Detection of lightning

1. A lightning detector comprising:

a Digital Radio Mondiale (DRM) digital broadcasting system receiver having an analog front-end and a digital base-band;

wherein with the analog front-end DRM receiver the radio signal from lightning can be detected when a DRM receiver application and a lightning detection application operate in the same AM band application engine; and

wherein a DRM receiver comprises an I/Q demodulator; wherein the in-phase and the quadrature branches of an I/Q demodulator based receiver are configured to be used in different modes.

2. A lightning detector according to claim 1 , wherein a combined AM DRM broadcast receiver and lightning detector is integrated to a mobile RF device.

3. A lightning detector according to claim 2 , wherein the mobile RF device is a mobile telecommunication terminal.

4. A lightning detector according to claim 1 , wherein the DRM receiver is configured to use the analog front-end, a digital hardware accelerator and a processor, and the lightning detector is configured to use the analog front-end and an application software compatible with the processor.

5. A lightning detector according to claim 1 , wherein the in-phase and quadrature branches of the I/Q demodulator based receiver are configured to process different frequency bands of the AM frequency range.

6. A lightning detector according to claim 1 , wherein the DRM analog front-end has a homodyne topology.

7. A lightning detector according to claim 1 , wherein the DRM receiver is a triggering device for another lightning indicator.

8. A method comprising:

a Digital Radio Mondiale (DRM) digital broadcasting system receiver having an analog front-end and a digital base-band;

wherein with the analog front-end DRM receiver the radio signal from lightning is detected while the DRM receiver and a lightning detection application both operate in the same AM band application engine; and

wherein a lightning detection AM band radio signal which is bypassing a DRM receiver's hardware accelerator is handled by application specific software running in the processor.

9. A method according to claim 8 , wherein the DRM receiver uses the analog front-end, a digital hardware acceleration and a processor and that the lightning detector uses the analog front-end and the application running in said processor.

10. A method according to claim 9 , wherein those applications are performed at the same time.

11. A method according to claim 8 , wherein the DRM receiver operates as a triggering device for another lightning indicator.

12. A lightning detector comprising:

a Digital Radio Mondiale (DRM) digital broadcasting system receiver having an analog front-end and a digital base-band;

wherein with the analog front-end DRM receiver the radio signal from lightning can be detected when a DRM receiver application and a lightning detection application operate in the same AM band application engine; and

wherein a DRM receiver analog stage comprises an antenna, an input image preventing Low Pass filter, a low noise amplifier (LNA), the gain of which LNA can be adjusted, a RF mixer to downconvert the input signal with the help of a first local oscillator (LO) frequency, in order to selectively pass the selected channel through a channel filter and via an automatic gain controlling stage to I/Q mixers controlled by a second LO with quadrature outputs.

13. A method comprising:

a Digital Radio Mondiale (DRM) digital broadcasting system receiver having an analog front-end and a digital base-band;

wherein with the analog front-end DRM receiver the radio signal from lightning is detected while the DRM receiver and a lightning detection application both operate in the same AM band application engine; and

wherein the DRM receiver analog stage comprises an antenna, an input image preventing low pass filter, a low noise amplifier (LNA), the gain of which LNA can be adjusted, a RF mixer to downconvert the input signal with the help of a first local oscillator (LO) frequency, in order to selectively pass the selected channel through a channel filter and via an automatic gain controlling stage to I/Q mixers, controlled by a second LO with quadrature outputs.

14. A lightning detector according to claim 13 , wherein by dividing the LO frequency for a demodulator mixer in one branch that branch can be used for lightning detection purposes on a frequency other than the DRM frequencies.

15. A lightning detector comprising:

a Digital Radio Mondiale (DRM) digital broadcasting system receiver having an analog front-end and a digital base-band;

wherein with the analog front-end DRM receiver the radio signal from lightning can be detected when a DRM receiver application and a lightning detection application operate in the same AM band application engine; and

wherein one of the desired frequency bands is base-band, and it comprises an antenna, a band pass filter, a low noise amplifier and the inphase and quadrature mixers that are clocked by a local oscillator having quadrature outputs.

16. A lightning detector according to claim 15 , wherein the I branch respective the Q branch of the demodulator are configured to be used on different frequency bands.

17. A lightning detector according to claim 15 , wherein when one branch is in use for lightning detection, the other branch can be used for additional base -band lightning detection without downconversion by the mixer by arranging a bypass switch for this purpose.

18. A method comprising:

a Digital Radio Mondiale (DRM) digital broadcasting system receiver having an analog front-end and a digital base-band;

wherein with the analog front-end DRM receiver the radio signal from lightning is detected while the DRM receiver and a lightning detection application both operate in the same AM band application engine; and

wherein one of the desired frequency bands is base-band, and that the method comprises the use of an antenna, a band pass filter, a low noise amplifier and the inphase and quadrature mixers of a I/Q demodulator clocked by a local oscillator.

19. A method according to claim 18 , a divider is arranged to divide the local oscillator frequency that clocks one mixer of said I/Q demodulator.

20. A method according to claim 19 , wherein the demodulator I/Q branches are used for different frequency bands.

21. A method according to claim 18 , wherein the demodulator I/Q branches can be adjusted to use different path gain.

22. A method according to claim 18 , wherein the demodulator I/Q branches can be adjusted to use different path filtering.

23. A method according to claim 18 , wherein when one demodulator branch is in use for lightning detection, the other branch is used for additional base-band lightning detection without downconversion by arranging a mixer bypass switch for this purpose.

24. A method according to claim 23 , wherein for base-band lightning detection a separate low frequency inductive antenna is used and after optional filtering by a low pass filter the received base-band signal is directly fed using the said mixer bypass switch to the input of one branch of the I/Q demodulator and the output after analog to digital conversion to a processor.