Abstract:
A computer system which is capable of transmitting information content through walls and other barriers to a remote station such as a home entertainment system. The system tests a plurality of radio frequency channels to locate a channel that is not in use. Channels that are in already in use are rejected to avoid interference with existing services. Once an unused channel is located, the computer system displays indicia of that channel to the user and transmits information content on the unused channel. The remote station receives the information content. In one embodiment, the remote station is a home entertainment system with audio amplifiers and speakers substantially larger and more powerful than those typically associated with computer systems such as personal and other computers. In this manner the audio and/or video qualities of the computer system are substantially enhanced by transmitting content to the remote system for presentation in an acoustically and/or visually enhanced environment.

Description:
BACKGROUND  
         [0001]    The disclosure herein relates generally to computer systems and more particularly to a computer system capable of communicating information signals to a remote location.  
           [0002]    Many modern households include one or more personal computers. These personal computers are generally microprocessor-based, programmable electronic devices that store, process and retrieve data. The audio and graphics qualities of such computers have advanced substantially over time. However, these qualities can often be still further enhanced if the computer is connected to a home entertainment system. This is so because many home entertainment systems employ advanced speaker systems and displays that are generally substantially larger than those typically used with a personal computer. Many home entertainment systems include an audio video (A/V) receiver that provides AM, FM and video signal processing and audio amplification. These systems also often include a powerful multi-channel audio amplifier, multiple high quality audio speakers, a large display, a CD player, a digital versatile disk (DVD) player, and a videocassette recorder (VCR). Connecting a personal computer to such a home entertainment system can substantially enhance the computer user&#39;s experience.  
           [0003]    Home entertainment systems and computers are often not located in close proximity to one another. The computer may be in one room and the home entertainment system may be in another room some distance away. This immediately presents a significant challenge to the user who desires to connect the computer to the home entertainment system to take advantage of the system&#39;s superior acoustic and video qualities. Running wires through existing walls and ceilings to connect a computer to a remote entertainment system can be difficult, time-consuming and expensive.  
         SUMMARY  
         [0004]    The recitation herein of a list of desirable objects which are met by various embodiments of the present disclosure is not meant to imply or suggest that any or all of these objects are present as essential features, either individually or collectively, in the most general embodiment or in any of its more specific embodiments.  
           [0005]    That being said, one object is to provide a computer system that is capable of wireless communication with a remote entertainment system.  
           [0006]    Another object is to provide a computer system that communicates on a selected radio frequency with a remote entertainment system in a manner that does not cause interference to other services.  
           [0007]    Still another object is to provide a computer system that avoids radio frequency (RF) channels already in use when selecting a channel for wireless RF communication with a remote entertainment system.  
           [0008]    In accordance with one embodiment, a computer system is provided for communicating information content to a remote station. The computer system includes an RF processing section coupled to a digital processing section. The RF processing section includes a programmable channel receiver for receiving a plurality of radio frequency channels. The RF processing section further includes a programmable channel transmitter for transmitting information content on a selected channel. The digital processing section includes an information processor and a memory coupled to the information processor. The digital processing section further includes an information content source, coupled to the information processor, for supplying information content. The information processor instructs the programmable channel receiver to cycle through the plurality of radio frequency channels until an unused channel is found. Once an unused channel is found, the information processor instructs the programmable channel transmitter to transmit the information content on the unused channel which becomes the selected channel.  
           [0009]    In accordance with another embodiment, a computer system is provided for communicating information content to a remote station. The computer system includes a digital processing section having an information processor and a memory coupled to the information processor. The digital processing section also includes an information content source, coupled to the information processor, for supplying information content. The computer system further includes an RF processing section coupled to the digital processing section. The RF processing section includes a channel programmable receiver for receiving a plurality of radio frequency channels and testing the plurality of radio frequency channels to find an unused channel. The RF processing section further includes a channel programmable transmitter, coupled to the information content source, for transmitting the information content on the unused channel. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    The features of the described embodiments believed to be novel are specifically set forth in the appended claims. However, embodiments relating to both structure and method of operation may best be understood by referring to the following description and accompanying drawings.  
         [0011]    [0011]FIG. 1, labeled PRIOR ART, is a block diagram illustrating a conventional computer system employing a wire connection through a wall to a remote home entertainment system.  
