Abstract: Techniques described here introduce signature frequency modulation to unmodulated pulse signals as frequency chirps to enhance the security of multi-carrier phase-based ranging signals. The characteristics of the chirps may be mutually known by an initiator and a desired reflector of the ranging applications. The characteristics of the chirps may vary between the multi-carrier signals to thwart any attempt by an eavesdropper to predict the chirps. In one aspect, the characteristics of the chirps may be calculated for each timeslot of a ranging cycle by two authorized devices using a ciphering algorithm such as the Advanced Encryption Standard (AES) based on a shared security key. Each call of the AES may generate one or more pseudo-random numbers based on the shared security key and a time-varying initialization vector that increments every timeslot. Fields of the pseudo-random number may be extracted to determine the characteristics of the chirps associated with the timeslot.

Abstract: Apparatuses, systems, and methods for transmitting and multiplexing chirp signals for communications are provided. An example apparatus includes an antenna, a radio, and processing circuitry. The radio may be configured to transmit and receive wireless communications via the antenna, and the processing circuitry configured to establish a wireless communications link with a receiving communications device. The signaling transmitted by the antenna via the radio as controlled by the processing circuitry may include a plurality of sequenced chirp signals within an orthogonal frequency division multiplexing (OFDM) framework.

Abstract: Apparatuses, systems, and methods for transmitting and multiplexing chirp signals for communications are provided. An example apparatus includes an antenna, a radio, and processing circuitry. The radio may be configured to transmit and receive wireless communications via the antenna, and the processing circuitry configured to establish a wireless communications link with a receiving communications device. The signaling transmitted by the antenna via the radio as controlled by the processing circuitry may include a plurality of sequenced chirp signals within an orthogonal frequency division multiplexing (OFDM) framework.