Frequency conversion device for wireless systems
A frequency conversion device for transforming a frequency of an input signal, the device comprising: a signal generator for providing a plurality N of first signals at a first frequency, where N≧1, from an input signal having an in-phase component I and a quadrature signal component Q; an oscillator for generating N parallel oscillation signals, wherein the N oscillation signals are stepped in phase with respect to one another; a mixer comprising N mixing components, each mixing component being coupled to receive a respective one of the plurality of first signals and coupled to receive a respective oscillation signal for mixing the respective first signal with the corresponding oscillation signal to provide an output signal; and a common amplifier for receiving the N output signals from the N mixing components in N sequential phases for transmission.
1. A frequency conversion device for transforming a frequency of an input signal, the device comprising:
a signal generator for providing a plurality N of first signals at a first frequency from an input signal having an in-phase component I and a quadrature signal component Q;
an oscillator for generating N parallel oscillation signals, wherein the N oscillation signals are stepped in phase with respect to one another;
a mixer comprising N mixing components, each mixing component being coupled to receive a respective one of the plurality of first signals and coupled to receive a respective oscillation signal for mixing the respective first signal with the corresponding oscillation signal to provide an output signal; and
a common amplifier for receiving the N output signals from the N mixing components in N sequential phases for transmission.
2. The device according to claim 1 wherein each mixing component comprises a switching arrangement including a first switch controlled by the respective oscillator signal for controlling provision of the corresponding first signal to the common amplifier.
3. The device according to claim 2 , wherein N is a multiple of 8; and the N first signals comprise a set of 8 signals comprising I−Q; √2×I; I+Q; √2×Q; −I+Q; −√2×I; −I−Q; and −√2×Q signals.
4. The device according to claim 3 wherein the switching arrangements are operable to supply the first signals to the common amplifier in the following sequential or reversed sequential order: I−Q; √2×I; I+Q; √2×Q; −I+Q; −√2×I; −I−Q; and −√2×Q.
5. The device according to claim 2 , wherein N is a multiple of 6; and the N first signals comprise a set of 6 signals comprising I−Q; 2×I+Q; I+2×Q; −I+Q; −2×I−Q; and −I−2×Q signals.
6. The device according to claim 5 wherein the switching arrangements are operable to supply the first signals to the common amplifier in the following sequential or reversed sequential order: I−Q; 2×I+Q; I+2×Q; −I+Q; −2×I−Q; and −I−2×Q.
7. The device according to claim 2 wherein each switching arrangement further comprises a second switch arranged in parallel to the first switch for receiving an opposing first signal to the first signal received at the first switch and controllable by the respective oscillation signal for provision of a differential output signal.
8. The device according to claim 1 , further comprising N signal amplifiers, each amplifier being arranged to amplify a respective first signal.
9. The device according to claim 1 wherein the device is operable to transform the input signal from the first frequency to a second frequency higher than the first frequency and wherein the oscillation signals are at the second frequency.
10. The device according to claim 1 wherein N equals 8 and the duty cycle of each of the oscillation signals is 12.5%.
11. The device according to claim 1 wherein N equals 6 and the duty cycle of each of the oscillation signals is 16.67%.
12. The device according to claim 1 wherein the first frequency comprises a baseband frequency.
13. The device according to claim 1 wherein N comprises an even number.
14. A method of frequency transformation comprising
providing a plurality N of first signals at a first frequency from an input signal having an in-phase component I and a quadrature signal component Q;
generating N parallel oscillation signals, wherein the N oscillation signals are stepped in phase with respect to one another;
mixing each first signal with a respective oscillation signal to provide an output signal; and
amplifying the N output signals from the N mixing components in N sequential phases for transmission.
15. The method according to claim 14 wherein mixing each first signal with a respective oscillation signal comprises controlling a switching arrangement receiving one of the first signals by the respective oscillator signal to provide the corresponding first signal to the common amplifier.
16. The method according to claim 15 , wherein N is a multiple of 8; and the N first signals comprise a set of 8 signals comprising I−Q; √2×I; I+Q; √2×Q; −I+Q; −√2×I; −I−Q; and −√2×Q signals.
17. The method according to claim 16 wherein the switching arrangements are operable to supply the first signals to the common amplifier in the following sequential or reversed sequential order: I−Q; √2×I; I+Q; √2×Q; −I+Q; −√2×I; −I−Q; and −√2×Q.
18. The method according to claim 15 , wherein N is a multiple of 6; and the N first signals comprise a set of 6 signals comprising I−Q; 2×I+Q; I+2×Q; −I+Q; −2×I−Q; and −I−2×Q signals.
19. The method according to claim 18 wherein the switching arrangements are operable to supply the first signals to the common amplifier in the following sequential or reversed sequential order: I−Q; 2×I+Q; I+2×Q; −I+Q; −2×I−Q; and −I−2×Q.
20. The method according to claim 14 wherein the first frequency comprises a baseband frequency.
21. The method according to claim 14 wherein N comprises an even number.
22. A computer program product stored in a non-transitory computer readable medium for controlling a data-processing device, the computer program product comprising a set of instructions which, when loaded into the data-processing device, causes the device to:
provide a plurality N of first signals at a first frequency from an input signal having an in-phase component I and a quadrature signal component Q;
generate N parallel oscillation signals, wherein the N oscillation signals are stepped in phase with respect to one another;
mix each first signal with a respective oscillation signal to provide an output signal; and
amplify the N output signals from the N mixing components in N sequential phases for transmission.
23. A transmitter comprising a frequency conversion device for transforming a frequency of an input signal, the frequency conversion device comprising:
a signal generator for providing a plurality N of first signals at a first frequency from an input signal having an in-phase component I and a quadrature signal component Q;
an oscillator for generating N parallel oscillation signals, wherein the N oscillation signals are stepped in phase with respect to one another;
a mixer comprising N mixing components, each mixing component being coupled to receive a respective one of the plurality of first signals and coupled to receive a respective oscillation signal for mixing the respective first signal with the corresponding oscillation signal to provide an output signal; and
a common amplifier for receiving the N output signals from the N mixing components in N sequential phases for transmission.