Abstract: A strap band including a flexible wire bus having electrodes and wires coupled with the electrodes is described. The strap band may be coupled with a device that includes circuitry configured to drive signals on some of the electrodes and receive signals from non-driven electrodes. The signal frequency applied to driven electrodes may be varied to increase/decrease signal penetration depth to sense different body structures positioned at different depths in the body portion. Different frequencies for different types of measurements may be selected to optimize sensing of bio-impedance, galvanic skin response, hear rate, respiration, heart rate variability, hydration, inflammation, stress, and arousal in sympathetic nervous system. A system clock frequency may be one of the frequencies used. A magnitude of the drive signal, a gain on the received signal or both, may be adjusted based on the frequency selected and/or to sense signals from the body structure(s) of interest.

Abstract: A strap band including a flexible wire bus having electrodes and wires coupled with the electrodes is described. The strap band may be coupled with a device that includes circuitry configured to drive signals on some of the electrodes and receive signals from non-driven electrodes. The electrode spacing and strap band dimensions may be selected to form a strap band that may accommodate a wide range of user body sizes for a target region the electrodes are positioned in contact with. The electrodes may be composite electrodes having multiple layers of conductive material in which an outermost layer is made from a material operative as an ion exchange layer. The ion exchange layer in contact with an electrolyte layer of a body portion may be operative to reduce motion artifact induced impedance and increase a signal to noise ratio for bio-impedance circuitry or other biometric circuitry coupled with the electrodes.