Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents that may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of the present invention, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be readily apparent to one skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail so as not to unnecessarily obscure aspects of the present invention.
For convenience and simplicity, the terms “data,” “signal,” and “signals” may be used interchangeably, as may the terms “connected to,” “coupled with,” “coupled to,” and “in communication with” (which terms also refer to direct and/or indirect relationships between the connected, coupled and/or communication elements unless the context of the term's use unambiguously indicates otherwise), but these terms are also generally given their art-recognized meanings. Also, for convenience and simplicity, the terms “computing,” “calculating,” “determining,” “processing,” “manipulating,” “transforming,” “operating,” “displaying,” and “setting” (or the like) may be used interchangeably, and generally refer to the action and processes of a computer, data processing system, logic circuit or similar processing device (e.g., an electrical, optical, or quantum computing or processing device), that manipulates and transforms data represented as physical (e.g., electronic) quantities. The terms refer to actions, operations and/or processes of the processing devices that manipulate or transform physical quantities within the component(s) of a system or architecture (e.g., registers, memories, other such information storage, transmission or display devices, etc.) into other data similarly represented as physical quantities within other components of the same or a different system or architecture.
The present invention concerns apparatuses, circuits, and methods for receiving at least one radio signal in a radio controlled timing apparatus with a single clock source. In one aspect of the invention, the radio controlled timing apparatus can include: a radio receiver configured to (i) receive a local carrier signal derived from a reference timing signal and at least one modulated time code signal and (ii) generate a time code signal from the local carrier signal and at least one modulated time code signal; a decoder configured to (i) receive the time code signal and (ii) generate a time setting and/or correction signal therefrom; and a timing mechanism configured to receive (i) a real-time signal derived from the reference timing signal and (ii) the time setting and/or correction signal.
A further aspect of the invention concerns a circuit for a radio controlled timing apparatus that can include: a reference timing signal source; a frequency synthesizer configured to (i) receive a reference timing signal and a selectable frequency control signal and (ii) generate a local carrier signal from the reference timing signal and the selectable frequency control signal; a radio receiver configured to (i) receive the local carrier signal and at least one modulated time code signal and (ii) generate a time code signal from the local carrier signal and at least one modulated time code signal; and a decoder configured to (i) receive the time code signal and (ii) generate a time setting and/or correction signal therefrom.
A further aspect of the invention concerns a circuit for a radio controlled timing apparatus that can include: a frequency synthesizer configured to (i) receive a reference timing signal and a selectable frequency control signal and (ii) generate a local carrier signal from the reference timing signal and the selectable frequency control signal; and a radio receiver configured to (i) receive the local carrier signal and at least one modulated time code signal and (ii) generate a time code signal from the local carrier signal and at least one modulated time code signal.
A further aspect of the present invention concerns a method of synchronizing a radio controlled timing apparatus that can include: multiplying and/or dividing a reference timing signal by a first ratio to generate a real-time signal; multiplying and/or dividing the reference timing signal by a second ratio to generate a local carrier signal; generating a time code signal from the local carrier signal and at least one modulated time code signal; and decoding the time code signal to generate a time setting and/or correction signal.
The invention, in its various aspects, will be explained in greater detail below with regard to exemplary embodiments.
An Exemplary Radio Controlled Timing Apparatus
In one embodiment, an exemplary radio controlled timing apparatus includes: a radio receiver configured to (i) receive a local carrier signal derived from a reference timing signal and at least one modulated time code signal and (ii) generate a time code signal from the local carrier signal and at least one modulated time code signal; a decoder configured to (i) receive the time code signal and (ii) generate a time setting and/or correction signal therefrom; and a timing mechanism configured to receive (i) a real-time signal derived from the reference timing signal and (ii) the time setting and/or correction signal.
Referring now to
In one implementation, the radio controlled timing apparatus may include a real-time signal generator 220 which receives the reference timing signal 213 and generates the real-time signal 221. The real-time signal generator 220 may include one or more multipliers and/or dividers, and the configuration of such real-time signal generators are well known to those skilled in the art.
In a further implementation, the radio controlled timing apparatus may include a frequency synthesizer 280 configured to receive the reference timing signal 214 and generate a local carrier signal 285. The frequency synthesizer 280 may include an integer or fractional-N (or “fractal-N”, as it is sometimes known) type phase locked loop and at least one divider. Frequency synthesizers comprising such a phase locked loop and a frequency divider are conventional, and their design, implementation, and operation are well known to those skilled in the art. An example of a frequency synthesizer comprising an integer type phase locked loop and a frequency divider is shown in
Referring to
The divider ratios within the frequency dividers 381, 387, 388 are controlled by the status of a selectable frequency control signal 370. The selectable frequency control signal 370 may be a digital multi-bit signal of n bits, where 2n is the number of configurable states of the frequency synthesizer (e.g., the number of possible local carrier frequencies to be produced). The number of configurable states of the frequency synthesizer may directly relate to the number of broadcast time code signal frequencies that the radio controlled timing apparatus is configured to receive. The selectable frequency control signal 370 is decoded by control signal logic 371 to produce control signals P 372, Q 373, and R 374 which determine the divider ratios of the respective frequency dividers 381, 387, 388. Each control signal P, Q, or R may also be a digital multi-bit signal. For example, if the frequency divider 381 requires 8 configurable states, P may be a three-bit signal. The exemplary frequency synthesizer is thus programmable and can generate one or more local carrier signals with the same or different frequencies. Also, a single local carrier signal (e.g., 285) can have one of a plurality of frequencies.
