1. An integrated circuit for use in a mobile TV receiver, the integrated circuit comprising:
one or more input stages for receiving respective RF signals, including mobile TV signals;
a first signal processing path for performing low IF demodulation of the RF signals;
a second signal processing path for performing IQ demodulation of the RF signals;
a control unit arranged to selectively connect the one or more input stages to the first signal processing path or to the second signal processing path; and
output circuitry connected to the first and second signal processing paths, wherein the control unit is arranged to determine whether the output circuitry outputs signals that have been obtained from the one or more RF signals by IF demodulation or alternatively by IQ demodulation.
2. The integrated circuit according to claim 1 in which the one or more input stages each include a filter for removing frequencies received that are not mobile TV signals or that are generated by the mobile TV receiver device.
3. The integrated circuit according to claim 1 in which the control unit is operative to disable at least one section of the integrated circuit, to reduce the power consumption of that section.
4. The integrated circuit according to claim 3 in which the control unit is operative to disable selectively the first or second processing paths.
5. The integrated circuit according to claim 3 in which the control unit is operative to disable one or more of the input stages.
6. The integrated circuit according to claim 3 in which the control unit disables the section by setting a pin connected to the section to ground voltage.
7. The integrated circuit according to claim 6 in which the control unit, together with disabling the section, also turns off a circuit for delivering power to the section.
8. The integrated circuit according to claim 3 in which the control unit is operative based on a clock signal to turn at least one section of the integrated circuit on or off according to a timing present in the RF signal.
9. The integrated circuit according to claim 3 in which the control unit is operative to modify the operation of at least one other component of the integrated circuit selectively between a first operation state with higher power consumption and a second operation state of lower power consumption.
10. An integrated circuit according to claim 1 comprising at least two automatic gain control circuits, a first wideband automatic gain control circuit operative to control the gain of the input stages, and a second narrowband automatic gain control circuit operative to control the amplitude of the output of the output circuitry.
11. The integrated circuit according to claim 1 further comprising a phase-lock loop unit, a crystal oscillator, and oscillating signal transmission circuitry for transmitting an oscillating signal generated using the crystal oscillator out of the integrated circuit.
12. The integrated circuit according to claim 1 further comprising a phase-lock loop unit and oscillating signal receiver for receiving a crystal oscillation signal input for driving the phase-lock loop unit.
13. The integrated circuit according to claim 1 further comprising a phase-lock loop unit, a crystal oscillator, oscillating signal receiver for receiving a crystal oscillation signal input for driving the phase-lock loop unit, and oscillating signal transmission circuitry for transmitting an oscillating signal generated using the crystal oscillator out of the integrated circuit, and control circuitry for selecting whether the phase-lock loop unit is driven based on a crystal oscillation signal input.
14. The integrated circuit according to claim 11 in which the crystal oscillator generates a signal in the range of about 1 to 60 MHz.
15. The integrated circuit according to claim 14 in which the crystal oscillator generates a signal of at least 16 MHz.
16. The integrated circuit according to claim 1 in which the input stages each comprise a variable amplifier or a phase and time delay variation unit.
17. A mobile TV receiver device comprising:
one or more input stages for receiving respective RF signals, including mobile TV signals;
a first signal processing path for performing low IF demodulation of the RF signals;
a second signal processing path for performing IQ demodulation of the RF signals;
a control unit arranged to selectively connect the one or more input stages to the first signal processing path or to the second signal processing path;
output circuitry connected to the first and second signal processing paths, wherein the control unit is arranged to determine whether the output circuitry outputs signals that have been obtained from the one or more RF signals by IF demodulation or alternatively by IQ demodulation;
one or more antennas that generate one or more RF signals and transmit them to respective ones of the input stages of the integrated circuit,
a base-band processing unit that receives the output of the output circuitry of the integrated circuit, and performs base-band processing to produce TV signals; and
a screen that receives the TV signals and uses them to generate TV images.
18. The mobile TV receiver device according to claim 17 in which there are a plurality of antennas generating respective RF signals and transmitting them to respective ones of the input stages.
19. The mobile TV receiver device according to claim 17 further comprising:
partitioning circuitry for partitioning the RF signals from at least one of the antennas into multiple components, the components being respective frequency ranges; and
transmission circuitry for transmitting the components to respective ones of the input stages.
20. The mobile TV receiver device according to claim 17 in which at least one of the antennas includes at least two portions for receiving radio signals with different polarizations, and which includes transmission circuitry for transmitting the received radio signals to different respective ones of the input stages.
21. The mobile TV receiver device according to claim 17 further comprising circuitry for generating and transmitting RF signals of at least one transmission frequency, the receiver device including one or more filters for filtering out the transmission frequency from the RF signals received by the antennas.
22. The mobile device according to claim 21 wherein the one or more filters are located within the integrated circuit on each of the input stages.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. An imaging lens of fixed focal length formed of only two lens components, in order from the object side, as follows:
an aperture diaphragm;
a first lens component having positive refractive power, having a concave lens surface on the object side, and having at least one aspheric lens surface; and
a second lens component having positive refractive power and having at least one aspheric lens surface;
wherein the following conditions are satisfied:
f1f2<3.0CL2DL2>0.8
where
f1 is the focal length of said first lens component,
f2 is the focal length of said second lens component,
CL2 is the thickness of said second lens component, measured parallel to the optical axis, at a distance from the optical axis determined by the smaller maximum optically effective diameter in said imaging lens of the two lens surfaces of said second lens component, and
DL2 is the thickness of said second lens component at the optical axis of the imaging lens.
2. The imaging lens of claim 1, wherein:
said first lens component includes a first lens element; and
said second lens component includes a second lens element.
3. The imaging lens of claim 1, wherein:
said first lens component consists of a first lens element; and
said second lens component consists of a second lens element.
4. The imaging lens of claim 1, wherein:
said first lens component has a meniscus shape;
said second lens component has a meniscus shape with its convex lens surface on the object side; and
the concave lens surface of said second lens component is formed so that its negative refractive power increases as the distance from the optical axis of the imaging lens increases.
5. The imaging lens of claim 2, wherein:
said first lens component has a meniscus shape;
said second lens component has a meniscus shape with its convex lens surface on the object side; and
the concave lens surface of said second lens component is formed so that its negative refractive power increases as the distance from the optical axis of the imaging lens increases.
6. The imaging lens of claim 2, wherein:
said first lens element has a meniscus shape;
said second lens element has a meniscus shape with its convex lens surface on the object side; and
the concave lens surface of said second lens element is formed so that its negative refractive power increases as the distance from the optical axis of the imaging lens increases.
7. The imaging lens of claim 3, wherein:
said first lens element has a meniscus shape;
said second lens element has a meniscus shape with its convex lens surface on the object side; and
the concave lens surface of said second lens element is formed so that its negative refractive power increases as the distance from the optical axis of the imaging lens increases.