LOCAL WIRELESS SIGNAL TRANSMITTING/RECEIVING APAPRATUS AND METHOD USING DIGITAL RADIO FREQUENCY PROCESSING TECHNOLOGY

• US 20110075763A1
• Filed: 05/19/2009
• Published: 03/31/2011
• Est. Priority Date: 05/29/2008
• Status: Active Grant

• Current Assignee: SK Telecom Co., Ltd.
• Original Assignee: SK Telecom Co., Ltd.
• Inventors: Oh, Se Hyun, Hong, Sung Cheol, Kim, Young Woo, Yu, Jae Hwang, Shim, Woo Jin
• Granted Patent: US 8,755,461 B2
• Time in Patent Office: Days
• US Class Current: 375/309
• CPC Class Codes: H04L 27/2032 for discrete phase modulation, e.g. in which the phase of the carrier is modulated in a nominally instantaneous manner
• CPC Class Codes: H04L 27/223 Demodulation in the optical domain optical demodulation H04B10/676
• CPC Class Codes: H04L 27/361 Modulation using a single or unspecified number of carriers, e.g. with separate stages of phase and amplitude modulation

Abstract

A local wireless signal transmitting/receiving apparatus and method using digital RF processing technology. When the local wireless signal transmitting/receiving apparatus generates a local wireless signal to be transmitted, spreads the frequency of the generated local wireless signal and thereby generates a baseband signal, the local wireless signal transmitting/receiving apparatus converts the baseband signal of the local wireless signal into phase information, converts the phase information into an RF signal by means of a polar modulator, and transmits the RF signal.

Claims

1. A local wireless signal transmitting apparatus using digital RF processing technology, comprising:

a phase converter converting a sinusoidal pulse offset QPSK signal into Minimum Shift keying (MSK) phase information, wherein the MSK phase information is a MSK signal; and

a digital RF processor directly converting the MSK phase information into an RF signal through polar modulation, power-amplifying the RF signal and transmitting the power-amplified RF signal.

2. The local wireless signal transmitting apparatus of claim 1, wherein the sinusoidal pulse offset QPSK signal is a Zigbee signal.

3. The local wireless signal transmitting apparatus of claim 1, wherein the power amplification is performed using a switching mode power amplifier.

4. The local wireless signal transmitting apparatus of claim 1, wherein the digital RF processor comprises a polar modulator, a digitally controlled oscillator (DCO) and a digitally controlled power amplifier (DPA), the polar modulator receives the MSK phase information from the phase converter and modulates the phase of the DCO to generate an RF signal, and the RF signal is applied to the DPA and power-amplified.

5. The local wireless signal transmitting apparatus of claim 4, wherein parts of the RF signal generated by modulating the phase of the DCO by the polar modulator are applied to a time-to-digital converter and fed back to the polar modulator.

6. The local wireless signal transmitting apparatus of claim 4, wherein the DPA is a switching mode power amplifier.

7. The local wireless signal transmitting apparatus of claim 4, wherein the phase of the DCO is controlled by tuning digitally controlled low-capacity capacitors.

8. The local wireless signal transmitting apparatus of claim 4, wherein the MSK phase information is modulated through sigma-delta modulation.

9. The local wireless signal transmitting apparatus of claim 1, wherein the digital RF processor comprises a polar modulator, a DCO and a DPA, the polar modulator receives the MSK phase information from the phase converter and modulates the phase of the DCO to generate an RF signal, and the RF signal is applied to the DPA and power-amplified, an amplitude control signal of the polar modulator controlling the output power of the DPA.

10. The local wireless signal transmitting apparatus of claim 9, wherein the output power of the DPA is controlled in the first chip period and a chip extension period of a chip sequence.

11. The local wireless signal transmitting apparatus of claim 10, wherein the output power of the DPA is controlled with sinusoidal weighting.

12. The local wireless signal transmitting apparatus of claim 9, wherein parts of the RF signal generated by modulating the phase of the DCO by the polar modulator are applied to a time-to-digital converter and fed back to the polar modulator.

13. The local wireless signal transmitting apparatus of claim 9, wherein the DPA is a switching mode power amplifier.

14. The local wireless signal transmitting apparatus of claim 9, wherein the phase of the DCO is controlled by tuning digitally controlled low-capacity capacitors.

15. The local wireless signal transmitting apparatus of claim 9, wherein the MSK phase information is modulated through sigma-delta modulation.

16. A local wireless signal transmitting method using digital RF processing technology, comprising:

a step in which a local wireless signal transmitting apparatus generates a sinusoidal pulse offset QPSK signal and converts the sinusoidal pulse offset QPSK signal into MSK phase information; and

a step in which the local wireless signal transmitting apparatus directly converts the MSK phase information into an RF signal through polar modulation, power-amplifies the RF signal and transmits the amplified RF signal.

17. A local wireless signal receiving apparatus using digital RF processing technology, comprising:

a receiving digital RF processor receiving an external RF signal and detecting an IF signal from the RF signal;

a zero-crossing signal detector detecting a zero-crossing signal from the IF signal received from the receiving digital RF processor, and converting the zero-crossing signal into a digital signal; and

a receiving signal processor converting the digital signal received from the zero-crossing signal detector into a processable local wireless signal.

18. The local wireless signal receiving apparatus of claim 17, wherein the zero-crossing signal detector is one of a selecting zero-crossing signal detector or an averaging zero-crossing signal detector.

19. The local wireless signal receiving apparatus of claim 17, wherein the IF signal is a single bit.

20. The local wireless signal receiving apparatus of claim 17, wherein the receiving digital RF processor filters the RF signal to remove a first decimation factor from the RF signal and detects the IF signal from the RF signal.

21. The local wireless signal receiving apparatus of claim 20, wherein the receiving digital RF processor filters the IF signal to remove a second decimation factor, filters the filtered IF signal to remove a third decimation factor, and then detects the domain of the IF signal.

22. The local wireless signal receiving apparatus of claim 21, wherein when the domains of IF signals are received from the receiving digital RF processor, the zero-crossing signal detector detects a time difference between the domains of the IF signals to detect the zero-crossing signal and converts the zero-crossing signal into a digital signal.

23. The local wireless signal receiving apparatus of claim 22, wherein the receiving signal processor converts the digital signal received from the zero-crossing signal detector into the local wireless signal and outputs the local wireless signal to a physical protocol data unit (PPDU).

24. A local wireless signal receiving method using digital RF processing technology, comprising:

a step in which a local wireless signal receiving apparatus detects an IF signal from an external RF signal;

a step in which the local wireless signal receiving apparatus detects a zero-crossing signal from the IF signal and converts the zero-crossing signal into a digital signal; and

a step in which the local wireless signal receiving apparatus converts the digital signal into a processable local wireless signal.