Abstract: An ion source for use in a radiation generator tube includes a back passive cathode electrode, a passive anode electrode downstream of the back passive cathode electrode, a magnet adjacent the passive anode electrode, and a front passive cathode electrode downstream of the passive anode electrode. The front passive cathode electrode and the back passive cathode electrode define an ionization region therebetween. At least one Spindt cathode is configured to emit electrons into the ionization region. The back passive electrode electrode and the passive anode electrode, and the front passive cathode electrode and the passive anode electrode, have respective voltage differences therebetween, and the magnet generates a magnetic field, such that a Penning-type trap is produced to confine the electrons to the ionization region. At least some of the electrons in the ionization region interact with an ionizable gas to create ions.

Abstract: Systems and methods cancel or compensate for an echo or noise in borehole communication. The systems and methods provide a downhole tool configured to provide borehole communication via mud pulse telemetry. The downhole tool pulses drilling fluid to generate a first pressure pulse and a second pressure pulse. The first pressure pulse moves upwardly with respect to the downhole component and is encoded with data associated a downhole measurement. A sensor is electrically connected to and in communication with the downhole tool. The first sensor is adapted to detect a characteristic of the second pressure pulse in the drilling mud. A ideal pressure pulse or a correction pressure pulse is generated by a downhole tool or a mud pulse modulator to reduce or cancel noise of the second pressure pulse.

Abstract: Systems and methods cancel or compensate for an echo or noise in borehole communication. The systems and methods provide a downhole tool configured to provide borehole communication via mud pulse telemetry. The downhole tool pulses drilling fluid to generate a first pressure pulse and a second pressure pulse. The first pressure pulse moves upwardly with respect to the downhole component and is encoded with data associated a downhole measurement. A sensor is electrically connected to and in communication with the downhole tool. The first sensor is adapted to detect a characteristic of the second pressure pulse in the drilling mud. A ideal pressure pulse or a correction pressure pulse is generated by a downhole tool or a mud pulse modulator to reduce or cancel noise of the second pressure pulse.