         [0012]    [0012]FIG. 2A is a schematic block diagram of one embodiment of the disclosed computer system.  
         [0013]    [0013]FIG. 2B is a schematic block diagram of a remote entertainment system capable of receiving information signals from the computer system of FIG. 2A.  
         [0014]    [0014]FIG. 3 is a flow chart illustrating the process flow implemented by the computer system of FIG. 2A.  
         [0015]    [0015]FIG. 4 is a schematic block diagram of another embodiment of the disclosed computer system. 
     
    
     DETAILED DESCRIPTION  
       [0016]    Referring to FIG. 1, a block diagram shows a conventional computer  100  connected by wire  105  through one or more walls  110  to a remote home entertainment system  115 . Computer  100  includes a processor  120  coupled to a bus  125 . For examples, a Pentium series microprocessor manufactured by Intel Corporation, a Power PC series microprocessor by Motorola or other processor can be used as processor  120 . Bus  125  servers as a connection between processor  120  and other components of computer  100 . Microsoft Windows, Apple Macintosh OS, Linux or other operating systems can be employed as the operating system for computer  100 . An input device  130  is coupled to processor  120  to provide input to processor  120 . Examples of input devices include keyboards, touchscreens, microphones, and pointing devices such as a mouse, trackball or trackpad, for example. The operating system, programs and data are stored in a mass storage device  135 , which is coupled to processor  120  via bus  125 . Mass storage device  135  includes such devices as hard disks, optical disks, magneto-optical disks, floppy drives, CD-ROM drives, DVD drives and the like. An illustrative CD ROM/DVD drive  137  is shown coupled to bus  125  in FIG. 1. Computer  100  further includes a display  140  that is coupled to processor  120  by a video graphics controller  145 . A system memory  150  is coupled to processor  120  to provide the processor with fast storage to facilitate execution of computer programs. It should be understood that other busses and intermediate circuits can be employed between the components described above and processor  120  to facilitate interconnection between the components and the processor. Bridge chips (not shown) are often used to couple the processor to one or more conventional buses such as the PCI (Peripheral Component Interconnect) bus, the USB bus (Universal Serial Bus), the PCMCIA/PC Card bus, the ISA (Industry Standard Architecture) bus, and the IEEE 1394 bus, for example. These busses facilitate connection of the computer to interface cards and peripherals. Microprocessor  120  is capable of executing application programs stored in mass storage  135 .  
         [0017]    A sound card  155  is coupled to bus  125  to enable connection of computer  100  to external audio devices, such as local or remote audio speakers. Sound card  155  is connected via conductive wires  105  to a home entertainment system  115  in a location remote from computer system  100 . Considerable effort is required to drill holes in one or more walls  110  to permit sound card  155  to be connected to remote home entertainment system  1   15 . However, this effort is rewarded by the increased audio quality experienced by the listener. The listener experiences enhanced sonic quality because the amplifiers and speakers associated with most home entertainment systems are typically larger and more powerful than those generally employed by conventional computer systems. Unfortunately, drilling holes through walls or other barriers to establish a hard wire connection between the computer and the entertainment system is frequently not a reasonable option.  
         [0018]    [0018]FIG. 2A shows a computer system  200  for wirelessly transmitting audio or audio/video information signals to a remote station such as a remote home entertainment system, for example. In this particular embodiment, the system performs this transmission by modulating the audio information or content on a radio frequency carrier signal. Frequency modulation, amplitude modulation and phase modulation are examples of modulation techniques that may be employed. System  200  is capable of transmitting on a plurality of different radio frequency channels. Prior to transmission, the system checks a candidate radio frequency channel to assure that the channel is clear. In other words, computer system  200  checks to see if the candidate channel is unused or not busy. If the radio frequency channel is clear, then transmission commences. However, if system  200  finds that the candidate radio frequency channel is not clear, then the system moves to a different candidate frequency channel and repeats the test. New candidate channels are so tested until a clear radio frequency channel is located. In this manner, interference to services already occupying candidate radio frequency channels is avoided or substantially reduced.  
         [0019]    Computer system  200  and its operation are now described in more detail. System  200  of FIG. 2A contains some elements in common with computer  100  of FIG. 1 with like numbers indicating like elements. System  200  includes a digital processing section  200 A and a radio frequency (RF) processing section  200 B as illustrated. It is noted that the RF processing section can be integrated within the computer system. For example, the RF processing section can be situated within the same chassis or enclosure as the digital processing section. Alternatively, the RF processing section can be a separate module or standalone device that is coupled to the digital processing section.  
         [0020]    An embodiment wherein RF processing section  200 B is integrated with respect to digital processing section  200 A is now discussed with reference to FIG. 2A. A sound card  155  is coupled to bus  125  of system  200  to provide audio to a local speaker system  160 . Sound card  155  may have one (monaural), two (stereo), or more channel audio outputs indicated collectively as  155 A. An example of one sound card that can be employed as sound card  155  is the SoundBlaster 64 v PCI card manufactured by Creative Technology Ltd. Audio content for sound card  155  can be retrieved from mass storage  135 , CD ROM/DVD  137 , from the Internet interface  172  or may be generated by computer system  200  itself. Devices that can be employed as Internet interface  172  include cable modems, DSL modems, ISDN modems, as well as dial-up and wireless modems, for example. The internet interface  172  advantageously provides system  200  with audio and video content beyond that generated by system  200  or stored in system  200  at mass storage  135  or CD/DVD drive  137 .  
         [0021]    Digital processing section  200 A includes an I/O interface  175  coupled between bus  125  and RF processing section  200 B to provide audio or audio/video content to RF processing section  200 B. RF processing section  200 B is given the task of transmitting this content to a remote entertainment system. A data stream including audio or audio/video is communicated to RF Processing section  200 B via I/O interface  175 . The data stream can include analog information, digital information or a combination of analog and digital information. Control commands from digital processing section  200  are also conveyed across interface  175  to enable digital processing section  200 A to control the operation of RF processing section  200 B in this embodiment. Responsive status information such as candidate frequency availability is communicated from RF processing section  200 B back to digital processing section  200 A via I/O interface  175 . One type of interface that can be employed as interface  175  is a Universal Serial Bus (USB) interface. Other interfaces such as serial, parallel and IEEE 1394 could be employed as well.  
         [0022]    RF processing section  200 B includes a transmitter  170 , a receiver  180  and a control circuit  185  through which digital processing section  200 A controls the operation of transmitter  170  and receiver  180 . A digital audio data stream (content) is fed through I/O interface  175  to control circuit  185  which supplies a corresponding analog audio signal to transmitter  170  for transmission. This analog signal is designated AUDIO although it may contain video content as well. An embodiment is also contemplated wherein this content signal provided to transmitter  170  is digital audio or digital audio/video. Control circuit  185  includes a RESET TX port that is coupled to transmitter input  170 B to reset the transmitter on command from digital processing section  200 A. The operating frequency of transmitter  170  is programmable. Control circuit  185  includes a PROGRAM TX port that is coupled to transmitter input  170 D to set the operating frequency of transmitter  170 . A PROGRAM TX signal is generated by control circuit  185  under program control of digital processing section  200 A to set the operating frequency of transmitter  170 . In this manner, a control program executed in digital processing section  200 A sets the frequency of transmitter  170 .  
         [0023]    Control circuit  185  further includes a RESET RX port that is coupled to receiver input  180 B to enable the control program to reset receiver  180 . Control circuit  185  also includes a PROGRAM RX port that is coupled to receiver input  180 C to enable the control program to set the operating frequency of receiver  180 . The operating frequency of receiver  180  is programmable and is referred to as the candidate operating frequency while such frequencies are being tested for usability. Computer system  200  tests candidate frequencies until an unused frequency is found which is available for use by system  200  to transmit content to a remote entertainment system. Receiver input  180 A is coupled to an antenna  185  and transmitter output  170 A is coupled to an antenna  177 . In this particular embodiment, receiver  180  is programmable to receive all channels within the standard broadcast FM band, namely 88 MHz to 108 MHz. Transmitter  170  is programmable to transmit on any channel within the 88 MHz to 108 MHz FM band. Of course, other bands and channels can be used as desired according to the particular application.  
