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This application is a divisional of and claims priority to U. Provisional Patent Application Ser. Provisional Patent Application No. The present invention relates to the field of communications, and more specifically to improving signal fidelity in a communication system by compensating for interference that occurs between two or more communication channels.
Examples of such systems include mobile phones, wireless data networks e. EMI can become a problem when high-speed circuitry is routed in close proximity to a radio receiver. Thus, EMI often degrades the signal fidelity of the victim signal and impairs the quality of the radio reception.
Exemplary sources of interference sources can include, among others, a high-speed bus carrying data from a processor to a high-resolution display and a high-speed bus carrying data from a camera imaging sensor to a processor. As an example, FIG. Increasing the data rate or bandwidth of each lane, conductor, or channel of the display and camera bussesis often desirable. Thus, improvements in the display or camera system e. In other words, improving reception of low-power signals or noisy signals provides another motivation to reduce or to otherwise address interference or crosstalk.
A weak radio signal might have less intensity than the noise level of the EMIfor example. Thus, it is desired to reduce the EMI to facilitate reception of weaker radio signals or to enable operating a mobile phone or other radio in a noisy environment. As discussed in more detail below, those flex cables can be adapted to comprise an exemplary embodiment of the present invention.
EMI can also become problematic when two or more radio services are operated on the same handset. In this situation, the transmitted signal for a first radio service may interfere with the received signal for a second radio service.
Consequently, a small fraction of the duobinary signaling pdf to word converter, transmitted signal can leak into the second, received signal as interference. A third source of EMI can be circuits or circuit elements located in close proximity to a victim channel or radio.
Like the signals on the high-speed buses, signals flowing through a circuit or circuit component can emit EMI One technique for actively addressing signal interference involves sampling the aggressor signal and processing the acquired sample to generate an emulation of the interference, in the form of a simulated or emulated interference signal.
A canceller circuit subtracts the emulated interference signal from the received victim signal corrupted by the interference to yield a compensated or corrected signal with reduced interference. Conventional technologies for obtaining a representative sample of the aggressor signal, or of the interference itself, are frequently inadequate. Sampling distortion or error can lead to a diminished match between the interference and the emulation of the interference.
One technique for obtaining a sample of the aggressor signal is to directly tap the aggressor line. However, the resulting loss of power on the transmitted aggressor line is detrimental in many applications, such as in handheld radios, cell phones, or handset applications.
Directly tapping into the aggressor line can also adversely impact system modularity. The interference duobinary signaling pdf to word converter system should usually be situated in close proximity to the source or sources of interference. This configuration helps the sampling system sample the interference signals while avoiding sampling the radio signal.
Inadvertent sampling of the radio signal could result in the canceller circuit removing the victim radio signal from the compensated signal, thereby degrading the compensated signal.
In other words, conventional technologies for obtaining an interference sample often impose awkward or unwieldy constraints on the location of the sampling duobinary signaling pdf to word converter. For handset applications, the sampling system should be compatible with the handset architecture and its compact configuration. Radio handsets, such as mobile phones, typically contain numerous components duobinary signaling pdf to word converter design engineers may struggle to integrate together using conventional technologies.
Strict placement requirements of conventional interference sampling systems frequently increase system design complexity. In other words, conventional interference sampling systems often fail to offer an adequate level of design flexibility as a result of positioning constraints. Another shortcoming of most conventional technologies for active EMI cancellation involves inadequate duobinary signaling pdf to word converter of power consumption. An active EMI cancellation system may consume an undesirably high level of electrical power that can shorten battery life in handset applications.
That is, EMI cancellation technology, when applied in a cellular telephone or another portable device, often draws too much electricity from the battery or consumes too much energy from whatever source of energy that the portable device uses.
Consumers typically view extended battery life as a desirable feature for a portable wireless communication product. Thus, reducing power consumption to extend usage time between battery recharges is often an engineering goal, mandate, or maxim. To address these representative duobinary signaling pdf to word converter in the art, what is needed is an improved capability for addressing, correcting, or canceling signal interference in communication systems.
Yet another need exists for a system that reduces or suppresses signal interference while managing power consumption. The present invention supports compensating for signal interference, such as EMI or crosstalk, occurring between two or more communication channels or between two or more communication elements in a communication system.
Compensating for interference can improve signal quality or enhance communication bandwidth or information carrying capability. A communication signal transmitted on one communication channel can couple an unwanted interference signal onto a second communication channel and interfere with communication signals transmitting on that second channel.
Either duobinary signaling pdf to word converter or each of the channels can comprise a transmission line, an electrical conductor or waveguide, a bus, a medium that provides a signal path, or an active or passive circuit element such as a filter, oscillator, diode, or amplifier not an exhaustive list. Thus, a channel can be a GSM device, a processor, a detector, a source, a diode, a circuit trace, duobinary signaling pdf to word converter a DSP chip, to name a few possibilities.
In addition to occurring between two channels, the interference effect can couple between and among three or more communication channels, with each channel imposing interference on two or more channels and receiving interference from two or more channels. A single physical medium, such as a single segment of wire, can provide a transmission medium for two or more channels, each communicating digital or analog information.
