July 1, 2016 at 3:22 pm #303
Thanks for the nice introduction to your simulator! I have got a gew questions to your simulations:
– What carrier frequency did you assume here? Statements about user speed without knowing the carrier frequency are not really instructive.
– Where does the slight discrepancy between the analytic behaviour over Rayleigh fading compared to your simulations come from (in the figure shown around 16:30)?
– Can you please explain what is the main cause for the performance degradation of BER versus speed (shown around 17:00).
Thanks.July 1, 2016 at 5:03 pm #304
Thank you for your question.
Regarding the first question, we used a frequency of 2.6 GHz for our simulations. However note that in this paper we just included some exemplary results. If you are interested in evaluations performed with our simulator you can check the references bellow.
Regarding the second question, the analytical curve is for an analytical flat fading Rayleigh channel (was obtained using the MATLAB “berfading” function). The curves for the simulations of that figure were obtained using the 3GPP Rural Area channel model (RAx), and also considering a mobility scenario, so the channel for that case is doubly selective. Hence, as the curves correspond to different channel models, results are not the same. Notice that the slope of the curve for the RAx channel model is approximately the same than the one for the flat Rayleigh channel, although the BER results are worse in the first case as the RAx channel model introduces more impairments on the signal.
Regarding the third question, BER increases with speed because higher speeds lead to higher ICI (intercarrier interference) values, and we are not considering any interference cancellation scheme at the receiver. Moreover, the pilot spacing needs to be low enough to not exceed the channel coherence time, which decreases for higher speeds.
Tomás Domínguez-Bolaño and José Rodríguez-Piñeiro.
Papers based on measurements:
J. Rodríguez-Piñeiro, T. Domínguez-Bolaño, J. A. García-Naya, L. Castedo, “Performance Assessment of 5G-Candidate Waveforms in High Speed Scenarios”. 27th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC 2016), Valencia, Spain, September 2016.
José Rodríguez-Piñeiro, Martin Lerch, Tomás Domínguez-Bolaño, José A. García-Naya, Sebastian Caban, Luis Castedo, “Experimental Assessment of 5G-Candidate Modulation Schemes at Extreme Speeds”, accepted at the Ninth IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM 2016), 10th-13th July 2016, Rio de Janeiro, Brazil.
Papers based on simulations:
J. Rodríguez-Piñeiro, T. Domínguez-Bolaño, P. Suárez-Casal, J. A. García-Naya, L. Castedo, “Affordable Evaluation of 5G Modulation Schemes in High Speed Train Scenarios”, Proceedings of the 20th International ITG Workshop on Smart Antennas (WSA 2016), Mar. 2016, Munich, Germany
T. Domínguez-Bolaño, J. Rodríguez-Piñeiro, J. A. García-Naya, and L. Castedo, “Experimental Evaluation of 5G Modulation Schemes in Quasi-Static Scenarios”, Proceedings of the 20th International ITG Workshop on Smart Antennas (WSA 2016), Mar. 2016, Munich, Germany
You must be logged in to reply to this topic.