How Cross domain signal analysis in LTE
Regarding cross domain analysis, we see that, I traditionally signal from a receiver RF section can be demodulated and Q components using analog techniques. Today, however, the down conversion signal is digitized by an ADC IF, and usually then fed into the section of the baseband demodulation and decoding.
In Cross domain signal Measurement ADC output is a challenge because production is now in the digital domain. A solution is to analyze the digital bits from the ADC directly using a logic analyzer for capturing digital data. The hard part of this solution is data processing in a significant result because most applications of logical analysis does not focus on RF metric generation. Using Agilent 89601A software vector signal analysis (VSA) is a way to solve this challenge.
VSA software can run on a number of Agilent spectrum analyzers for Cross domain signal analysis, oscilloscopes and logic analyzers for demodulating various modulation formats, and offers a unique way to analyze the ADC performance by being able to make traditional RF measurements directly into digital data. This approach gives a designer the ability to quantify the ADC contribution to the overall system performance and RF measurements compared to using the same measurement algorithms.
If IQ RFIC has analog outputs, can be analyzed by an Agilent oscilloscope or MXA signal analyzer. If RFIC uses DigRFv3 or v4 interface, the signal can be captured by (RDX) Radio Tester Digital Domain.
These analog or digital IQ signals can be analyzed with the same software 89601A VSA for Cross domain signal analysis in LTE. For developer tape hardware probes are available for analog and IQ DigRF interface. VSA software provides EVM performance measurements for verification numerical and graphic details additional useful during product development to isolate the source of signal impairments. If Gaussian noise added to the signal deterioration, a relationship can be drawn between EVM and BER cruel. Alternatively, the signals captured IC can be placed in a simulated Agilent receiver and software design for LTE. The precise design of the receiver determines the performance, so that the results can vary depending on the specific application provider.