Patent ID: 8683859

Claim:
Apparatus to provide monitoring of pressure outside the wellbore casing of a well, said apparatus comprising: a Wireless Sensor Unit (â€œWSUâ€) placed outside a section of a non-magnetic casing, said WSU including a sensor device to measure the pressure and/or the temperature of its surroundings, wherein the WSU may be installed or positioned at any elevation of a wellbore and wherein the WSU is powered by Power Harvesting where the frequency of an induction signal is in the range of 10-1000 Hz for deep penetration through the non-magnetic casing; and an internal Sensor Energizer Unit (â€œSEUâ€) for placement inside the wellbore casing, said SEU being used to provide power to and communication with the WSU, wherein the SEU is attached to the well production tubing on a process tubing segment having a thread that allows adjustment of said SEU's elevation, and wherein the SEU converts DC power supplied by a cable from the surface to an alternating electromagnetic field that provides a source of power for the WSU outside the wellbore casing; wherein the SEU and the WSU use an electromagnetic modulation technique to provide communication of data therebetween.