Mobile telephone messaging by baseband envelope modulation

• US 20040076129A1
• Filed: 10/22/2002
• Published: 04/22/2004
• Est. Priority Date: 10/22/2002
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Inventors: Vannucci, Giovanni
• Granted Patent: US 7,349,365 B2
• Time in Patent Office: Days
• US Class Current: 370/335
• CPC Class Codes: H04W 4/00 Services specially adapted for wireless communication networks; Facilities therefor
• CPC Class Codes: H04W 4/12 Messaging; Mailboxes; Announcements
• CPC Class Codes: H04W 76/20 Manipulation of established connections
• CPC Class Codes: H04W 88/18 Service support devices; Network management devices

Abstract

A method and system communicates messages using a radio signal. The radio signal is transmitted according to an air interface standard for wireless radio communications. A baseband envelope of the transmitted radio signal is modulated while maintaining compliance with the air interface standard to encode a message in the radio signal. A receiver demodulates the baseband envelope to decode the message. The transmitter and receiver can be part of a cellular telephone network including mobile telephones and base stations.

Claims

1. A method for communicating messages using a radio signal, comprising:

transmitting a radio signal according to an air interface standard for wireless radio communications;

modulating a carrier of the transmitted radio signal while maintaining compliance with the air interface standard to send a first message to a first receiver compliant with the air interface standard; and

modulating a baseband envelope of the transmitted radio signal while maintaining compliance with the air interface standard to send a second message to a second receiver, the modulating of the carrier occurring concurrently with the modulating of the baseband envelope.

2. The method of claim 1 wherein the transmitter is a mobile telephone, the first receiver is a base station, and the second receiver is a baseband envelope detector.

3. The method of claim 1 wherein the transmitter is a base station, the first receiver is a mobile telephone, and the second receiver is a baseband envelope detector.

4. The method of claim 1 wherein the air interface standard uses time division multiple access.

5. The method of claim 1 wherein the air interface standard uses code division multiple access.

6. The method of claim 1 further comprising:

modifying durations of bursts of the radio signal to modulate the baseband envelope.

7. The method of claim 1 further comprising:

modifying times of occurrences of burst of the radio signal to modulate the baseband envelope.

8. The method of claim 1 further comprising:

modifying an amplitude of bursts of the radio signal to modulate the baseband envelope.

9. The method of claim 1 further comprising:

modifying a number of the bursts of the radio signal to modulate the baseband envelope.

10. The method of claim 1 further comprising:

sending the radio signal as burst including a first type of burst and a second type of burst to modulate the baseband envelope.

11. The method of claim 1 further comprising:

simulating voice activity in the radio signal to modulate the baseband envelope.

12. The method of claim 3 wherein the second receiver detects parameters of an uplink channel of the transmitter to determine a downlink channel of the transmitter.

13. The method of claim 12 wherein the detected parameters include a carrier frequency and a time division multiple access slot.

14. The method of claim 12 wherein the detected parameters include a time of occurrence of a burst of transmission.

15. The method of claim 12 wherein the detected parameters include a frequency-hopping pattern.

16. The method of claim 12 wherein the detected parameters include a Walsh code.

17. The method of claim 2 wherein the second message contains an identification of the transmitter.

18. The method of claim 3 wherein the second message contains an identification of the mobile telephone.

19. The method of claim 1 wherein the second message contains a unique code.

20. The method of claim 19 wherein the unique code is an authentication code for a commercial transaction.

21. The method of claim 19 wherein the unique code is provided by an automatic answering unit.

22. The method of claim 1 further comprising:

adjusting a sensitivity of the second receiver to require the transmitter to be within a predetermined distance of the second receiver.

23. The method of claim 22 wherein the predetermined distance is less than a meter.

24. The method of claim 22 wherein the predetermined distance is less than five centimeters.

25. The method of claim 1 wherein the second receiver includes an uplink receiver and a downlink receiver.

26. The method of claim 1 wherein the second receiver is connected to an automated vending machine, and further comprising:

completing a transaction in the vending machine in response to receiving the second message in the second receiver.

27. The method of claim 1 wherein the second receiver is connected to a cash register, and further comprising:

completing a transaction in the cash register machine in response to receiving the second message in the second receiver.

28. The method of claim 2 further comprising:

verifying the second message in a server; and

notifying the second receiver of the verification.

29. The method of claim 28 wherein the server is connected to the base station.

30. The method of claim 1 wherein the transmitter includes a subscriber information module card to perform the modulating.

31. The method of claim 1 further comprising:

examining caller-ID information associated with the transmitter.

32. The method of claim 1 wherein the modulating of the carrier uses digital phase-shift keying.

33. A system for communicating messages using a radio signal, comprising:

a transmitter configured to transmit a radio signal according to an air interface standard for wireless radio communications, the transmitter further comprising means for modulating a carrier of the transmitted radio signal while maintaining compliance with the air interface standard to encode a first message and means for modulating a baseband envelope of the transmitted radio signal while maintaining compliance with the air interface standard to encode a second message, the modulating of the carrier occurring concurrently with the modulating of the baseband envelope; and

a receiver configured to receive the radio signal according to the air interface standard for wireless radio communications, the receiver further comprising means for demodulating the baseband envelope of the received radio signal to decode the second message.