Modelling and observation of transionospheric propagation results from ISIS II in preparation for ePOP

Gillies, R. G.; Hussey, G. C.; James, H. G.; Sofko, G. J.; André, D.

doi:10.5194/angeo-25-87-2007

Cited by 11 publications

(22 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is also possible that if the transmitted pulse length is too short, or the mode delay difference is too long, the O and X mode portions of a pulse may be completely separated when they arrive at the RRI. Mode delay difference observations by the ISIS II satellite of an HF ground transmitter has been reported by James [2006], James et al [2006], and Gillies et al [2007].…”

Section: Hf Propagation Modelingmentioning

confidence: 94%

“…In a magnetoionic medium the polarization ratios of the two modes of propagation are [ Budden , 1961]:

ρ = i \frac{{false(Y normals normali normaln θ false)}^{2}}{2 Y c o s θ (1 - X - i Z)} \pm i \sqrt{\frac{{false(Y normals normali normaln θ false)}^{4}}{4 {(Y c o s θ)}^{2} {(1 - X - i Z)}^{2}} + 1} .

Under quiet conditions ( K P < 2 or 3), it is expected that collisions in the D and lower E regions will not have a significant effect on the transmitted signal. For disturbed conditions (3 < K P < 5), there may be ∼2–4 dB of signal absorption between the SuperDARN transmitter and the satellite in orbit [e.g., James et al , 2006; Gillies et al , 2007]. Under more disturbed conditions ( K P > 5) collisions may have a significant effect on the transionospheric signal (for example, the X mode may be completely absorbed in the E region); however, the models presented in this study consider only quiet and well‐behaved ionospheric conditions.…”

Section: Hf Propagation Modelingmentioning

confidence: 99%

“…For example, the effects of large‐scale ionospheric structures (∼500 km) on signal parameters such as power, delay, and arrival direction have been modeled by Wang et al [2004]. Analysis of similar transionospheric HF signals received by the ISIS satellites from a transmitter located in Ottawa, Canada in 1978 was undertaken by James [2006], James et al [2006] and Gillies et al [2007]. These studies compared features observed at the ISIS II satellite to the same parameters determined using computational models.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Modeling measurements of ionospheric density structures using the polarization of high‐frequency waves detected by the Radio Receiver Instrument on the enhanced Polar Outflow Probe

et al. 2012

Self Cite

View full text Add to dashboard Cite

The Cascade SmallSat and Ionospheric Polar Explorer (CASSIOPE) satellite is to be launched in late 2012. On board this satellite will be a suite of eight scientific instruments composing the enhanced Polar Outflow Probe (ePOP). The Radio Receiver Instrument (RRI) on ePOP will be used to receive high‐frequency (HF) (10–18 MHz) transmissions from ground transmitters such as the Super Dual Auroral Radar Network (SuperDARN) array. Modeling of the characteristics of the HF signal received at ePOP for various ionospheric conditions has been undertaken in preparation for this RRI‐SuperDARN experiment. The effect of ionospheric electron density enhancements and depletions on signal parameters such as polarization and mode delay difference has been modeled. It has been found that at HF the polarization state of the received signal is highly sensitive to regions of locally enhanced or depleted electron density in the ionosphere. In particular, analysis of the orientation angle of the received signal, which changes because of Faraday rotation as the spacecraft passes over a ground transmitter, will allow detection of small‐scale electron density structures (on the order of tens of kilometers) with electron densities as little as 10% different from background values. Because of the sensitivity of the polarization of HF transionospheric waves, the signatures of these small‐scale and relatively weak ionospheric density structures will be apparent. Larger and denser structures will also be detectable from both the polarization state and other signal parameters, such as signal delay. The modeling demonstrates that detailed analysis of the signal parameters received at the ePOP satellite will allow determination of the location, size, and density of structures in the ionosphere.

show abstract

Section: Hf Propagation Modelingmentioning

confidence: 94%

“…In a magnetoionic medium the polarization ratios of the two modes of propagation are [ Budden , 1961]:

ρ = i \frac{{false(Y normals normali normaln θ false)}^{2}}{2 Y c o s θ (1 - X - i Z)} \pm i \sqrt{\frac{{false(Y normals normali normaln θ false)}^{4}}{4 {(Y c o s θ)}^{2} {(1 - X - i Z)}^{2}} + 1} .

Section: Hf Propagation Modelingmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Modeling measurements of ionospheric density structures using the polarization of high‐frequency waves detected by the Radio Receiver Instrument on the enhanced Polar Outflow Probe

et al. 2012

Self Cite

View full text Add to dashboard Cite

show abstract

“…For quiet conditions (K p < 2 or 3), it is expected that the amount of absorption for either mode at SuperDARN frequencies will be less than 1 dB. For slightly disturbed conditions (3 < K p < 5), the absorption will be no more than ∼2 dB for the O-mode and ∼4 dB for the X-mode Gillies et al, 2007). Finally, for very disturbed conditions (K p > 5 or 6), both modes will be almost completely absorbed in the D-and E-regions and no signal will reach the RRI receiver.…”

Section: Cutoff Elevation Anglesmentioning

confidence: 99%

“…For example, Wang et al (2003) studied the signature of ionospheric structures on the received power, signal delay, and direction of arrival. Thorough studies of data and modelling from a previous HF transionospheric experiment performed by the ISIS II satellite have also been performed by James (2006), James et al (2006), Gillies (2006), and Gillies et al (2007). In these studies, the experimentally measured Faraday rotation and differential signal delay of radio waves was compared to the same parameters as determined by computational models.…”

Section: Introductionmentioning

confidence: 99%

Relative O- and X-mode transmitted power from SuperDARN as it relates to the RRI instrument on ePOP

et al. 2010

Self Cite

View full text Add to dashboard Cite

Abstract. The Cascade Demonstrator Small-Sat and Ionospheric Polar Explorer (CASSIOPE) satellite is scheduled to be launched in 2010. On board this satellite will be a suite of eight scientific instruments comprising the enhanced Polar Outflow Probe (ePOP). One instrument is the Radio Receiver Instrument (RRI) which will be used to receive HF transmissions from various ground transmitters such as the Super Dual Auroral Radar Network (SuperDARN) array. Magnetoionic polarization and propagation theory have been used to model the relative power that SuperDARN delivers to the Ordinary (O) and Extraordinary (X) modes of propagation. These calculations have been performed for various frequencies in the SuperDARN transmitting band and for all five Canadian based SuperDARN radars. The geometry of the radars with respect to the background magnetic field results in the X-mode dominating the transmitted signal when the modelled wave propagates northward and is nearly perpendicular to the magnetic field lines. Other propagation directions (i.e., above or southwards of the radar) results in propagation which is anti-parallel to the magnetic field lines and an equal splitting of transmitted power between the O-and X-modes occurs. The modelling analysis shows that for either high transmitting frequencies or low ionospheric electron densities, the range of latitudes that signal will be received is quite large (up to ∼90 • of latitude). Also for these conditions, the range of elevations where the X-mode signal strongly dominates the O-mode signal will be apparent in the received signal. Conversely, for lower transmitting frequencies or higher ionospheric electron densities, the latitudinal range that signal will be received over is smaller. Here the X-mode-only band is not apparent in the received signal as both modes will be received with roughly equal power. These relative mode power calculations can be used to characterize Correspondence to: R. G. Gillies (rob.gillies@usask.ca) the average electron density content in the ionosphere or provide a measure of relative absorption in the D-and E-regions when the satellite passes through the field-of-view of a SuperDARN radar.

show abstract

Ionospheric tomography using ADS-B signals

Cushley

Noël

2014

Radio Sci.

View full text Add to dashboard Cite

Numerical modeling has demonstrated that Automatic Dependent Surveillance Broadcast (ADS-B) signals can be used to reconstruct two-dimensional (2-D) electron density maps of the ionosphere using techniques for computerized tomography. Ray tracing techniques were used to determine the characteristics of individual waves, including the wave path and the state of polarization at the satellite receiver. The modeled Faraday rotation was computed and converted to total electron content (TEC) along the raypaths. The resulting TEC was used as input for computerized ionospheric tomography (CIT) using algebraic reconstruction technique. This study concentrated on reconstructing mesoscale structures 25-100 km in horizontal extent. The primary scientific interest of this study was to show that ADS-B signals can be used as a new source of data for CIT to image the ionosphere and to obtain a better understanding of magneto-ionic wave propagation.

show abstract

Modelling and observation of transionospheric propagation results from ISIS II in preparation for ePOP

Cited by 11 publications

References 15 publications

Modeling measurements of ionospheric density structures using the polarization of high‐frequency waves detected by the Radio Receiver Instrument on the enhanced Polar Outflow Probe

Modeling measurements of ionospheric density structures using the polarization of high‐frequency waves detected by the Radio Receiver Instrument on the enhanced Polar Outflow Probe

Relative O- and X-mode transmitted power from SuperDARN as it relates to the RRI instrument on ePOP

Ionospheric tomography using ADS-B signals

Contact Info

Product

Resources

About