Abstract:
A mobile telecommunications apparatus includes a portable media device adapted to receive electronic data through a network, the portable media device comprising a first antenna adapted to receive electromagnetic signals of a particular frequency, the frequency is at least one of a radio frequency and a television (TV) frequency, and a headset in electrical communication with the portable media device and adapted to receive the electronic data through the network, the headset includes a switch coupled to the first antenna, a second antenna coupled to the switch, and a headset speaker comprising at least one of a mono headset speaker and a stereo headset speaker, the switch is adapted to combine operation of the first antenna and the second antenna into a dual operation diversity receiver. The network may comprise a Digital Video Broadcasting over Handheld (DVB-H) network.

Description:
BACKGROUND 
     1. Technical Field 
     The embodiments herein generally relate to Digital Video Broadcasting over Handheld (DVB-H) systems, and, more particularly, to implementation of diversity antennas in small portable media devices such as cell phones. 
     2. Description of the Related Art 
     DVB-H is a technical specification for bringing broadcast services to handheld receivers, terrestrial television (TV), portable TVs, mobile phones and other such mobile terminals. In DVB-H device systems, diversity receivers are used to improve the carrier-to-noise (C/N) performance and to provide diversity gain (e.g., by about 3 to 9 dB) in static to slow varying channel conditions and/or Doppler frequency (e.g., by twice) in mobile channel condition. In addition, they suppress part of the ingress noise and short echoes problems, thus offering significant reception performance improvement with portable and mobile reception in places where a single receiver would not function. 
     SUMMARY 
     In view of the foregoing, an embodiment provides a mobile telecommunications apparatus which includes a portable media device adapted to receive electronic data through a network, the portable media device comprising a first antenna adapted to receive electromagnetic signals of a particular frequency, the frequency is at least one of a radio frequency and a television (TV) frequency, and a headset in electrical communication with the portable media device and adapted to receive the electronic data through the network, the headset includes a switch coupled to the first antenna, a second antenna coupled to the switch, and a headset speaker comprising at least one of a mono headset speaker and a stereo headset speaker, the switch is adapted to combine operation of the first antenna and the second antenna into a dual operation diversity receiver. 
     The network may comprise a Digital Video Broadcasting over Handheld (DVB-H) network. The mono headset speaker of the headset may include one headset speaker. The mono headset speaker of the headset may include a first antenna element corresponding to a microphone (+), a second antenna element corresponding to a microphone (−), a third antenna element corresponding to a speaker (+) and a fourth antenna element corresponding to a speaker (−). The stereo headset speaker of the headset may include a plurality of speakers. 
     The stereo headset speaker of the headset may include a first antenna element corresponding to a microphone (+), a second antenna element corresponding to a microphone (−), a third antenna element corresponding to a left speaker (+), a fourth antenna element corresponding to a left speaker (−), a fifth antenna element corresponding to a right speaker (+), and a sixth antenna element corresponding to a right speaker (−). 
     The first antenna element and the second antenna element of the mono headset speaker and the stereo headset speaker of the headset may be coupled to an ideal capacitor to reduce a high impedance by creating an effective short circuit based on at least one of the radio frequency or the TV frequency without affecting an operation of the headset speaker. The first antenna of the portable media device may be perpendicular to the second antenna of the headset. The first antenna of the portable media device may be configured into a geometric shape of the portable media device. 
     In another embodiment, an antenna diversity system includes a first antenna adapted to transmit and receive electronic data through a network, the first antenna is positioned in a portable media device, and a second antenna adapted to receive audio signals through the network, the second antenna is positioned in a headset operatively connected to the portable media device, the headset comprises a headset speaker comprising a plurality of antenna elements, the plurality of antenna elements are combined by an ideal capacitor, and a switch coupled to the first antenna and to the second antenna, the switch is adapted to combine operation of the first antenna and the second antenna into a dual operation diversity receiver. 
     The headset speaker may be at least one of a mono headset speaker and a stereo headset speaker. The mono headset speaker of the headset may comprise one headset speaker. The stereo headset speaker of the headset may comprise a plurality of speakers. The first antenna may be adapted to receive electromagnetic signals of a particular frequency, the frequency may comprise at least one of a radio frequency and a television (TV) frequency, and the ideal capacitor may be adapted to reduce a high impedance by creating an effective short circuit based on at least one of the radio frequency and the TV frequency without affecting an operation of the headset speaker. 
     The first antenna of the portable media device may be positioned perpendicular to the second antenna of the headset. The first antenna of the portable media device may be configured into a geometric shape of the portable media device. In yet another embodiment, a portable Digital Video Broadcasting over Handheld (DVB-H) receiver system includes a portable media device component, a first antenna positioned in the portable media device component and adapted to transmit and receive electronic data through a network, a headset operatively connected to the portable media device component, a second antenna coupled to the headset, and a switch adapted to combine operation of the first antenna and the second antenna into a dual operation diversity receiver. 
