Antenna providing variable communication with an implant

A sleep apnea treatment device, comprising:

• a primary antenna configured to be located external to a subject,
• at least one processor in electrical communication with the primary antenna, the
• at least one processor configured to:
• cause transmission of a primary signal from the primary antenna to an implantable device implanted in the subject on a genioglossus muscle proximal to a hypoglossal nerve of the subject, wherein the implantable device includes at least one pair of modulation electrodes,
• wherein the processor is further configured to adjust one or more characteristics of the primary signal to generate a sub-modulation control signal adapted to cause a current at the at least one pair of modulation electrodes below a neuromuscular modulation threshold of the hypoglossal nerve when received by the implantable device and to generate a modulation control signal adapted to cause a current at the at least one pair of modulation electrodes above a neuromuscular modulation threshold of the hypoglossal nerve when received by the implantable device.