Abstract: A driver alerting device includes a transceiver adapted for mounting at the rearward end of a vehicle for directing its wave output rearwardly of the vehicle. Return wave signals for many objects within the transceiver range are picked up and supplied to the transceiver by an antenna. Any resultant doppler shift signal is amplified for driving an audio alarm adapted for placement within the passenger compartment of the vehicle. The circuit is adapted for electrical connection to the back-up light circuit of the vehicle for activation only when the vehicle transmission is engaged in reverse gear.

Abstract: A driver alerting device includes a transceiver adapted for mounting at the rearward end of a vehicle for directing its wave output rearwardly of the vehicle. Return wave signals for many objects within the transceiver range are picked up and supplied to the transceiver by an antenna. Any resultant doppler shift signal is amplified for driving an audio alarm adapted for placement within the passenger compartment of the vehicle. The circuit is adapted for electrical connection to the back-up light circuit of the vehicle for activation only when the vehicle transmission is engaged in reverse gear.

Abstract: An alarm device for a construction vehicle including a transceiver adapted for mounting at the rearward end of a vehicle for directing its wave output rearwardly of the vehicle. Return wave signals for many objects within the transceiver range are picked up and supplied to the transceiver by an antenna. Any resultant doppler shift signal is amplified for driving an audio alarm positioned on the vehicle. The circuit is adapted for electrical connection to the reverse gear of the vehicle for activation only when the vehicle transmission is engaged in reverse gear.