Questions tagged [modulation]
8 questions
8
votes
1 answer
Why does the LTE Specification define SC-FDMA as the modulation scheme for the reverse link?
The LTE specification specifies SC-FDMA as the encoding scheme for the reverse link (mobile to base station) when the forward link uses OFDMA.
What is the reason for the difference?
psubsee2003
- 189
- 7
3
votes
0 answers
What is PSS waveform formula?
I want to know how is exactly modulated a LTE subcarrier.
Since I'm working on Synchronization Signals (P-SS, S-SS) the subcarriers I'm talking about are centered around DC.
I have coded the algorithms that output diverse information (Zadoff-Chu…
Amesys
- 261
- 1
- 3
1
vote
2 answers
Demodulation of AM signals in radio broadcast systems
I have a question regarding the demodulation of AM signals in radio systems (like car radio).
I know that in order to send the audio signal from the broadcasting station to users we need first to AM modulate it with fc and s(t) will be the modulated…
Daniel Cohen
- 11
- 2
1
vote
1 answer
Difference between AD630 'Phase Comparator' and 'Lock-in Amplifier' modes
The datasheet of the AD630 mentions that the device can be used as a Precision Phase Comparator or as a Lock-in Amplifier.
What's the difference? They both seem to map the amplitude of a modulated signal to around DC. That is, the output of both…
Remco Poelstra
- 163
- 3
1
vote
1 answer
How the electronic circuit control laser diode?
I find this scheme here
1 - is data stream come from computer. This 'data' is an electric signal moudulated by the n°2
2 - this is the electronic circuit inside printer that
a) activates the corona wire → b) the corona wire charges up the…
user332153
- 65
- 4
1
vote
0 answers
What system-electronic components or physic mechanism is used to modulate signals between different devices used in lithography?
I know that pattern generator device (no pattern generator software) is needed to generate a model signal system that help you use electron diffraction for wafer surface printing by the use of the TEM. These signals are templates called patterns and…
Jacky Ned
- 23
- 3
0
votes
0 answers
Real-world CQI-to-MCS and SNR-to-CQI tables?
How can I get real-world CQI-to-MCS and SNR-to-CQI tables? I am particularly looking for 5G-NR or LTE-A related tables.
Can someone share any references?
Edit: I had found one table for CQI-MCS conversion here. But there are no details as to how…
SJa
- 101
- 1
0
votes
1 answer
How to turn a photo receptive sensor into an emitter of light?
I try to understand how is possible to turn a photo receptive sensor into an emitter of light.
Settings, tools, modulation..
Jacky Ned
- 23
- 3