Sliding intermediate frequency (IF) receiver with adjustable division ratio and sliding IF reception method

1. A sliding intermediate frequency (IF) reception method, comprising:

generating a first local oscillation signal and a second local oscillation signal, based on a division ratio determined in advance of a frequency of the first local oscillation signal to a frequency of the second local oscillation signal, wherein the generating of the first local oscillation signal and the second local oscillation signal comprises

increasing the division ratio when a first image rejection ratio (IRR) of a first IF signal is equal to or greater than a first threshold, and

decreasing the division ratio when a second IRR of a second IF signal is equal to or greater than a second threshold;

converting a received input signal to the first IF signal, based on the first local oscillation signal; and

converting the first IF signal to the second IF signal, based on the second local oscillation signal.

2. The sliding IF reception method of claim 1 , wherein the generating of the first local oscillation signal and the second local oscillation signal further comprises:

determining the division ratio so that an amount of power to be consumed by a sliding IF receiver is less than a threshold power.

3. The sliding IF reception method of claim 1 , wherein the generating of the first local oscillation signal and the second local oscillation signal further comprises:

initializing the division ratio prior to increasing or decreasing the division ratio.

4. The sliding IF reception method of claim 1 , wherein the generating of the first local oscillation signal and the second local oscillation signal further comprises:

determining the division ratio so that an error rate of a signal obtained by processing the received input signal is less than a threshold error rate.

5. The sliding IF reception method of claim 1 , wherein the generating of the first local oscillation signal and the second local oscillation signal further comprises:

measuring error rates for each value of the division ratio while increasing the division ratio sequentially from a first value to a second value; and

determining, as the division ratio, a value corresponding to a minimum error rate among the measured error rates.

6. The sliding IF reception method of claim 1 , wherein the generating of the first local oscillation signal and the second local oscillation signal further comprises:

detecting an interference signal; and

determining the division ratio, based on the interference signal.

7. A sliding intermediate frequency (IF) reception method, comprising:

generating a first local oscillation signal and a second local oscillation signal, based on a division ratio determined in advance of a frequency of the first local oscillation signal to a frequency of the second local oscillation signal, wherein the generating of the first local oscillation signal and the second local oscillation signal comprises

increasing the division ratio when a magnitude of a first image signal included in a signal obtained by filtering a first IF signal is greater than a carrier-to-noise ratio (CNR), and

decreasing the division ratio when a magnitude of a second image signal included in a signal obtained by filtering a second IF signal is greater than the CNR;

converting a received input signal to the first IF signal, based on the first local oscillation signal; and

converting the first IF signal to the second IF signal, based on the second local oscillation signal.

8. The sliding IF reception method of claim 1 , wherein the generating of the first local oscillation signal and the second local oscillation signal further comprises:

dividing the first local oscillation signal at the division ratio, to generate the second local oscillation signal.

9. The sliding IF reception method of claim 1 , wherein the converting of the received input signal to the first IF signal comprises:

performing filtering on the received input signal in a band; and

converting the filtered received input signal to the first IF signal.

10. The sliding IF reception method of claim 1 , wherein the converting of the first IF signal to the second IF signal comprises:

performing filtering on the second IF signal in a base band (BB).

11. A sliding intermediate frequency (IF) receiver, comprising:

an oscillator configured to generate a first local oscillation signal and a second local oscillation signal, based on a division ratio determined in advance of a frequency of the first local oscillation signal to a frequency of the second local oscillation signal;

a first frequency converter configured to convert a received input signal to a first IF signal, based on the first local oscillation signal;

a second frequency converter configured to convert the first IF signal to a second IF signal, based on the second local oscillation signal; and

an oscillation controller configured to increase the division ratio when a first image rejection ratio (IRR) of the first IF signal is equal to or greater than a first threshold, and to decrease the division ratio when a second IRR of the second IF signal is equal to or greater than a second threshold.

12. The sliding IF receiver of claim 11 ,

wherein the oscillation controller is further configured to determine the division ratio so that an amount of power to be consumed in the sliding IF receiver is less than a threshold power.

13. The sliding IF receiver of claim 11 ,

wherein the oscillation controller is further configured to initialize the division ratio prior to increasing or decreasing the division ratio.

14. The sliding IF receiver of claim 11 ,

wherein the oscillation controller is further configured to determine the division ratio so that an error rate of a signal obtained by processing the received input signal is less than a threshold error rate.

15. The sliding IF receiver of claim 11 ,

wherein the oscillation controller is further configured to measure error rates for each value of the division ratio while increasing the division ratio sequentially from a first value to a second value, and to determine, as the division ratio, a value corresponding to a minimum error rate among the measured error rates.

16. The sliding IF receiver of claim 11 ,

an interference detector configured to detect an interference signal; and

wherein the oscillation controller is further configured to determine the division ratio based on the interference signal.

17. The sliding IF receiver of claim 11 ,

wherein the oscillation controller is further configured to increase the division ratio when a magnitude of a first image signal included in a signal obtained by filtering the first IF signal is greater than a carrier-to-noise ratio (CNR), and to decrease the division ratio when a magnitude of a second image signal included in a signal obtained by filtering the second IF signal is greater than the CNR.

18. The sliding IF receiver of claim 11 , wherein the oscillator comprises a divider configured to divide the first local oscillation signal at the division ratio, to generate the second local oscillation signal.

19. The sliding IF receiver of claim 11 , further comprising:

a first filter configured to perform filtering on the received input signal in a band; and

a second filter configured to perform filtering on the second IF signal in a base band (BB).

20. The sliding IF receiver of claim 11 , wherein the second frequency converter comprises:

an in-phase converter configured to convert the first IF signal to an in-phase signal; and

a quadrature converter configured to convert the first IF signal to a quadrature signal, and

wherein the second IF signal comprises the in-phase signal and the quadrature signal.