Universal transmitter

• US 6,556,813 B2
• Filed: 06/19/2001
• Issued: 04/29/2003
• Est. Priority Date: 11/09/1998
• Status: Expired due to Fees

• Current Assignee: Philip Y.W. Tsui
• Original Assignee: Philip Y.W. Tsui
• Inventors: Tsui, Philip Y.W.
• Primary Examiner(s): Nguyen, Lee
• Application Number:
  US09/885,466
• Publication Number:
  US 20010034213A1
• Time in Patent Office: 679 Days
• Field of Search: 455/92, 455/88, 340/825.22, 340/825.69, 340/825.72, 340/825.73, 341/173, 341/176
• US Class Current: 455/92
• CPC Class Codes: G08C 19/28 using pulse code
• CPC Class Codes: G08C 2201/92 Universal remote control
• CPC Class Codes: H04B 1/0346 Hand-held transmitters

Abstract

A method and apparatus for providing a universal transmitter that can detect and emulate a transmission signal of a transmitter, the transmission signal having a corresponding transmission frequency and a corresponding modulation pattern. The universal transmitter comprises: a detection circuit that detects a frequency and a modulation pattern of a transmitted signal of a separate transmitter and a memory. A processor coupled to the detection circuit and the memory, stores a frequency value representative of the detected frequency and a plurality of value representative of the detected modulation pattern, in the memory. A transmitting circuit coupled to the processor, is operable to transmit an output signal having the frequency and the modulation pattern of the transmission signal.

Claims

1. A method of detecting and emulating a transmission signal of a transmitter, the transmission signal having a corresponding transmission frequency and a corresponding modulation pattern, the method comprising:

receiving the transmission signal;

conditioning the received signal to provide a signal having enhanced transitions;

determining a number of said enhanced transitions;

determining a plurality of timing intervals between each enhanced transition, each of said plurality of timing intervals corresponding to one of a first state and a second state;

determining the transmission frequency and the modulation pattern based on the number of counts and the timing interval between each enhanced transition;

storing the transmission frequency and the modulation pattern in memory; and

transmitting an output signal having the transmission frequency and the modulation pattern, in response to an enable signal.

2. The method of claim 1, further comprising:

pre-scaling the received signal by dividing the frequency of the received signal by a predetermined value; and

determining the transmission frequency and the modulation pattern based on the number of counts, the timing interval between each enhanced transition, and the predetermined value.

3. The method of claim 1, wherein the transmission frequency is in the radio frequency range.

4. The method of claim 1, wherein said first state is an ON state and said second state is an OFF state.

5. The method of claim 1, further comprising:

storing said plurality of timing intervals in memory; and

,

determining a pattern of said plurality of timing intervals.

6. The method of claim 5, wherein storing said plurality of timing intervals comprises storing a plurality of entries in a table in memory, said entries corresponding to said plurality of timing intervals.

7. The method of claim 6, wherein determining a pattern comprises examining the plurality of entries in said table for the presence of a repeating pattern of said plurality of timing intervals.

8. A universal transmitter, comprising:

an antenna to receive a signal transmitted from another transmitter;

a detection circuit coupled to the antenna, the detection circuit including;

a wave shaping circuit coupled to the antenna, the wave shaping circuit to level shift and condition the received signal to provide enhanced transitions, and

a wave envelope detection circuit coupled to the antenna, the wave envelope detection circuit to detect the envelope of the received signal for determining a plurality of timing intervals corresponding to the modulation pattern of the received signal;

a processor coupled to the detection circuit, the processor to determine the frequency and the modulation pattern of the received signal based on the output of the wave shaping circuit and the output of the wave envelope detection circuit;

a memory coupled to the processor, the processor to store a frequency value representative of the detected frequency and a plurality of values representative of the modulation pattern of the received signal, in the memory; and

a transmitting circuit coupled to the processor, the transmitting circuit being operable to transmit an output signal having the frequency and modulation pattern of the received signal.

9. The transmitter of claim 8, wherein the processor to determine the frequency of the received signal based on a pulse count from the output of the wave shaping circuit and the plurality of timing intervals from the wave envelope detection circuit.

10. The transmitter of claim 8, wherein the processor to determine the frequency of the received signal based on a pulse count from the output of the wave shaping circuit and an interval of time representing the time elapsed during the pulse count.

11. The transmitter of claim 8, wherein the functionality of the wave shaping circuit and the wave envelope detection circuit is implemented as one circuit.

12. The transmitter of claim 8, wherein the detection circuit further comprises:

a pre-scaler circuit to scale the received signal by dividing the frequency of the received signal by a predetermined value, wherein the wave shaping circuit and the wave envelope detection circuit receive the scaled signal from the pre-scaler.

13. The transmitter of claim 12, wherein the processor to determine the frequency of the received signal based on a pulse count from the wave shaping circuit, the plurality of timing intervals from the wave envelope detection circuit, and the predetermined value.

14. The transmitter of claim 12, wherein the processor to determine the frequency of the received signal based on a pulse count from the output of the wave shaping circuit, an interval of time representing the time elapsed during the pulse count, and the predetermined value.