         [0024]    In this embodiment a control program is stored in mass storage  135  to govern the selection of a radio frequency channel for system  200 . Receiver  180  and transmitter  170  are thus said to be under program control as will be discussed in more detail subsequently. When system  200  is powered up, processor  120  is initialized to commence system operation. After the operating system loads, the radio frequency control program stored in mass storage  135  is loaded and begins to control the operation of receiver  180  and transmitter  170 . Receiver  180  and transmitter  170  are both reset. More particularly, receiver  180  is reset when control circuit  185  provides a RESET RX signal to the reset input  180 B of receiver  180 . Transmitter  170  is reset when control circuit  185  provides a RESET TX signal to the reset input  170 B of transmitter  170 . The control program executed by digital processing section  200 A then instructs control circuit  185  to generate a PROGRAM RX signal which programs receiver  180  to listen to a first candidate frequency, for example 88.1 MHz. The PROGRAM RX signal is provided to input  180 C of receiver  180 . The first candidate frequency is then tested to see if it already in use; i.e. a test is conducted to determine if a signal is already present at the candidate frequency.  
         [0025]    To facilitate this signal presence test, a Motorola MC13156 FM demodulator is employed in receiver  180  in this particular embodiment. This demodulator includes a DETECT pin  180 D which changes state when a signal is detected at the programmed frequency of operation. When receiver  180  receives a signal at the frequency set by the PROGRAM RX signal, the DETECT signal at output  180 D goes high. However, if the frequency were unused, i.e. the frequency is not occupied by a significant signal, then the DETECT signal remains low. The DETECT signal is fed back to digital processing section  200 A via control circuit  185  and USB interface  175  to provide information to processor  120  indicating whether or not the selected radio frequency is in use or busy. In this example, receiver  180  detects a significant signal at the first candidate radio frequency and thus the frequency is found to be already in use. Under these conditions transmission is not desired. Digital processing section  200 A instructs control circuit  185  to keep the STANDBY signal at transmitter input  170 C in the inactive state to maintain transmitter  170  in standby mode. The AUDIO signal provided to transmitter input  170 E is thus not transmitted. Digital processing section  200 A now operates under program control to cause control circuit  185  to change the PROGRAM RX signal provided to receiver input  180 C signal to correspond to a second candidate frequency, 88.3 MHz. In short, we increment to a second candidate frequency and test again to determine if the frequency is in use.  
         [0026]    In this example, it is assumed that the second candidate frequency is not in use. Thus, receiver  180  receives no significant signal when it tests the second candidate frequency and the DETECT signal goes low. In response, digital processing section  200 A operates under program control to cause control circuit  185  to shift the transmit frequency to the second candidate frequency, 88.3 MHz, which was found not to be in use. More particularly, control circuit  185  sends transmitter input  170 D a PROGRAM TX signal corresponding to the second candidate frequency. Under program control the control circuit  185  now changes the STANDBY signal provided to transmitter input  170 C to an active state causing transmission to commence. The audio content provided to transmitter input  170 E is thus transmitted at the second candidate frequency, 88.3 MHz since it was found to be clear.  
         [0027]    If the second candidate radio frequency or channel had been busy, digital processing section  200 A would continue the search for an unused RF channel until an unused channel was found. Since the second candidate frequency has been selected for transmission, the second candidate frequency is now displayed on display  140  to inform the user as to which frequency the remote station  300  of FIG. 2B should be tuned to receive the content transmission.  
         [0028]    As illustrated in FIG. 2B, one version of remote station  300  includes a receiving antenna  305  that is coupled to an input of audio/video (A/V) receiver  310 . Front left speaker  315 A, front right speaker  31   5 B, rear left speaker  315 C and right rear speaker  315 D are coupled to respective audio outputs of AN receiver  310 . While this particular version includes four audio outputs and speakers, a lesser or greater number of speakers can be employed according to the particular application. A/V receiver  310  includes an FM tuner. As mentioned earlier, when system  200  selects a clear radio frequency channel on which to transmit, the frequency or other identifying indicia of this channel (e.g. a channel number) is displayed on display  140 . In this manner, the user is informed as to which frequency the FM tuner in A/V receiver  310  should be tuned. The audio content which is modulated on the transmitted RF signal is demodulated by receiver  310 , amplified by an audio amplifier in receiver  310  and fed to speakers  31   5 A -  315 D. Content from computer system  200  is thus wirelessly transmitted through one or more walls  110  or other barriers to remote station  300 . Remote station  300  is also referenced herein as an entertainment system, specifically a remote entertainment system. Entertainment system  300  is remote from computer system  200  in that it is separated from computer system  200  by some distance that is traversed by the wireless transmissions described herein.  
