Intermediate-Frequency Repeater System for Low-Loss Cable Links
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing repeater systems for millimeter-wave frequencies face significant signal attenuation and switching losses due to coaxial cables and the need for synchronization in TDD mode, limiting network coverage and increasing installation costs.
Innovation Solution
The repeater system converts radio signals to intermediate frequencies for transmission between separate donor and service units, using frequency converters and switches to minimize cable length and reduce signal attenuation, and employs adjustable gain amplifiers to avoid oscillations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If radio signals are transmitted at millimeter-wave frequencies, then data rates are increased, but signal attenuation and propagation losses are significantly increased
Solution Approach 1:
The system segments the millimeter-wave signal transmission into two stages: first converting to intermediate frequency for low-loss cable transmission, then converting back to millimeter-wave for final transmission. This segmentation allows each stage to operate in its optimal frequency range, achieving both high data rates and low signal attenuation
Solution Approach 2:
The patent introduces an intermediate frequency as a mediator between the baseband signal and the millimeter-wave signal. This intermediate frequency serves as a bridge that enables efficient cable transmission while preserving the capability for high-speed wireless transmission, effectively mediating between the conflicting requirements of low attenuation and high data rate
2Ease of operation
If coaxial cables are used to connect donor and service antennas, then signal transmission is enabled, but frequency-dependent signal attenuation increases with frequency and cable length
Solution Approach 1:
The system changes the frequency parameter of the signal from millimeter-wave to intermediate frequency during cable transmission. This parameter change fundamentally alters the cable's attenuation characteristics, reducing signal loss from potentially unacceptable levels to manageable levels that can be compensated by amplifiers
3Adaptability or versatility
If TDD mode is used for repeater operation, then frequency utilization is improved, but synchronization requirements and switching losses increase
Solution Approach 1:
The patent extracts the synchronization function from the millimeter-wave signal path and implements it separately at the intermediate frequency stage. This extraction allows synchronization to be established once at a lower frequency where it is easier to manage, eliminating the need for complex continuous synchronization at millimeter-wave frequencies
4Area of stationary object
If repeater gain is increased to compensate for cable losses, then signal coverage is improved, but oscillations may occur between transmit and receive paths
Solution Approach 1:
The intermediate frequency converter acts as an isolating intermediary between the receive and transmit paths. This intermediary breaks the direct feedback loop that could cause oscillations, allowing high gain to be used for extended coverage while maintaining system stability through the frequency conversion barrier
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 reduces signal loss and energy consumption, enabling effective network coverage with reduced installation complexity and cost.
Implementation Method 1
The repeater system comprises a first frequency converter unit (400), referred to as a donor unit, and a second frequency converter unit (450), referred to as a service unit
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a repeater system (10) for forwarding radio signals. The repeater system (10) comprises a donor unit (400) for converting the frequencies of the radio signals from the transmission frequency to an intermediate frequency (ZF); a server unit (450) for converting the converted radio signals from the intermediate frequency (ZF) to the transmission frequency; and a cable (420), which connects the donor unit (400) and the service unit (450) and transmits the converted radio signals over a distance between the donor unit (400) and the service unit (450) at the intermediate frequency (ZF). The donor unit (400) has an uplink donor antenna (40b) and a separate downlink donor antenna (40c) and/or the service unit (450) has an uplink service antenna (50b) and, at the same time, a separate downlink service antenna (50a).