Browsing by Author "Castillo, O."
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Item Open Access La ingeniería electrónica en el Radio Observatorio de Jicamarca(Instituto Geofísico del Perú, 2009) Chau Chong Shing, Jorge Luis; Woodman Pollitt, Ronald Francisco; Castillo, O.; Yanque, R.Diapositivas presentadas en la conferencia "La Ingeniería Electrónica y el mundo Empresarial", realizado en la PUCP el 28 de mayo de 2009.Item Open Access Modos de observación en el espacio cercano con el radar de Jicamarca(Instituto Geofísico del Perú, 2010) Kuyeng, K.; Castillo, O.; Condori, L.; Chau Chong Shing, Jorge LuisEl Radio Observatorio de Jicamarca (ROJ) es la principal estación ecuatorial de la cadena de radio observatorios de dispersión incoherente (cuyas siglas en inglés es ISR) del hemisferio oeste que se extienden desde Lima - Perú hasta Søndre Strømfjord, Groelandia y la más importante en el mundo para estudiar la ionósfera ecuatorial. Esta compuesto de tres transmisores de 1.5 MW y un arreglo de antenas de 18,432 dipolos, cubriendo un área aproximada de 85,000 m2. El estudio de la ionósfera ecuatorial ha adquirido mayor importancia debido, en gran parte,a las contribuciones hechas por el Radio Observatorio de Jicamarca. El Observatorio se ubica a media hora de viaje en automóvil hacía el este de Lima y a 10 kms de la Carretera Central (latitud 11.95°Sur, longitud 76.87° Oeste).Item Open Access Shortest-pulses measurements with the SOUSY VHF radar at Jicamarca(Instituto Geofísico del Perú, 2006) Woodman Pollitt, Ronald Francisco; Michhue, G.; Castillo, O.; Roettger, J.We describe here the technical preparations for this special experiment, namely the careful measurements of the bandwidth of the antenna array, the transmitter and the receiver system. Test experiments were carried out with a complementary code with 250 nanoseconds band length. The transmitter stages were tuned for optimum amplitude and phase response. The signals at the output directional coupler and the received backscattered signals were oversampled at 125 nanoseconds, corresponding to 18.75 meter range. Due to the wide bandwidth of 6 MHz interference by the Channel-2 TV transmitter in Lima had to be minimized. The most resolution limiting factor is the bandwidth of the transmitter 600-kW final amplifier, which resulted in a minimum transmitted pulse width of 370 nanoseconds. Using the driver at 20 kW, the mínimum pulse width was even shorter. We describe the decoding and deconvolution procedures, which should allow a better resolution than 370 nanoseconds, as well as a local normalization method applied to the data. This shows that layers/sheets thinner than 30-40 meters were observed, which are described in paper 1.1. We claim that this configuration of the SOUSY VHF Radar at Jicamarca is the world-leading MST radar in terms of range resolution.Item Open Access Sousy radar at Jicamarca system description(Instituto Geofísico del Perú, Radio Observatorio de Jicamarca, 2003) Woodman Pollitt, Ronald Francisco; Castillo, O.; Michhue, G.; Reyes, P.; Villegas, S.The main characteristics that differentiate the SOUSY radar from the Jicamarca radar are: (1) its bandwidth (4 MHz against 700 KHz for the Jicamarca radar) and (2) its steerability. The wider bandwidth allows an altitude resolution of at least 75 meters. The Sousy radar is a phased array that allows for a wide and agile steerability of its antenna (+/- 15°). In order to satisfy our scientific need, we have redesigned the antenna to have two main positions, zenithal and 15° south.Item Open Access The CALOR project at Jicamarca: initial steps. Controlled upper atmosphere experiments with a LOwband radar(Instituto Geofísico del Perú, 2010-03-30) Chau Chong Shing, Jorge Luis; Hysell, D. L.; Castillo, O.; González, S. A.Diapositivas de una presentación oral realizada en Arecibo, Puerto Rico, en el año 2010.Item Open Access The MPI-SOUSY-VHF Radar at Jicamarca: high altitude-resolution capabilities(Instituto Geofísico del Perú, 2007) Woodman Pollitt, Ronald Francisco; Michhue, G.; Röttger, J.; Castillo, O.The MPI-SOUSY radar has been moved from its original location at the Harz Mountains, Germany, to the Jicamarca Observatory. Two main modifications have been made to the system: 1) The antenna array now consist of 126 Yagis deployed in an square array of 16x16, 4 element Yagis, similar to the original ones, and 2) the control and data acquisition system has been modernized as described later on. The phase steering system has not been implemented yet, but is planned for the future.Item Open Access The on-axis beam at Jicamarca: is it pointing correctly?(Instituto Geofísico del Perú, 1995) Chau Chong Shing, Jorge Luis; Balsley, B.B.; Huamán, M.M.; Castillo, O.; Woodman Pollitt, Ronald FranciscoVertical velocity measurements of atmospheric winds are becoming increasingly important. To obtain the long-term mean vertical motion of the atmosphere is difficult to do, both because of the small velocities involved and because of the finite width of the antenna beam. Since the vertical wind measurement is very sensitive to the tilt of the vertically-directed antenna beam, we decided to get the Jicamarca beam direction by measuring the phase and amplitude of a reference signal at each of the antenna feed points. Our results tell us that, while the antenna pointing direction is already good, there is room for improvement.