Abstract: There is described the use of Digital Radio Frequency Memory (DRFM) modules to jam certain communication signals while allowing others to be received on a given frequency band. The DRFM modules exploit the multi-path phenomenon by using transmitted signals to cause full band destructive echoes and/or distortions. A set of receivers used in conjunction with the DRFM modules are aware of the exact multi-path induced by the DRFM modules and are therefore able to mitigate or even benefit from the effects of the destructive multi-path and maintain or improve communications.

Abstract: There is described a method of operating a multi-mode communication unit. For each radio frame of a radio communication frame structure, the unit selectively sets a mode of radio frequency operation for one of transmission and reception for a selected radio frame duration, for operation in a radio communication mode of operation or in a sensing mode of operation. The unit may also interrupt a transmission task within a given radio frame at a time selected in accordance with a sensing instant of a second communication unit to which the data being transmitted and perform a different task for a duration of the sensing instant of the second communication unit.

Abstract: There is described the use of Digital Radio Frequency Memory (DRFM) modules to jam certain communication signals while allowing others to be received on a given frequency band. The DRFM modules exploit the multi-path phenomenon by using transmitted signals to cause full band destructive echoes and/or distortions. A set of receivers used in conjunction with the DRFM modules are aware of the exact multi-path induced by the DRFM modules and are therefore able to mitigate or even benefit from the effects of the destructive multi-path and maintain or improve communications.

Abstract: There is described a method of operating a multi-mode communication unit. For each frame of a data structure, the unit selectively sets a mode of operation for one of transmission and reception for a given duration, for operation in a radio communication mode of operation or in a sensing mode of operation. The unit interrupts a task within a given frame at a time selected in accordance with a set of priorities, and performs a different task for a given duration.

Abstract: The present invention is an additional tank that is mounted to an existing geothermal system for eliminating air into the pipes, preventing the damage into the pipes, ensuring a fluid without air and increasing the efficiency of the geothermal system.

Abstract: The present invention relates to a process for removing heavy metals and substantially destroying indicator bacteria present in municipal sludges, which comprises: lowering, under aerobic conditions, the pH of a municipal sludge from about 7 to 8 to about 2.0 to 2.5 by adding to said sludge 10% by volume of an inoculum containing a mixture of microorganisms comprising Thiobacillus thiooxidans ATCC 55127 and Thiobacillus thioparus ATCC 55128 with 1 to 3 g per liter of sulphur, and incubating for a period of at least 40 hours where the heavy metals originally present in said sludge have been substantially solubilized and the concentration of the indicator bacteria have been lowered to a non-toxic level; and recovering the metals from the low pH treated sludge of step a).