In one implementation, and referring back to
Furthermore, the implementation and configuration of frequency dividers 381, 387, 388 as shown in
In yet another implementation, the radio controlled timing apparatus as shown in
The radio receiver/time code decoder 260 may consist of separate functional elements. As shown in
An Exemplary Circuit for a Radio Controlled Timing Apparatus
In another embodiment, a circuit for a radio controlled timing apparatus can include: a reference timing signal source; a frequency synthesizer configured to (i) receive a reference timing signal and a selectable frequency control signal and (ii) generate a local carrier signal from the reference timing signal and the selectable frequency control signal; a radio receiver configured to (i) receive the local carrier signal and at least one modulated time code signal and (ii) generate a time code signal from the local carrier signal and at least one modulated time code signal; and a decoder configured to (i) receive the time code signal and (ii) generate a time setting and/or correction signal therefrom.
Referring now to
In yet another implementation, and as shown in
In a further implementation, and referring back now to
In another implementation, the radio controlled timing apparatus may include a real-time signal generator. Referring back to
In a further implementation, the frequency synthesizer 280 may include an integer or fractional-N type phase locked loop and at least one divider. Frequency synthesizers comprising such a phase locked loop and frequency divider are conventional, and their design, implementation, and operation are well known to those skilled in the art. An example of a frequency synthesizer comprising an integer type phase locked loop and a frequency divider is shown in
Another Exemplary Circuit for a Radio Controlled Timing Apparatus
In yet another embodiment, a circuit for a radio controlled timing apparatus that can include: a frequency synthesizer configured to (i) receive a reference timing signal and a selectable frequency control signal and (ii) generate a local carrier signal from the reference timing signal and the selectable frequency control signal; and a radio receiver configured to (i) receive the local carrier signal and at least one modulated time code signal and (ii) generate a time code signal from the local carrier signal and at least one modulated time code signal.
Referring now to
In another implementation, the circuit may include at least one RF amplifier to amplify at least one broadcast time code signal. As discussed above and shown in
In yet another implementation, the circuit may include a reference timing signal source. As shown in
An Exemplary Method of Synchronizing a Radio Controlled Timing Apparatus
In a further embodiment, a method of synchronizing a radio controlled timing apparatus can include: multiplying and/or dividing a reference timing signal by a first ratio to generate a real-time signal; multiplying and/or dividing the reference timing signal by a second ratio to generate a local carrier signal; generating a time code signal from the local carrier signal and at least one modulated time code signal; and decoding the time code signal to generate a time setting and/or correction signal. Typically, the time code signal contains at least the current time, however the time code signal may also contain: the date; daylight savings time and leap year indicators; parity information; and/or other information.
In one implementation, the method of generating a time code signal may include: receiving a modulated time code signal; and, demodulating the modulated time code signal with the local carrier. In another implementation, the method may also include adjusting the real-time signal in accordance with the time setting and/or correction signal so as to synchronize the radio controlled timing apparatus with a broadcast time code signal.
In yet another implementation, the method may also include displaying a representation of the real-time signal. The representation may be displayed in a traditional analog form (movable time hands) or in a digital display element, such as a liquid crystal display (LCD).
The frequency of the generated local carrier signal may correspond to the state of a selectable frequency control signal. The state of the selectable frequency control signal may be selected by a simple user interface, such as an external switch or button. Alternatively, the selectable frequency control signal may be configured within the radio controlled timing apparatus by a logic element. One method of configuring the selectable frequency control signal within the logic element may include the steps of: selecting a first state of the selectable frequency control signal corresponding to a first desired broadcast radio station; determining whether a valid time code signal was received; and if a valid time code signal was not received, selecting a second state of the selectable frequency control signal which corresponds to a second desired broadcast radio station and likewise determining whether a valid time code signal was received. The process may repeat, sequentially, selecting each state of the selectable frequency control signal corresponding to each broadcast radio station that to be received.
Thus, the present invention provides apparatuses, circuits, and methods which can enable a radio controlled clock to receive radio signals at any of a plurality of frequencies using a single quartz crystal.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.