Abstract: A traffic preemption system comprising a vehicle preemption unit configured to mount to a vehicle and transmit a signal comprising one or more identifying pulses, a detection unit configured to, receive the signal transmitted by the vehicle preemption unit, identify a characteristic of the vehicle preemption unit using the one or more identifying pulses, and calculate a timing delay based on the identified characteristic of the vehicle preemption unit, and an intersection preemption unit configured to receive the timing delay from the detection unit and change a traffic light in response to the timing delay.

Abstract: A laser emitter for a traffic control preemption system, the laser emitter comprising a laser emitting diode or array configured to emit a laser beam, one or more optics coupled to the laser emitting diode and configured to shape the laser beam, and a control module configured to trigger emission of the laser beam at a predetermined frequency and for a predetermined duration in accordance with one or more requirements of the traffic control preemption system.

Abstract: A traffic preemption system comprising an intersection control module, an intersection preemption unit comprising a signal detector configured to receive a signal transmitted by a vehicle preemption unit mounted to a vehicle and a remotely located electronic device comprising a controller configured to detect a variation in voltage. The system further comprises a cable coupling the intersection controller, the intersection preemption unit, and the remotely located electronic device, the cable comprising a power wire configured to carry a modulated voltage level and share power among the intersection preemption unit and the remotely located electronic device, a ground wire, and a communications wire configured to transmit a communications signal between the intersection preemption unit and the intersection controller.

Abstract: A bias compensating remote audience survey system (34) is configured to identify radio stations (162) to which tuners (24) are tuned. The tuners (24) have predetermined signals (26) emitted therefrom. The survey system (34) employs a method (152) of compensating for a station bias, or preference, toward or against one or more of radio stations (162). The method (152) includes measuring durations (62) over which the predetermined signals (26) are received by the survey system (34). The durations (62) are then combined by averaging to form a station average detection length (ADL) value (74) specific to one of the radio stations (162). The station ADL value (74) is compared to a multi-station ADL parameter (86). A sensitivity level (146) for the one radio stations (162) is adjusted in response to the comparison to compensate for station bias.

Abstract: An interference attenuating remote audience survey system (42) is configured to identify radio stations (84) to which tuners (26) are tuned, the tuners (26) having local oscillator (LO) signals (30) emitted therefrom. The system (42) includes a first antenna (34) for sensing a first signal (52) at a selected LO frequency (88), the first signal (52) including one of the LO signals (30) and an interference signal (96). A second antenna (44) receives a second signal (54) at the selected LO frequency (88), the second signal (54) including an interference signal (100). A shield element (48) shields the second antenna (44) from receiving the one of the LO signals (30). The first and second signals (52, 54) are subtractively combined to produce a third signal (77), the interference signal (96) being attenuated from the third signal (77).

Abstract: A survey system (52, 154) is configured to identify radio stations (92) to which tuners (26) are tuned. The tuners (26) have predetermined signals (30) emitted therefrom. In one embodiment, the survey system (52) employs a method (86) which includes selecting one of the predetermined signals (30), receiving at a receiver (54) a second signal (116), and determining that one of the tuners (26) is tuned to one of the radio stations (92) when a harmonic (44, 46) of the fundamental frequency (42) of the predetermined signal (30) is detected within the second signal (116). In an alternative embodiment, the survey system (154) employs a method (182) that includes generating and broadcasting a survey signal (162) that is a one of the predetermined signals (30) modified to incorporate a signal identifier (212, 216).

Abstract: An active broadcast survey system (32) is configured to identify radio stations (216) to which tuners (26) are tuned. The tuners (26) have local oscillator signals (30) emitted therefrom. The survey system (32) employs a method (210) that includes generating and broadcasting a survey signal (42) that is a one of the local oscillator signals (30) modified to incorporate a signal identifier (236, 240). The method (182) further includes detecting a harmonic (54, 56) of the fundamental frequency (52) of the local oscillator signal (30) within a received broadcast signal (44) and determining that one of the tuners (26) is tuned to one of the radio stations (216) when the detected harmonic (54, 56) includes the signal identifier (236, 240). The survey system (32) also employs a method (166) for active tuning of the system (32), and another method (282) for providing short range communication with a remote transceiver (280) to facilitate uploading and downloading of system settings and data.

Abstract: A bias compensating remote audience survey system (34) is configured to identify radio stations (162) to which tuners (24) are tuned. The tuners (24) have predetermined signals (26) emitted therefrom. The survey system (34) employs a method (152) of compensating for a station bias, or preference, toward or against one or more of radio stations (162). The method (152) includes measuring durations (62) over which the predetermined signals (26) are received by the survey system (34). The durations (62) are then combined by averaging to form a station average detection length (ADL) value (74) specific to one of the radio stations (162). The station ADL value (74) is compared to a multi-station ADL parameter (86). A sensitivity level (146) for the one radio stations (162) is adjusted in response to the comparison to compensate for station bias.

Abstract: A survey electronics package (32) of a survey system (10) includes a transmitter (36) and a receiver (38). The transmitter (36) transmits a survey signal which a radio (12) residing in a detection zone (14) receives and demodulates to generate an audio echo signal. The audio echo signal is magnetically radiated from a speaker (26) of the radio (12). The receiver (38) magnetically senses this magnetically radiated audio echo signal. A bandpass filter (48) in the receiver (38) and a correlation process (86) insure that only a valid audio echo signal is recorded. When the detection of a valid audio echo signal corresponds to a radio (12) tuned to a particular radio station, a record is made of the detection.

Abstract: A system for estimating listening audience characteristics in response to radio broadcast programming includes a central office, a plurality of remote survey sites, and a plurality of remote access sites. The survey sites collect survey data describing radio stations to which vehicle-mounted tuners are tuned. The survey data is downloaded to the central office, where the survey data is associated with a radio program broadcast by a radio station. The survey data and the radio program are presented at the remote access sites in a substantially synchronous format such that audience responses to specific radio programming can be observed.

Abstract: A system and method for counting vehicles by detecting RF signals emitted from a portion of the vehicles is provided. An RF scanner/receiver located at a testing site is tuned to receive local oscillator (LO) signals that may be emitted from radio tuners located in a portion of the vehicles. A control unit controls the scanner/receiver, stores data related to the received LO signals, and performs other operating procedures. A central computer in data communication with the control unit performs data translation operations on the raw LO signal data. Scale factors derived from calibration formulas are applied to the system data to provide an estimated vehicle count and an estimated average vehicle speed. The central computer formats the resulting data for presentation to a user.

Abstract: An antenna (26) projects a detection zone (28) across a non-intersection portion (16) of a road (10). A scanning receiver (32) couples to and is controlled by a data logging computer (34). This computer (34) commands the receiver (32) to look for one FM local oscillator (LO) signal (22) that may be emitted from within the detection zone (28). If one LO signal (22) is detected, other LO signals (22) that may be detected at the receiver are ignored until the one signal is no longer detectable (90-106). An attenuator allows LO signals 22 emitted from radios (20) in the detection zone (28) at noisy frequencies to have the same likelihood of being detected as LO signals 22 emitted at less noisy frequencies. Detected LO signals (22) are ignored if they are detected for less than a minimum duration (100) or if they are detected for greater than a maximum duration (118).

Abstract: An antenna (26) projects a detection zone (28) across a non-intersection portion (16) of a road (10). A scanning receiver (32) couples to and is controlled by a data logging computer (34). This computer (34) commands the receiver (32) to look for one FM local oscillator (LO) signal (22) that may be emitted from within the detection zone (28). If one LO signal (22) is detected, other LO signals (22) that may be detected at the receiver are ignored until the one signal is no longer detectable (90-106). An attenuator allows LO signals 22 emitted from radios (20) in the detection zone (28) at noisy frequencies to have the same likelihood of being detected as LO signals 22 emitted at less noisy frequencies. Detected LO signals (22) are ignored if they are detected for less than a minimum duration (100) or if they are detected for greater than a maximum duration (118).