El Aroudi, A.; Al-Numay, M.; Calvente, J.; Rodriguez, E.; Alarcon, E. International journal of electronics Vol. 103, num. 12, p. 2090-2109 DOI: 10.1080/00207217.2016.1178342 Data de publicació: 2016-12 Article en revista
New exact critical conditions for predicting subharmonic instability in switching regulators are approximated by simple design-oriented expressions valid under practical conditions. These simplified expressions contain the ripple and slope information of the feedback control signal. Depending on the converter topology, the controller used and values of parasitic parameters, either the slope or the ripple can be dominant in predicting instability. A discussion on the validity of this interpretation is illustrated through six different examples of switching regulators using the concept of the spectral radius and the relative degree of the system loop. Using this approach, the boundary between the desired stable region and the subharmonic instability can be easily obtained. The theoretical results are validated by means of numerical simulations.
Cosp, J.; Binczak, S.; Madrenas, J.; Ruiz Fernández, D. International journal of electronics Vol. 101, num. 2, p. 220-230 DOI: 10.1080/00207217.2013.780263 Data de publicació: 2014-02-01 Article en revista
Mon, J.; Gago, J.; Gonzalez, D.; Balcells, J.; Fernandez-Garcia, R.; Gil, I.; Bogonez, F. International journal of electronics Vol. 99, num. 1, p. 103-112 DOI: 10.1080/00207217.2011.610026 Data de publicació: 2012-01 Article en revista
Pons, M.; Martorell, F.; Aragones, X.; Moll, F.; Rubio, A. International journal of electronics Vol. 95, num. 3, p. 227-237 DOI: 10.1080/00207210701827921 Data de publicació: 2008-03-12 Article en revista
In the paper, an analytical model for ground bounce noise evaluation taking into account the interdependence between IDD switching current and VDD noise voltage is presented. The model shows the discrepancies from general accepted assumption of independence between the two variables. The main conclusion is that noise calculations using the independence assumption cause an overestimation of the noise levels. The results are verified through realistic simulations and for different technology nodes and accurate analysis of two canonical circuits.
Stationary lognormal random processes find application in radar and transmission systems as models of signal generators. This paper describes a simulation model for generating either complex or real-valued lognormal, wide-sense stationary, random processes. The basic model considers a nonlinear processing of a complex-valued gaussian random process. The accuracy of the model is assessed through the simulation of realistic test cases.
We present a parallel modem for 2400 b.p.s. data transmission over high-frequency (h.f.) ionospheric channels. Time-redundancy (convolutional coding) and frequency diversity (parallel transmission with pre-encoding) are used in order to combat the frequency-selective fading and the narrow-band interference commonly shown by these channels. In-band real-time channel evaluation (RTCE) techniques are used in order suitably to select the best sub-bands from the redundant set, and to form the originally transmitted data sequence. The modulation scheme chosen for the parallel carriers is QAM-16
High-frequency modem with multilevel parallel transmission using coding and RTCE (PDF Download Available). Available from: https://www.researchgate.net/publication/271559296_High-frequency_modem_with_multilevel_parallel_transmission_using_coding_and_RTCE [accessed Feb 23, 2016].