Range Imaging of E-Region Field-Aligned Irregularities by Using a Multifrequency Technique: Validation and Initial Results

Correct of the caption for figure 4

“…To further confirm the comparison results, we have examined more echoes with the same atmospheric conditions and two of them are shown in the right two columns. As seen in the cases of atmospheric echoes shown in panel (c), V RIM was in agreement with V STD150 , consistent with the study made by Chilson (2004). Similarly, V RIM and V STD150 of the precipitation were consistent with each other, as observed in panel (e).…”

“…According to Chilson (2004), by giving s n (t) as the column vector of temporal signals for N carrier-frequency pulses where n = 1, . .…”

“…To validate the time-signal inversion approach, we have executed examinations similar to those made by Chilson (2004). Figure 5 illustrates an example in which precipitation and atmospheric echoes coexisted.…”

“…The frequency-hopped technique with several frequencies, commonly referred to as range imaging (RIM;Palmer et al, 1999) or frequency domain radar interferometric imaging (FII; Luce et al, 2001), has been useful for remote sensing of the atmosphere. Further investigations of the RIM technique and its applications have been made by many researchers (Luce et al, 2007(Luce et al, , 2010Chen et al, 2016a, b;Chilson et al, 2001;Chilson, 2004;Yu et al, 2010, and the references therein). Among numerous previous studies of RIM , Chilson et al (2001) and Luce et al (2007) compared the generalized refractive index profiles estimated from radiosonde data and the echo power (brightness distribution) retrieved from the RIM, and demonstrated that the vertical structures in the troposphere identified by the RIM technique were natural phenomena and not artificial results.…”

“…Among numerous previous studies of RIM , Chilson et al (2001) and Luce et al (2007) compared the generalized refractive index profiles estimated from radiosonde data and the echo power (brightness distribution) retrieved from the RIM, and demonstrated that the vertical structures in the troposphere identified by the RIM technique were natural phenomena and not artificial results. In a later study, Chilson (2004) applied time-signal inversion process to the RIM data to obtain temporal signals in sub-gates and executed the spectral analysis for each sub-gate, giving high-resolution spectra of the atmospheric echoes in the range direction. To improve the continuity of the brightness distribution through the range gate boundaries, developed a calibration process for the RIM, and in a later study Chen et al (2016a) proposed further a procedure of point-by-point calibration for the RIM analysis of precipitation echoes in the time domain.…”