Abstract: A method significantly reduces the average power for radio communication in a communication system, such as a system that has applications requiring low communication latency. The method may use a low power radio communication circuit (e.g., a non-heterodyne receiver) to wait for a communication request, taking advantage of the low power consumption of the radio communication circuit. Subsequent to receiving and validating the communication request, the communication system may switch to a more efficient—but higher power—communication circuit. Thus, effective communication is achieved without making undesirable tradeoffs, such as reduced sensitivity.

Abstract: Wireless communication protocols are provided for wireless device discovery, preferably (but not necessarily) with low power consumption. Some protocols are suitable for wireless locks and keys (e.g. smart cards and card readers).

Abstract: Methods and systems are provided for a universal key that enables a user to have access to any type of secured portal, both physical and electronic, in a wireless, hands-free, distance-independent manner without requiring contact or line of sight access between the key and the secured portal. The universal key is not distance-dependent, and each secured portal can be provided with its own prescribed activation range, if desired. Some portals may be provided with long range activation, such as 50 feet, while other portals may be provided with short range activation of a few feet or less. The type of portal being secured and the range of activation may be selected by the user and is not limited by the universal key. In addition, the universal key will provide access to the secured portals in a hands-free fashion so that the user need not push any buttons or take any other action in order to obtain access to the portal.