         [0029]    It should be noted that in actual practice antennas  177  and  185  can be implemented as a single antenna by providing receiver  180  and transmitter  170  with appropriate transmit-receive (TR) switching circuitry.  
         [0030]    [0030]FIG. 3 is a flowchart describing the operation of the aforementioned control software or control program that is stored in mass storage  135  to provide program control for computer system  200 . The control software, when executed by processor  120 , controls the operation of system  200  of FIG. 2A as it seeks out a clear radio frequency channel on which to transmit content to remote station  300  of FIG. 2B. Process flow is now described with reference to FIG. 3. The system is initialized as per block  300  and a counter “i” is set to an initial value of  1 . Digital processing section  200 A instructs control circuit  185  to generate a STANDYBY signal with a low state to set transmitter  170  to the “stand-by” state as per block  305 . Then, as per block  310 , digital processing section  200 A then instructs control circuit  185  to generate a PROGRAM RX signal which causes programmable receiver  180  to be tuned to the first candidate frequency channel, FC(i) wherein i=1. In one example, the frequency of channel  1 , namely FC (1), is 88.1 MHz. A test is now conducted as per decision block  315  to determine if the first candidate frequency channel FC(1) is already in use. If receiver  180  finds a signal on the first candidate frequency FC(1), then the DETECT signal returned to digital processing section  200 A via control circuit  185  exhibits a value indicating that the frequency is in use. In contrast, if receiver  180  finds no substantial signal at the first candidate frequency FC(1), then a DETECT signal indicating a free channel is returned to digital processing section  200 A.  
         [0031]    For example purposes however, assume that a signal is received at the first candidate frequency FC(1). Digital processing section  200 A tests the DETECT signal and determines that the first candidate frequency FC(1) is indeed busy as per decision block  315 . The counter “i” is now incremented by 1 as per block  320 . Digital processing section  200 A changes the candidate frequency FC (i) to the next candidate frequency, for example, 88.3 MHz as per block  325 . To perform this operation, digital processing section  200 A instructs control circuit  185  to change the PROGRAM RX signal to a value corresponding to the next candidate frequency, FC(i). In response, receiver  180  is then tuned to a channel corresponding to this new candidate frequency.  
         [0032]    A test is now conducted at decision block  315  to determine if the new candidate frequency is in use. In this example, it is determined that the new candidate frequency is not in use, but rather is available for transmission. Process flow now continues to block  330  at which this new candidate frequency, FC(i) (for example, 88.3 MHz) is displayed to the user on display  140 . In this manner, the user knows to which frequency the remote station  300  should be tuned to receive content from system  200 . As per block  335 , digital processing section  200 A instructs control circuit  185  to generate a PROGRAM TX signal to tune transmitter  170  to the candidate frequency, FC(i), which was found to be clear for use. Digital processing section  200 A then instructs control circuit  185  to generate a STANDBY signal with an active state to turn on transmitter  170  at block  340  and commence transmission of content at block  345 . If the user desires to reset the system, the user initiates a reset by an appropriate mouse click selection on display  140  as indicated at block  350 . Process flow then goes back to block  300  and the system is re-initialized.  
         [0033]    [0033]FIG. 4 shows another embodiment of the computer system as system  400 . Like system  200  discussed earlier, system  400  includes both a digital processing portion and an RF processing portion. However, in this particular embodiment, RF processing unit  400 B is a unit that is physically separate from digital processing section  400 A. RF processing unit  400 B and digital processing section  400 A are not integrated in the same chassis, although such integration is contemplated in yet another embodiment.  
         [0034]    It will be noted that digital processing section  400 A and RF processing unit  400 B have similarities to sections  200 A and  200 B, respectively of FIG. 2A, with like numbers indicating like elements. However, in system  400  an analog audio line  187  connects sound card output  1   55 A to AUDIO transmitter input  1   70 E. In this manner, content is provided to transmitter  170  for transmission to a remote station or entertainment system. It will be recalled that in system  200  of FIG. 2A, digital processing section  200 A controlled frequency selection and channel testing. In contrast, in the system  400  embodiment of FIG. 4, RF processing unit  400 B controls the frequency selection and testing.  
