We study the effect of retardation of gravity in binary pulsars. It appears in pulsar timing formula as a periodic excess time delay to the Shapiro effect. The retardation of gravity effect can be large enough for observation in binary pulsars with the nearly edgewise orbits and relatively large ratio of the projected semimajor axis, x, to the orbital period of the pulsar, Pb. If one succeeds i...

vational facts, and then in another column compare them with the results of the theoretical program we have been carrying out at Chicago over the past few years. The purpose of this comparison will be to suggest experiments, some of which are already in progress, and which will perhaps resolve a few of the difficulties in our present knowledge of the dynamics of the interplanetary medium. I sha...

A spaceborne radar for atmospheric observation must be able to detect atmospheric backscatter in the presence of clutter due to antenna sidelobes. Here, we analyze the problem in detail, deriving a method for computing clutter which includes effects of all contributing transmit pulses, Doppler shifting, finite receiver bandwidth, and curved earth's surface. The results are applied to analysis o...

In this letter, the performance is compared for slowfrequency-hop and direct-sequence spread-spectrum packet communication systems of similar complexity with doubly selective fading channels characterized by several different multipath delay profiles and Doppler spreads. The delay profiles are chosen to reflect experimental measurements of mobile-radio channels, and the Doppler spreads are chos...

A compact cold-atom clock based on coherent population trapping is being developed. The clock aims to ultimately achieve a timing uncertainty of a few nanoseconds per day. Here we present an initial evaluation of the three main systematic frequency shifts – the first-order Doppler shift, the light shift, and the Zeeman shift. Planned steps to reduce the size of these shifts will also be presented.

The action of the Doppler effect on the particularities of radiation power spectral distribution of an electron moving in a spiral in a medium has been investigated near the Cherenkov threshold. The fine structure of the electromagnetic radiation spectrum at the Cherenkov threshold and the synchrotron-Cherenkov radiation spectrum for an electron moving along a spiral with non-relativistic longi...

For the jet pointing towards us: the spectrum in the jet rest frame is a power law from ν1 to ν2. In the observer frame, every frequency gets Doppler shifted by D+ = γ(1 + β cos θ) > 0, where β = v/c > 0 (RL equation 4.12b). The factor of 1 + β cos θ is the usual Doppler shift (train-whistle effect), while the factor of γ arises from time dilation. So the whole forward jet spectrum shifts to hi...

We present multiepoch VLBA observations of the compact jet of GRS 1915+105 conducted at 15.0 and 8.4 GHz during a plateau state of the source in 2003 March-April. These observations show that the compact jet is clearly asymmetric. Assuming an intrinsically symmetric continuous jet flow, using Doppler boosting arguments and an angle to the line of sight of θ = 70 • , we obtain values for the vel...

The performance of a wireless signal propagation can be estimated with the properties or characteristics of the channel. This paper begins with the classification of the important characteristic of a channel i.e, fading. After that fast fading modeling for multipath with no direct path and multipath with direct path is analyzed in the fourth part of this paper. In the last section of this paper...

This paper is to present a defect detecting and locating method of tubular cylindrical conductor based on alternating current impedance measurement theory. A defect estimation can be made through the impedance measurement of some distance on the inner and the outer surfaces of the tubular cylindrical conductor. A defect in the thickness direction can be located by the skin effect influence on i...