Wireless power transfer with in-band preamble monitoring and control

A device comprising:

• a first circuit configured to be coupled with a coil and at least one of transmit or receive a first signal providing wireless power through the coil, wherein the first signal is further modulated with one or more second signals associated with one or more communication channels through the coil, wherein a packet within any of the one or more second signals includes one or more first bits associated with a preamble and one or more second bits associated with data;
• a rectifier configured to generate a rectified version of the first signal;
• a controller configured to:
• measure temporal variations of at least one of the first signal, the rectified version of the first signal, or the one or more second signals;
• and
• determine one or more thresholds for distinguishing between at least one of the one or more first bits or the one or more second bits in the packet based on the temporal variations during a buffer interval;
• and
• a second circuit configured to:
• demodulate the one or more second signals using the one or more thresholds to identify the preamble of the packet;
• and
• extract the one or more second signals associated with the data from the packet in response to identifying the preamble of the packet;
• wherein the modem is further configured to wait the buffer interval prior to demodulating the one or more second signals using the one or more thresholds to identify the preamble of the packet.

A method comprising:

• receiving a first signal providing wireless power through a coil, wherein the first signal is further modulated with one or more second signals associated with one or more communication channels through the coil, wherein a packet within any of the one or more second signals includes one or more first bits associated with a preamble and one or more second bits associated with data;
• measuring temporal variations of at least one of the first signal, a rectified version of the first signal, or the one or more second signals;
• determining one or more thresholds for distinguishing between at least one of the one or more first bits or the one or more second bits in the packet based on the temporal variations during a buffer interval;
• demodulating the one or more second signals using the one or more thresholds to identify the preamble of the packet;
• and
• extracting the one or more second bits associated with the data from the packet in response to identifying the preamble of the packet;
• wherein the modem is further configured to wait the buffer interval prior to demodulating the one or more second signals using the one or more thresholds to identify the preamble of the packet.