Analog signal recording system
One embodiment of the present invention provides a signal-recording system. During operation, the system receives a wideband multi-channel radio frequency (RF) signal, which includes a plurality of single-channel RF signals modulated at different carrier frequencies. The system down-converts the received wideband multi-channel RF signal to baseband, and records the down-converted signal.
1. A method for simultaneously recording television signals from multiple television channels, comprising:
receiving a wideband multi-channel radio frequency (RF) signal, which includes the television signals from the multiple television channels; and
simultaneously recording the television signals from the multiple television channels, wherein the simultaneous recording involves:
using a single quadrature demodulator to down-convert the received wideband multi-channel RF signal, which includes the television signals from the multiple television channels, to baseband; and
directly recording the down-converted baseband signal without any further processing of the down-converted baseband signal.
2. The method of claim 1 , further comprising:
up-converting, using a single quadrature modulator, the recorded baseband signal to an original RF band to obtain the original television signals from the multiple television channels; and
receiving the up-converted signal, thereby enabling a replay of a single-channel TV signal.
3. The method of claim 1 , wherein the wideband multi-channel RF signal includes one of:
a broadcast TV signal;
a cable TV signal;
a satellite TV signal;
a broadcast radio signal;
a WiFi signal; and
a mobile phone signal.
4. The method of claim 3 , wherein the broadcast TV signal covers an entire ultra high frequency (UHF) TV band.
5. The method of claim 1 , wherein recording the down-converted baseband signal involves recording the down-converted baseband signal in an analog form as an analog baseband signal.
6. The method of claim 5 , wherein recording the down-converted signal in the analog form is performed by a recorder based on magnetic tapes.
7. The method of claim 1 , wherein the wideband multi-channel RF signal has a bandwidth that exceeds 400 MHz.
8. A system for simultaneously recording television signals from multiple television channels, comprising:
a receiving mechanism configured to receive a wideband multi-channel radio frequency (RF) signal, which includes the television signals from the multiple television channels; and
a television-signal recorder configured to simultaneously record the television signals from the multiple television channels,
wherein while simultaneous recording the television signals the television-signal recorder is configured to:
use a single quadrature demodulator to down-convert the received wideband multi-channel RF signal, which includes the television signals from the multiple television channels, to baseband; and
directly record the down-converted baseband signal without any further processing of the down-converted baseband signal.
9. The system of claim 8 , further comprising a TV-signal re-player configured to replay the recorded television signals, wherein while replaying the recorded television signals, the TV signal re-player is configured to:
use a single quadrature modulator to up-convert the recorded signal to an original RF band to obtain the original television signals from the multiple television channels; and
replay a single-channel TV signal.
10. The system of claim 8 , wherein the wideband multi-channel RF signal includes one of:
a broadcast TV signal;
a cable TV signal;
a satellite TV signal;
a broadcast radio signal; and
a mobile phone signal.
11. The system of claim 10 , wherein the broadcast TV signal covers an entire ultra high frequency (UHF) TV band.
12. The system of claim 8 , wherein the television-signal recorder further comprises an analog signal-recorder configured to record the down-converted baseband signal as an analog baseband signal.
13. The system of claim 12 , wherein the analog signal-recorder includes a magnetic tape recorder.
14. The system of claim 8 , wherein the wideband multi-channel RF signal has a bandwidth that exceeds 400 MHz.