DAC-Based RF Signal Transmission Without Baseband Generators
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Solution Overview
Problem
Conventional RF signal transmission and reception require baseband generators and local oscillators for up conversion and down conversion, leading to complex and costly equipment needs, as well as phase synchronization issues.
Innovation Solution
The use of a digital-to-analog converter (DAC) to generate RF signals directly in the RF spectrum, eliminating the need for baseband generators and local oscillators, and allowing for phase shift detection without synchronization requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If baseband generators and local oscillators are used for up conversion and down conversion, then RF signal transmission and reception can be achieved, but device complexity and cost increase
Solution Approach 1:
The patent extracts and eliminates the baseband generator and local oscillator components from the traditional RF transmission system. By using a DAC that can directly output RF frequencies, the system removes the need for separate upconversion stages, thereby reducing device complexity while maintaining RF signal transmission capability
Solution Approach 2:
The DAC is designed to perform multiple functions: it can generate RF signals directly for transmission and also generate the reference signals needed for downconversion during reception. This multi-functionality replaces what would traditionally require separate dedicated components for upconversion and downconversion operations
2Reliability
If baseband generators and local oscillators are used for up conversion and down conversion, then RF signal transmission and reception can be achieved, but cost increases
Solution Approach 1:
By removing the expensive baseband generator and local oscillator components, the system reduces overall manufacturing cost. The single DAC component is less costly than multiple dedicated RF generation components, and its direct RF output capability eliminates the need for additional upconversion hardware
Solution Approach 2:
The patent merges the functions of signal generation, upconversion, and reference signal generation into a single DAC component. This consolidation reduces the total component count and manufacturing complexity compared to having separate baseband generators and local oscillators
3Reliability
If local oscillators are used for up conversion and down conversion, then heterodyning can be performed, but phase synchronization issues arise
Solution Approach 1:
The patent removes the local oscillators that cause phase synchronization problems. By using a DAC with direct RF output capability, the system eliminates the need for oscillator phase matching between transmit and receive paths, thereby resolving phase synchronization issues
Solution Approach 2:
The system uses a copy of the transmitted RF signal (generated by the same DAC) as the reference for downconversion. This copied signal inherently maintains the correct phase relationship without requiring complex phase synchronization mechanisms between separate oscillators
Data Source
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AI summary
Embodiments include techniques for transmitting and receiving radio frequency (RF) signals, where the techniques for generating, via a digital analog converter (DAC), a frequency signal, and filtering the frequency signal to produce a first filtered signal and a second filtered signal. The techniques also include transmitting the second filtered signal to a device under test, and filtering the second filtered signal into a sub-signal having one or more components. The techniques include mixing the first filtered signal with the sub-signal to produce a first mixed signal, subsequently mixing the first mixed signal with an output signal received from the device under test to produce a second mixed signal, and converting the second mixed signal for analysis.