DUAL CONVERSION TRANSMITTER WITH SINGLE LOCAL OSCILLATOR

• US 20100117693A1
• Filed: 11/06/2009
• Published: 05/13/2010
• Est. Priority Date: 11/07/2008
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: ViaSat Incorporated
• Inventors: Buer, Kenneth V., Lorg, Shawn M.
• Granted Patent: US 8,385,855 B2
• Time in Patent Office: Days
• US Class Current: 327/156
• CPC Class Codes: H03D 7/163 the local oscillations of at least two of the frequency changers being derived from a single oscillator

Abstract

The present disclosure relates to systems, devices and methods related to transmitters, and/or transceivers having a single, tunable oscillator in a dual conversion architecture. In various exemplary embodiments, this transmitter may include: a first mixer configured to receive a first oscillator signal from the single oscillator; a filter configured to band pass filter the converted signal and output a filtered signal; and a second mixer in communication with the filter, configured to receive the filtered signal. This dual conversion transmitter may be configured to receive a communication signal from an input to the transmitter and to output a converted signal based on the first oscillator signal and the communication signal. The second mixer may be configured to receive a scaled version of the first oscillator signal and to output a desired frequency output signal based on the scaled version of the first oscillator signal and the filtered signal.

Claims

1. An electronic device comprising:

a first mixer configured to receive a first oscillator signal;

the first mixer configured to receive a communication signal from an input to the electronic device;

the first mixer configured to output a converted signal based on the first oscillator signal and the communication signal;

a filter configured to remove undesired spurious signals from the converted signal and output a filtered signal; and

a second mixer in communication with the filter and configured to receive the filtered signal, the second mixer configured to receive a scaled version of the first oscillator signal;

the second mixer in communication with an output of the electronic device and configured to output an output signal based on the scaled version of the first oscillator signal and the filtered signal;

wherein the electronic device comprises one of;

a multiple conversion transmitter, and a multiple conversion transceiver, and wherein the output signal has an output frequency that is tunable over an output frequency range by adjusting a frequency associated with the first oscillator signal over a first oscillator signal frequency range.

2. The electronic device of claim 1, wherein the multiple conversion transmitter is a dual conversion transmitter.

3. The electronic device of claim 1, wherein the output of the electronic device is an RF transmit signal, and wherein the RF transmit signal is configured to be frequency tuned to a desired color pattern.

4. The electronic device of claim 3, wherein the RF transmit signal is tunable over a transmit frequency range.

5. The electronic device of claim 4, wherein the frequency range is equal to a selected frequency range of a provided satellite transmitter.

6. The electronic device of claim 4, wherein the frequency tuning is one of:

actuated electronically and actuated manually.

7. The electronic device of claim 4, wherein the transmit frequency range has a selectable start point and a selectable end point.

8. The electronic device of claim 4, wherein the electronic device is configured for tuning the frequency range so as to communicate using the operating frequency range of any spot beam satellite.

9. The electronic device of claim 1, wherein said electronic device does not comprise a filter bank.

10. The electronic device of claim 1, further comprises SiGe semiconductor material.

11. The electronic device of claim 1, further comprising a multiplier, wherein the multiplier is configured to scale the first oscillator signal to create the scaled version of the first oscillator signal, which is provided to the second mixer.

12. The electronic device of claim 1, wherein the electronic device is configured to create RF transmit signals and RF receive signals that each comprise one of:

K band frequencies, Ka band frequencies, FCC assigned internet access band frequencies, home satellite band frequencies, and KuTV band frequencies.

13. The electronic device of claim 1, further comprising a single oscillator configured to provide the first oscillator signal, wherein said first oscillator signal is not scaled in frequency using a phase lock loop.

14. A dual conversion transmitter, wherein the transmitter is configured to divide a first oscillator signal into a second oscillator signal and a third oscillator signal, wherein the transmitter is configured to perform frequency scaling such that the second and third oscillator signals have different frequencies from each other, the transmitter further comprising:

a first mixer, wherein the first mixer is configured to utilize the second oscillator signal to facilitate frequency conversion; and

a second mixer, wherein the second mixer is configured to utilize the third oscillator signal to facilitate frequency conversion; and

a filter configured to filter the output of the first mixer and to provide the output of the filter to the input of the second mixer.

15. The dual conversion transmitter of claim 14, the transmitter further comprising a first multiplier configured to scale the frequency of the third oscillator signal such that the second and third oscillator signals have different frequencies from each other.

16. The dual conversion transmitter of claim 14, the transmitter further comprising a sub-harmonic mixer configured to scale the frequency of the third oscillator signal such that the second and third oscillator signals have different frequencies from each other.

17. The dual conversion transmitter of claim 14, wherein the transmit frequency conversion is the result of one of:

(i) the sum of an intermediate frequency (“

IF’

) transmit signal frequency and the third oscillator signal frequency, and (ii) the difference of the IF transmit signal frequency and the third oscillator signal frequency.

18. The dual conversion transmitter of claim 14, wherein the multiple conversion transmitter expands the intermediate frequency bandwidth with each subsequent conversion.

19. A method of producing an output signal via a dual conversion transmitter comprising:

receiving a first oscillator signal, wherein the first oscillator signal is provided by a single tunable oscillator;

receiving a communication signal from an input to the dual conversion transmitter, wherein a first mixer is configured to receive the communication signal;

providing a converted signal based on the first oscillator signal and the communication signal, wherein the first mixer is configured to output the converted signal;

band pass filtering the converted signal to create a filtered signal, wherein a filter is configured to provide the band pass filtering;

receiving the filtered signal, wherein a second mixer is in communication with the filter and configured to receive the filtered signal;

converting the filtered signal, in the second mixer, based on a scaled version of the first oscillator signal, wherein the second mixer is in communication with an output of the dual conversion transmitter; and

delivering an output signal based on the scaled version of the first oscillator signal and the filtered signal to the output.

20. The method of claim 19, further comprising expanding an intermediate frequency bandwidth with each subsequent conversion.