         [0035]    RF processing unit  400 B includes a control circuit  405  having a state machine therein which controls the operation of RF processing unit  400 B. Control circuit  405  and the state machine therein implement substantially the same control operations and functions as described earlier in flow chart of FIG.3. The difference is that RF processing unit  400 B carries out these control operations and functions of the FIG. 3 flowchart in a substantially standalone manner independent of digital processing section  400 A. More particularly, control circuit  405  and its state machine generate the PROGRAM TX, STANDBY, RESET TX, PROGRAM RX, AND RESET TX signals that control candidate frequency selection and testing. Control circuit  405  and its state machine implement substantially the same steps called out in the flowchart FIG. 3. In this manner each candidate frequency is programmed into receiver  170  and tested to determine if it is in use before transmission of content is permitted  
         [0036]    In more detail, operation commences after system initialization with control circuit  405  generating a STANDBY signal which puts transmitter  170  in a standby state until a clear frequency channel is found. Control circuit  405  then generates an appropriate PROGRAM RX signal to set receiver  180  to a first candidate frequency. For discussion purposes it is assumed that the first candidate frequency is already in use by another service. Consequently, a signal is detected on the first candidate frequency and the DETECT signal goes high. The state machine recognizes the high DETECT signal and causes the control circuit to change the PROGRAM RX signal to value which instructs receiver  180  to move to a second candidate frequency. To further our discussion it is assumed that the second candidate frequency is not in use. Since no signal is detected by the receiver, the DETECT signal goes low. The state machine responds to the DETECT signal going low and control circuit  405  generates a PROGRAM TX signal which instructs transmitter  170  to tune to the second candidate frequency in preparation for transmitting the content. Control circuit  405  then changes the state of the STANDBY signal to the active state to turn on transmitter  170  to commence transmission of the content. A display  410  is coupled to receiver  180  to display the frequency of the transmitted signal. In this manner, the user is informed of the frequency channel that is determined to be clear. The user then tunes the receiver of the remote entertainment system to the clear channel to receive the transmitted content.  
         [0037]    From the above discussion it should be understood that the function of moving from candidate frequency channel to candidate frequency channel and testing each channel to determine if it is already in use can be controlled by software, namely the control program already discussed with respect to system  200  of FIG.2. Alternatively, this functionality can be implemented by equivalent hardware such as that of RF processing unit  400 B in system  400  of FIG. 4.  
         [0038]    The foregoing has described a computer system that is capable of wireless communication with a remote entertainment system. Advantageously, the computer system communicates on a selected radio frequency channel with a remote entertainment system in a manner that does not cause interference to other services. The problem of connecting a computer to a remote entertainment system when there are one or more barriers between the computer and the entertainment system is solved by the disclosed computer system. The computer system also solves the problem of connecting a computer system to a remote entertainment system in the same room when it is not convenient or desirable to connect the computer system to the entertainment system with conventional wires.  
         [0039]    While various embodiments have been described, it will be understood that these embodiments are illustrative and that many variations, modifications, additions and improvements of the embodiments described are possible. For example, it should be understood that the disclosed computer system is not limited to operating on the particular frequency band discussed in the examples above. Rather, other bands of higher or lower frequency can be employed as well. Moreover, the computer system is not limited to FM, but can be employed with other modulation methods such as AM, phase modulation, single sideband and double sideband, for example. While the particular embodiments discussed provide for transmission of audio content, it will be appreciated that the disclosed techniques can also be used to transmit video on an unused candidate channel or to transmit a combination of audio and video on an unused channel. Additional bandwidth may be required for channels in such applications. Those skilled in the art will readily implement the steps necessary to provide the structures and methods disclosed herein, and will understand that the process parameters, materials, and dimensions are given by way of example only and can be varied to achieve the desired structure as well as modifications which are within the scope of the embodiments disclosed herein. Variations and modifications of the embodiments may be made based on the description set forth herein, without departing from the scope and spirit of the embodiments as set forth in the following claims.