Abstract: A communication device includes a directional antenna, and a control circuit. The directional antenna has a directional radiation pattern for directing greater power of a transmitted signal in a specific direction. The control circuit is coupled to the directional antenna and determines an angle and a distance to another device. Based on the determined distance and angle to the another device, the control circuit selects a security level from a plurality of security levels for communication between the device and the another device. In another embodiment, a method for transmitting data between the first and second devices is provided.

Abstract: A communication device includes a directional antenna, and a control circuit. The directional antenna has a directional radiation pattern for directing greater power of a transmitted signal in a specific direction. The control circuit is coupled to the directional antenna and determines an angle and a distance to another device. Based on the determined distance and angle to the another device, the control circuit selects a security level from a plurality of security levels for communication between the device and the another device. In another embodiment, a method for transmitting data between the first and second devices is provided.

Abstract: To minimize abrupt changes in modulated signal amplitude when switching between modulation types in a multi-modulation system, a “smoothing” circuit is used. When the modulation type is changed in a multi-slot modulation, the last symbol of the previous slot is overwritten and modulation is controlled by a smoothing circuit during the time of the final symbol of the previous slot to effect the trajectory smoothing. The IQ-plane is divided into two (or more) zones, each with an associated safe point. After the next-to-last symbol is modulated, modulation is made to jump to the safe point associated with the zone and modulation continues to a starting point. From the starting point, the next slot can be modulated using the new modulation type.

Abstract: To minimize abrupt changes in modulated signal amplitude when switching between modulation types in a multi-modulation system, a “smoothing” circuit is used. When the modulation type is changed in a multi-slot modulation, the last symbol of the previous slot is overwritten and modulation is controlled by a smoothing circuit during the time of the final symbol of the previous slot to effect the trajectory smoothing. The IQ-plane is divided into two (or more) zones, each with an associated safe point. After the next-to-last symbol is modulated, modulation is made to jump to the safe point associated with the zone and modulation continues to a starting point. From the starting point, the next slot can be modulated using the new modulation type.