First‐light measurements from the Canadian face of the Resolute Bay Incoherent Scatter Radar (RISR‐C) were taken in August of 2015. Data were taken for roughly 25 h on both RISR‐C and the North face of the Resolute Bay radar (RISR‐N) in an 11‐beam World Day mode. Overall, the measurements from the RISR‐C radar are of high quality and consistent with results from the RISR‐N radar. During the 25 h period analyzed in this study, the ionosphere responded to changes in orientation of the interplanetary magnetic field . During one particular event, a change from Bz negative to positive and By positive to negative caused the antisunward flow to stall, and a strong dawn‐to‐dusk flow, with decreased electron density and increased ion temperature, replaced it in the RISR‐C field of view. Overall, it is clear that measurements from the RISR‐C radar will complement and greatly expand the scope of ionospheric polar cap measurements.

Abstract. We present first results from a search for quasi-periodic (QP) radar echoes in the American sector. These echoes, which are produced by underdense backscatter from field-aligned irregularities in nighttime midlatitude sporadic E (Es), have been observed in the Asian sector but never before at other longitudes.Using radar data collected during the summer in 1998 from Stanford, California, we show that QP echoes can indeed be detected in the American sector and that they resemble those found in central and southern Japan. We then show that the invariance of a feature in the pattern of QP echoes, which persisted for five hours on 3 August 1998, raises questions regarding the existing models for QP echoes.

�bstract-AMISR is a modular� mobile� UHF radar facility used by scientists and students from around the world to conduct studies of the upper atmosphere and to observe space weather events. SRI International� under a grant from the National Science Foundation� is leading the collaborative effort in the development and operation of AMISR. The novel modular configuration allows for relocating the radar to study upper atmospheric activity at different locations around the globe. Remote operation and electronic beam steering allow researchers to operate and position the radar beam on a pulse-to-pulse basis to accurately measure and glean new information from rapidly changing space weather events.

[1] The Radio Aurora Explorer CubeSat detected the first radar echoes during the solar storm of March 8, 2012. The 300 s ground-to-space bi-static radar experiment was conducted in conjunction with the Poker Flat Incoherent Scatter Radar in the local morning ($8 am) over Poker Flat, Alaska. The geomagnetic conditions for the E region field-aligned irregularity generation were optimal due to strong (about 1500 m/s) F region ion drifts and sufficient E region ionization (electron densities were $2 Â 10 11 m À3 ). The corresponding E region electric field of $80 mV/m was larger than the excitation threshold for the Farley-Buneman instability. An auto-correlation analysis resolved, for the first time, the distribution of auroral E region backscatter with 3 km resolution in altitude and sub-degree resolution in aspect angle. Moreover, the measured Doppler velocities of the UHF scatter shows the phase speed saturation of the meter-scale plasma waves. The measured Doppler velocity is in excellent agreement with the C s cos q formula for auroral E region irregularities. Citation: Bahcivan, H., J.

We introduce a new kind of diagnostic sensor that combines multifunctional measurement capabilities for ionospheric research. Multifunctionality is realized through agility in frequency selection over an extended band (1.5 to 50 MHz), system modularity, complete system control by software written in C, and a user‐friendly computer interface. This sensor, which we call the frequency‐agile radar (FAR), incorporates dual radar channels and an arbitrary waveform synthesizer that allows creative design of sophisticated waveforms as a means of increasing its sensitivity to weak signals while minimizing loss in radar resolution. The sensitivity of the FAR is determined by two sets of power amplifier modules: four 4‐kW solid‐state broadband amplifiers, and four 30‐kW vacuum tube amplifiers. FAR control is by an AT‐bus personal computer with on‐line processing by a programmable array processor. The FAR does not simply house the separate functions of most radio sensors in use today, it provides convenient and flexible access to those functions as elements to be used in any combination. Some of the first new results obtained with the FAR during recent field campaigns are presented to illustrate its versatility. These include (1) the first detection of anomalous high‐frequency (HF) reflections from a barium ion cloud, (2) the first evidence of unexpectedly large drifts and a shear north of the equatorial electrojet, (3) the first HF radar signature of a developing equatorial plasma bubble, and (4) the first measurements by a portable radar of altitude‐extended, quasi‐periodic backscatter from midlatitude sporadic E. We also mention the potential of the FAR for atmospheric remote sensing.