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Seasonal variability of vertical eddy diffusivity in the middle atmosphere: 1. Three‐year observations by the middle and upper atmosphere radar
The vertical eddy diffusivity K due to atmospheric turbulence with spatial scales of 100–102 m has been computed from the echo power spectral width observed by the middle and upper atmosphere radarExpand
Mid‐latitude E region field‐aligned irregularities observed with the MU radar
Fine structures E region field-aligned irregularities were observed on June 24–25, 1989, with the MU radar at Shigaraki, Japan (34.9°N, 136.1°E; geomagnetic latitude 25.0°N). The 3.2-m scaleExpand
Equatorial Atmosphere Radar (EAR): System description and first results
[1] A VHF Doppler radar with an active phased-array antenna system, called the Equatorial Atmosphere Radar (EAR), was established recently at the equator near Bukittinggi, West Sumatra, IndonesiaExpand
Phase reversal of the diurnal cycle in the midlatitude ionosphere
[1] The typical diurnal cycle of the midlatitude F region electron density consists of a midday maximum and a midnight minimum. However, a phase reversal of this diurnal cycle has been found to occurExpand
The SEEK (Sporadic‐E Experiment over Kyushu) Campaign
The SEEK (Sporadic-E Experiment over Kyushu) campaign was conducted in late August 1996 from the southern region of Kyushu, Japan, to investigate the mechanism for the generation of quasi-periodicExpand
Gravity wave modulation of gradient drift instabilities in mid-latitude sporadic E irregularities
Recent E region VHF backscatter echoes observed by the MU radar at mid-latitudes show quasi-periodic striations with a fairly constant range vs. time tilt in a RTI display. These features areExpand
Gravity waves in the mesosphere observed with the middle and upper atmosphere radar
We have observed wind motions from 60 to 90 km altitudes with the middle and upper atmosphere (MU) radar during daylight hours (0800–1600 LT) from October 13 to 31, 1986. Gravity waves with fairlyExpand
Seasonal variation of momentum flux in the mesosphere observed with the MU radar
We have regularly monitored mesospheric winds at 60–85km for three years with the MU radar (35°N, 136°E), and have found that the variance of wind velocity fluctuations for periods from 5 min to 2 hrExpand
Estimation error of spectral parameters of mesosphere-stratosphere-troposphere radars obtained by least squares fitting method and its lower bound
We have calculated the estimation error of parameters of echo power spectra observed by mesosphere-stratosphere-troposphere (MST) radars by means of computer simulations for least squares fitting andExpand
Description and demonstration of the new Middle and Upper atmosphere Radar imaging system: 1‐D, 2‐D, and 3‐D imaging of troposphere and stratosphere
[1] The Middle and Upper atmosphere Radar (MUR) was upgraded in March 2004 for radar imaging capability with 5 frequencies across a 1 MHz bandwidth and 25 digital receivers. Although digitizationExpand