A phase-calibration circuit including a pattern generator, a phase adjuster, a rotate register unit, a detector unit, and an optimization unit is disclosed. The system comprises a base station, at least one indoor antenna connected to the base station providing coverage in an indoor coverage area and means for detecting human presence in a detection area. Both of the inner sleeve and the outer sleeve are located outside of the tubing flange and the tubing segment. The potassium iodide is preferably in a mole ratio with the tannic acid of 1:2. The contact pads include a first contact pad with a first end proximate to the second longitudinal edge and a second contact pad with a second end proximate to the second longitudinal edge.