     The headset may further include a plurality of antenna elements, the plurality of antenna elements are coupled to an ideal capacitor to reduce a high impedance in the portable media device by creating an effective short circuit based on at least one of a radio frequency and a television (TV) frequency without affecting an operation of the headset speaker. The first antenna of the portable media device may be operationally perpendicular to the second antenna of the headset. The first antenna of the portable media device may be configured into a geometric shape of the portable media device. 
     These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The embodiments herein will be better understood from the following detailed description with reference to the drawings, in which: 
         FIG. 1  illustrates a DVB-H diversity receiver having two identical single receivers with corresponding antennas; 
         FIG. 2  illustrates a system view of antenna selection diversity in TDM mode; 
         FIG. 3  illustrates a system view of antenna selection diversity in CW mode; 
         FIG. 4  illustrates a system view of signal combination diversity in Maximum Ration Combining (MRC) mode; 
         FIGS. 5A and 5B  illustrate a cell-phone headset having an antenna element ‘A’, an antenna element ‘B’, an antenna element ‘C’, and an antenna element ‘D’; 
         FIG. 6  illustrates a stereo headset in a mobile TV having an antenna element ‘A’, an antenna element ‘B’, an antenna element ‘C’ an antenna element ‘D’, an antenna element ‘E’, and an antenna element ‘F’; 
         FIG. 7A  illustrates the headset speaker having two wires; 
         FIG. 7B  illustrates an equivalent circuit for the headset speaker; 
         FIG. 7C  illustrates a graphical representation of a headset speaker and an equivalent circuit frequency response; 
         FIG. 7D  illustrates a graphical representation of the headset speaker and the equivalent circuit showing a high impedance at frequencies used for mobile TV; 
         FIG. 8A  illustrates a headset speaker with an ideal capacitor; 
         FIG. 8B  illustrates an equivalent circuit for the headset speaker with an ideal capacitor; 
         FIG. 8C  illustrates a graphical representation of an ideal capacitor equivalent circuit and frequency response; 
         FIG. 8D  illustrates a graphical representation of a headset speaker with an ideal capacitor frequency response at FM and TV frequencies; 
         FIG. 9A  illustrates a λ/4 monopole antenna having a single radiating element; 
         FIG. 9B  is an exploded view of the headset speaker terminated with an ideal capacitor; 
         FIG. 10  illustrates a system view of an antenna receiver diversity system; and 
         FIG. 11  illustrates an exploded view of a mobile TV receiver according to an embodiment herein. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein. 
     The embodiments herein provide a technique of implementing diversity antennas implemented in electronic devices which may occupy lesser space, hence making the size of the devices more portable and compact. The embodiments provide for the implementation of two diversity antennas in small portable media devices and/or cell phones. Due to the small feature size of the devices, two diversity antenna implementation are provided. One antenna is implemented in the portable media player or the handset and the other antenna is implemented in the headset. The two antennas may be implemented perpendicular to one another, and may be configured into the geometric shape of the cell phone or portable media devices. Referring now to the drawings, and more particularly to  FIGS. 1 through 11 , where similar reference characters denote corresponding features consistently throughout the figures, there are shown preferred embodiments. 
     Antenna diversity is a transmission technique in which the information-carrying signal is transmitted along different propagation paths. This can be achieved by using multiple receiver antennas (e.g., diversity reception) and/or by using multiple transmitting antennas (e.g., transmit diversity). A diversity combining circuit combines or selects the signals from the receiver antennas to constitute an improved quality signal. Diversity is a method used to improve to receive sensitivity of wireless devices. Various methods of antenna selection diversity such as Time-Division Multiplexing (TDM), CW, and Maximum Ration Combining (MRC) may be used. 
       FIG. 1  illustrates a DVB-H diversity receiver  100  having two identical single receivers  102  and  104 , with corresponding antennas  106 ,  108 . The single receivers  102  and  104  each include tuners  110 ,  112 , and baseband digital receivers  114 , 116 , as shown in  FIG. 1 . A combining block may maximize the SNR after the combination. The power consumption of the diversity receiver  100  with two antennas  106 ,  108  will thus be approximately twice the power consumption of the corresponding single receiver. 
       FIG. 2  illustrates a system view of antenna selection diversity in the TDM mode, having a headset FM/TV Antenna  202 , a FM/TV antenna inside or on terminal  204 , a switch  206 , a radio frequency (RF) tuner  208 , a digital baseband receiver  210 , and a video decoder  212  according to an embodiment herein. The most basic form of diversity uses antenna selection diversity in TDM mode. The receiver may select the antenna with a strongest signal. In the antenna selection diversity, the receiver does not know in advance that the signal condition at the alternate antenna is in fact better (or could be worse). Because of this, switching the antenna (at random) is just likely to produce a worse signal than a better one. Therefore, these systems usually wait until the primary antenna&#39;s signal is almost completely useless before switching. 