Alternatively, each channel can have a dedicated transmission medium. For example, a circuit board or flex cable can duobinary signaling pdf to word converter multiple conductors in the form of circuit traces, in which each trace provides a distinct communication channel. The sensor can comprise a sensing or sampling channel that obtains the sample. The sensing channel duobinary signaling pdf to word converter be, for example, a conductor dedicated to obtaining a representation of the aggressing signal or the interference.
That is, the sensing conductor can obtain a sample of the aggressor signal without necessarily physically contacting or directly touching the aggressor conductor, for example. In another aspect of the present invention, a circuit duobinary signaling pdf to word converter cancels, corrects, or compensates for or otherwise address communication interference can have at least two modes of operation. The interference compensation circuit could be coupled to the sensor, for example.
In the first mode, the interference compensation circuit can generate, produce, or duobinary signaling pdf to word converter a signal that, when applied to a communication signal, reduces interference associated with that communication signal.
In the second mode, the interference compensation circuit can refrain from producing or outputting the interference correction signal. The second mode can be viewed as a standby, idle, passive, sleep, or power-saving mode. Operating the interference compensation circuit in the second mode can offer a reduced level of power consumption.
The discussion of addressing interference presented in this summary is for illustrative purposes only. Various aspects of the present invention may be more clearly understood and appreciated from a review of the following detailed description duobinary signaling pdf to word converter the disclosed embodiments and by reference to the drawings and claims.
Many aspects of the invention can be better understood with reference to the above drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of exemplary embodiments of the present invention. Moreover, in the drawings, reference numerals designate corresponding, but not necessarily identical; parts throughout the different views. The present invention supports canceling, correcting, addressing, or compensating for interference, EMI, or crosstalk associated with one or more communication paths in a communication system, such as a high-speed digital data communication system duobinary signaling pdf to word converter a portable radio or a cellular telephone.
An interference sensor can obtain a signal representation or a sample of a communication signal that imposes interference or of the interference. The interference sensor can be integrated into a structure, such as a flex circuit or a circuit board, that supports or comprises at least one conductor that imposes or receives the interference.
In an exemplary embodiment, the interference sensor can be a dedicated conductor or circuit trace that is near an aggressor conductor, a victim conductor, or an EM field associated with the EMI. The sensor can be coupled to an interference compensation circuit. The interference compensation circuit can have at least two modes of operation.
In the first mode, the circuit can actively generate or output a correction signal. Turning to discuss each of the drawings presented in FIGS.
Referring now to FIGS. In an exemplary embodiment, a cellular telephone or some other portable wireless device can comprise the communication system A DSP chip connects to a display and a camera via two data busses duobinary signaling pdf to word converter, or channels.
As will be appreciated by those skilled in the art, the victim radio system handles communication signals in connection with transmission over a wireless network. In an exemplary embodiment, a flex circuitas illustrated in FIG. The flex circuit typically comprises a polymer, plastic, or dielectric film that is flexible and further comprises conductive circuit traces deposited on or adhering to the film substrate.
Conductors can be laminated between two pliable films, for example. The data busescan be embodied in one or more ribbon cables. The communication system comprises an interference compensation or correcting circuitdepicted in the exemplary form of an integrated circuit The interference compensation circuitdescribed in further detail below, delivers an interference compensation signal into or onto a channel that is a recipient of interference, to cancel or otherwise compensate for the received interference.
The interference compensation signal is derived or duobinary signaling pdf to word converter from a sample of an aggressor communication signal that is propagating on another channel, generating the crosstalk. The interference compensation circuit can be coupled between the channel duobinary signaling pdf to word converter, that generates the interference and the device that receives the interference In this configuration, the interference compensation circuit can sample or receive a portion of the signal that is causing the interference and can compose the interference compensation signal for application to the victim device that is impacted by the unwanted interference In other words, the interference compensation circuitcan couple to the channelthat is causing the interferencecan generate an interference compensation signal, and can apply the interference compensation signal to the recipient of the duobinary signaling pdf to word converter to provide interference cancellation, compensation, or correction.
A battery, not shown on FIG. As an alternative to a battery, a fuel cell or some other portable or small energy source duobinary signaling pdf to word converter supply the system with electricity. As discussed in more detail below, the system and specifically the interference compensation circuit can be operated in a manner that manages battery drain.
The interference compensation circuit can generate the interference compensation signal via a model of the interference effect. The model can generate the interference compensation signal in the form of a signal that estimates, approximates, emulates, or resembles the interference signal.
The interference compensation signal can have a waveform or shape that matches the actual interference signal. A setting or adjustment that adjusts the model, such as a set of modeling parameters, can define characteristics of this waveform.
The interference compensation circuit receives the signal that is representative of the aggressor signal or alternatively of the interference itself from a sensorthat duobinary signaling pdf to word converter adjacent one or both of the data busses In an exemplary embodiment, the sensorcomprises a conductor, associated with one or both of the data bus channels, that is dedicated to obtaining a sample of the aggressor signal.
Best stock option trading courses online example, the data bus can have a plurality of conductors that transmit data between the camera and the DSP chip and at least one other conductor that senses, sniffs, or samples the aggressor signal, or an associated EM or EMI field, rather carrying data for direct receipt.
For example, one of the data bus conductors can function as a sensor during a time interval when that specific conductor is not conveying purposeful data. In an exemplary embodiment, the sensoris integrated into a common structure to which the conductors of the data busadhere or are attached: