Dual mode electronic toll collection transponder

1. A transponder for engaging in RF communications with a roadside reader from a vehicle, comprising:

an antenna;

an electronic toll collection (ETC) component, the ETC component including an RF transceiver coupled to said antenna for modulating outgoing signals and for demodulating received signals, and a controller for implementing a pre-defined ETC communications protocol to detect and interpret said received signals and generate response signals for transmission as said outgoing signals when operating in an ETC mode, and wherein the ETC component includes a bypass port; and

an external interface coupled to said bypass port and having an external port for receiving input signals,

wherein said controller includes a bypass module for receiving a bypass instruction and entering a bypass mode, wherein in said bypass mode said input signals are relayed from said external interface to said RF transceiver for transmission as said outgoing signals.

2. The transponder claimed in claim 1 , wherein said ETC component comprises an application-specific integrated circuit or a gate array.

3. The transponder claimed in claim 1 , wherein the received signals from the roadside reader contain the bypass instruction, and wherein said controller includes a component for detecting the bypass instruction in the demodulated received signals.

4. The transponder claimed in claim 1 , further including a microcontroller connected to said bypass port for implementing a non-ETC application, said microcontroller having an input/output port connected to said external interface, and wherein said microcontroller receives the demodulated received signals from said bypass port.

5. The transponder claimed in claim 4 , wherein said microcontroller includes a detection module for detecting whether the received signals relate to an ETC transaction or said non-ETC application, and if related to said non-ETC application, generating said bypass instruction and sending said bypass instruction to said controller.

6. The transponder claimed in claim 5 , wherein said external interface is adapted to be connected to a vehicle information system, and wherein said non-ETC application includes reading and writing to said vehicle information system from the roadside reader.

7. The transponder claimed in claim 6 , further including a memory buffer for temporarily storing data read from the vehicle information system.

8. The transponder claimed in claim 7 , wherein the data read from the vehicle information system comprises emissions data, and wherein said non-ETC application comprises an emissions certification program.

9. The transponder claimed in claim 1 , wherein said external interface is configured to connect to a peripheral device to enable the peripheral device to communicate with the roadside reader for a non-ETC application.

10. The transponder claimed in claim 9 , wherein the peripheral device includes a biometric identification device, and wherein the non-ETC application includes providing biometric user identity data to the roadside reader.

11. The transponder claimed in claim 10 , wherein the biometric identification device comprises a fingerprint scanner.

12. The transponder claimed in claim 1 , wherein said external interface is configured to connect to a vehicle information system, and said outgoing signals include vehicle data from said vehicle information system.

13. The transponder claimed in claim 12 , wherein said vehicle data includes emissions data.

14. A transponder for engaging in RF communications with a roadside reader from a vehicle, comprising:

means for propagating an outgoing signal and receiving an incoming signal;

means for modulating an information signal to generate the outgoing signal and demodulating the incoming signal to generate a received signal;

means for controlling the means for modulating to implement a pre-defined ETC communications protocol by receiving the received signal and generating the information signal when operating in an ETC mode; and

means for interfacing with an external device to receive external signals and input the external signal to the means for controlling,

wherein said means for controlling includes means for bypassing the pre-defined ETC communications protocol by receiving a bypass instruction and entering a bypass mode, wherein in said bypass mode said external signals are relayed from said means for interfacing to said means for modulating for transmission as said outgoing signal.

15. The transponder claimed in claim 14 , wherein the received signal from the roadside reader contains the bypass instruction, and wherein said means for controlling detects the bypass instruction in the demodulated received signals.

16. The transponder claimed in claim 14 , further including a control means for implementing a non-ETC application connected to the means for controlling and connected to the means for interfacing, and wherein said control means receives the received signal via the means for controlling.

17. The transponder claimed in claim 16 , wherein said control means includes means for detecting whether the received signals relate to an ETC transaction or said non-ETC application, and if related to said non-ETC application, generating said bypass instruction and sending said bypass instruction to said means for controlling.

18. The transponder claimed in claim 17 , wherein said means for interfacing is configured to be coupled to a vehicle information system, and wherein said non-ETC application includes reading and writing to said vehicle information system from the roadside reader.

19. The transponder claimed in claim 18 , further including buffer means for storing selecting data from the vehicle information system in response to a buffer instruction from the roadside reader.

20. The transponder claimed in claim 14 , wherein said means for interfacing is configured to connect to a peripheral device to enable the peripheral device to communicate with the roadside reader for a non-ETC application.

21. The transponder claimed in claim 20 , wherein the peripheral device includes a biometric identification device, and wherein the non-ETC application includes providing biometric user identity data to the roadside reader.

22. The transponder claimed in claim 14 , wherein said means for interfacing is configured to connect to a vehicle information system, and said outgoing signals include vehicle data from said vehicle information system.

23. The transponder claimed in claim 22 , wherein said vehicle data includes emissions data.

24. A method for engaging in RF communications between a dual purpose vehicle-mounted transponder and a roadside reader, the transponder having an ETC controller for implementing a predefined ETC communications protocol, the method comprising the steps of:

receiving an incoming signal from the roadside reader;

demodulating the incoming signal to generate a received signal;

determining whether the received signal relates to an ETC transaction or a non-ETC application;

generating a response signal in accordance with a pre-defined ETC communications protocol by the ETC controller and transmitting the response signal to the roadside reader, if the received signal relates to said ETC transaction; and

receiving input data from an external device and transmitting the input data to the roadside reader, if the received signal relates to said non-ETC application.