OFDM stands for **o**rthogonal, **f**requency-**d**ivision **m**ultiplexing.
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using different pulse shapings in ofdm [closed]
Hi I have simulated and ofdm system with rectangular pulse but I have prolems how to simulate it with other pulse shapings. could any one help, please? I want to compare the bit error rate for ...
2
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1answer
73 views
OFDM training symbol format
For OFDM synchronisation, we are using two training symbols according to the Schmidl and Cox method of frequency synchronization and timing synchronization. The paper says:
The first OFDM training ...
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2answers
82 views
Need for Oversampling in OFDM and symbol time determination
I am trying to implement OFDM on gnuradio. I have two questions.
The sampling frequency which is slightly higher than available bandwidth satisfies Nyqvist criterion for complex baseband signals. ...
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85 views
Ricean Multipath channel model implementation
I'm trying to implement a multipath ricean channel model. I had found several resources but I'm kind of lost with too much information. What I have from now is the following step:
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1answer
52 views
Windowing a time domain OFDM signal
Windowing is a popular method of reducing the spectral sidelobes of OFDM. A popular window usually used for this purpose in the raised cosine (RC) window, because of its tapered and smooth edges. I ...
2
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3answers
92 views
OFDM coarse freq estimation
I am trying to read OFDM synchronization paper by Schmidl and Cox. The math is slightly overwhelming.
What is the formula that they use in implementation that distinguishes between coarse estimation ...
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1answer
88 views
Determining sampling rate in OFDM demodulation
I have seen that in OFDM, the sampling rate is much lesser than twice the bandwidth of signal. why is it so? How is sampling rate calculated in OFDM? Does it depend on the modulation type used inside ...
3
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2answers
76 views
Fixed point channel model for OFDM system
I'm testing an OFDM system implemented in fixed point. The data format is Q11. My system work's fine but I need to test it under some channel for evaluation of the design before field testing. The ...
2
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1answer
167 views
Apply AWGN noise to QPSK-OFDM symbol
I'm working on an OFDM-QPSK based system and I'm having some trouble to match the BER of my system with the theoretical curve. My OFDM implementation fills all the subcarriers and have t_symbol s ...
2
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1answer
126 views
Spectrum of OFDM with raised cosine window
I'm having trouble implementing OFDM with a raised cosine (RC) window in Matlab. I know how to generate an OFDM signal and how to show its spectrum, I just don't know how to generate the window ...
2
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1answer
174 views
Why does OFDM use cyclic-prefix while QPSK uses root-raised cosine filters?
My understanding is that BPSK/QPSK/... are often implemented with root-raised cosine (RRC) filters to reduce ISI and bandwidth.
OFDM can be understood to be BPSK/QPSK/... implemented on multiple ...
3
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4answers
311 views
How is symbol synchronization with OFDM done?
I'm trying to understand how symbol synchronization is done in OFDM using pilot tones, cyclic prefixes, or any other technique.
I've read the following answers which provide some explanation, but I ...
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3answers
583 views
IFFT Concept in OFDM
can any one explain how actually IFFT generating sub carriers in OFDM.... when we are simulating OFDM transmitter in matlab, we are taking input data stream, encoding it and modulating the encoded ...
0
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1answer
197 views
OFDM transmitter data rate
i am simulating OFDM transmitter in matlab....As u all know OFDM consists of different sub systems such as FEC coding, Bit interlever , Modulator , IFFT block and Adding cyclic prefix.... i have ...
2
votes
1answer
246 views
Half Subcarrier spacing in LTE Uplink
First post here, trying to make it as good as possible. Do not know how to make the Python code look nice - any tips? :) Anywho - to the main problem:
I am currently working on simulating the uplink ...
3
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2answers
773 views
what's the baseband FFT size of LTE?
In standard of 3GPP LTE physical layer(3GPP TS 36.211), the FFT size for baseband signal generation for both Dl and UL is 2048 and CP size is also determined. However there is a table in several ...
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1k views
How to demodulate an OFDM signal
I'm looking at decoding an OFDM signal which consists of 6 carriers (or tones) which are BPSK modulated and a pilot tone which aids tuning. This is the first time I have worked with OFDM so I need to ...
