eliminate self-interference, then interference elimination effect is improved, but device complexity increases and signal consistency deteriorates due to random errors in different antenna channels
Solution Approach 1:
The patent segments the single transmitting antenna's signal path into two separate paths: a direct path and a reflected path. By using a reflector to create a virtual second transmitting antenna, the signal is divided into two components that can interfere with each other constructively or destructively at the receiving antenna, enabling self-interference cancellation without requiring two physical transmitting antennas.
Solution Approach 2:
The patent introduces a reflector as an intermediary element between the transmitting antenna and the receiving antenna. This reflector creates a reflected signal path that acts as a mediator to generate a cancellation signal. The reflector enables the creation of a virtual transmitting antenna image, which provides the second signal path needed for interference elimination without adding complex active devices.
2Object-affected harmful factors
If two transmitting antennas are used to eliminate self-interference, then interference elimination effect is improved, but manufacturing precision requirements increase due to signal consistency issues
Solution Approach 1:
The patent uses the reflector to create a virtual copy or image of the transmitting antenna. This virtual copy produces a reflected signal that is a predictable copy of the original transmitted signal, modified only by the known reflection path characteristics. This copying approach ensures signal consistency because both the direct and reflected signals originate from the same physical antenna with identical transmission characteristics, eliminating the random errors that would exist between two separate physical antennas.
Solution Approach 2:
The single transmitting antenna serves dual purposes: it transmits the original signal directly to the receiving antenna, and simultaneously serves as the source for the reflected cancellation signal. The antenna essentially serves itself by providing both the useful signal and the interference cancellation signal, eliminating the need for a second independent transmitting antenna and its associated signal consistency problems.
3Object-affected harmful factors
If a signal reflection apparatus with dielectric layer is added, then self-interference elimination is improved, but device complexity increases
Solution Approach 1:
The patent uses a dielectric layer with specific dispersion properties to modify the electrical parameters of the reflected signal path. By carefully selecting the dielectric material and its thickness, the patent controls the phase and amplitude characteristics of the reflected signal to achieve optimal cancellation. This parameter-based approach allows for precise control of the interference elimination effect without requiring complex active devices or multiple antenna elements.
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 solution effectively eliminates self-interference and reduces residual signal interference, improving communication efficiency by maintaining equal power and minimizing random errors, while simplifying the antenna structure and reducing costs.
Implementation Method 1
a signal reflection apparatus comprising a reflection surface configured to reflect the signal transmitted by the transmitting antenna
Implementation Method 2
comprising a dielectric layer of a specific dispersion property configured to be arranged on the path of the reflected signal to reduce a wavelength difference between signals of different frequencies in the broadband signal
Implementation Method 3
one of the two transmission signals is superimposed on the other of the two transmission signals at the receiving antenna 104. As a phase difference of the two transmission signals is π due to a path difference of a half of the wavelength, the interference of the superimposed transmission signals can be eliminated
Data Source
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AI summary
The present disclosure provides a co-frequency full-duplex antenna structure and an electronic apparatus for wireless communications. The co-frequency full-duplex antenna structure includes a receiving antenna, a transmitting antenna for transmitting a signal of a predetermined wavelength, and a signal reflection apparatus for reflecting the signal transmitted by the transmitting antenna, so as to realize that a path difference between a reflected signal formed when the signal transmitted by the transmitting antenna reaches the receiving antenna after being reflected and a direct signal formed when the signal transmitted by the transmitting antenna directly reaches the receiving antenna is an odd number of times as much as one half of the predetermined wavelength. In the technical solution of the present disclosure, without adding an active device, elimination of self-interference of antennas can be realized, and the problems of a poor effect of interference elimination and strong interference of residual signals due to the fact that there are random errors in signals transmitted by two transmitting antennas can be also avoided.