       FIG. 3  illustrates a system view of antenna selection diversity in CW mode, having headset FM/TV antenna  302 , a FM/TV antenna inside or on terminal  304 , RF tuner  1   306 , RF tuner  2   308 , switch  310 , digital baseband receiver  1   312 , and video decoder  314  according to an embodiment herein. The switch  310  is positioned after the RF tuner  308 . This method of diversity is an improvement on the previous one. The RF tuner  308  may be used to measure the signal strength at each antenna and report this information to the digital baseband receiver  1   312 . This may allow the digital baseband receiver  1   312  to know in advance which antenna path has the stronger signal and improves performance by allowing the receiver to switch to a better antenna sooner. 
       FIG. 4  illustrates a system view of signal combination diversity in MRC mode, having a headset FM/TV antenna  402 , a FM/TV antenna inside or on terminal  404 , an RF tuner  1   406 , an RF tuner  2   408 , a digital baseband receiver  1   410 , a digital baseband receiver  2   412 , a base band signal combiner  414 , and a video decoder  416  according to an embodiment herein. The strongest form of diversity, MRC, improves receiver sensitivity from between 6 to 9 dB. The MRC improves receiver sensitivity even further by combining the two signals together (no switching needed). In this method, the signals from each channel are added together, the gain of each channel is made proportional to the root mean square (RMS) signal level and inversely proportional to the mean square noise level in that channel, and different proportionality constants are used for each channel. The implementation of diversity antennas in electronic devices may occupy larger space, hence making the size of the devices less portable. 
       FIG. 5A  and  FIG. 5B  illustrate the basic construction of a cell-phone headset having an antenna element ‘A’  502 , an antenna element ‘B’  504 , an antenna element ‘C’  506 , and an antenna element ‘D’  508 , according to an embodiment herein. The antenna elements  502 - 508  are used to carry speaker and microphone electronic signals. The four antenna elements  502 - 508  are used for diversity without compromising the headset&#39;s primary function. The antenna element ‘A’  502  corresponds to microphone (+), the antenna element ‘B’  504  corresponds to microphone (−), the antenna element ‘C’  506  corresponds to speaker (+) and the antenna element ‘D’  508  corresponds to speaker (−). 
     With reference to  FIG. 5B , the wires (the antenna elements  502 - 508 ) inside the cell-phone headset are twisted to improve their immunity to interference.  FIG. 6  illustrates the basic construction of a stereo headset in a mobile TV having an antenna element ‘A’  602 , an antenna element ‘B’  604 , an antenna element ‘C’  606  an antenna element ‘D’  608 , an antenna element ‘E’  610 , and an antenna element ‘F’  612 , according to an embodiment herein. The antenna elements  602 - 612  are used to carry speaker and microphone electronic signals. The antenna elements  602 - 612  are for diversity without compromising the stereo headset&#39;s primary function. 
     The antenna element ‘A’  602  corresponds to a microphone (+), the antenna element ‘B’  604  corresponds to a microphone (−), the antenna element ‘C’  606  corresponds to a left speaker (+), the antenna element ‘D’  608  corresponds to a left speaker (−), the antenna element ‘E’  610  corresponds to a right speaker (+), the antenna element ‘F’  612  corresponds to a right speaker (−). The wires (e.g., the antenna elements  602 - 612 ) inside the stereo headset are twisted to improve their immunity to interference.  FIG. 7A  illustrates the headset speaker having two wires  702 ,  704 , according to an embodiment herein. The wire  702  corresponds to the speaker (+) and the wire  704  corresponds to the speaker (−). 
       FIGS. 7A and 7B  illustrates an equivalent circuit for the headset speaker having a positive terminal  706 , a negative terminal  708 , a resistor Rc  710 , an inductor Lc  712 , a resistor Rm  714 , an inductor Lm  716 , and a capacitor Cm  718 , according to an embodiment herein. With reference to  FIGS. 7A through 7C  illustrates a graphical representation of a headset speaker and an equivalent circuit frequency response, according to an embodiment herein. The graph is a plot of frequency (Hz) along x-axis and impedance (′Ω) along the y-axis. The plot shows two peak values when the impedance (′Ω) is above 16 and above 18. 
     The band of operation lies in the frequency (Hz) range 100 Hz-5 KHz.  FIG. 7D  illustrates a graphical representation of the headset speaker and the equivalent circuit showing a high impedance at frequencies used for mobile TV (the antenna frequency), according to an embodiment herein. The graph of  FIG. 7D  is a plot of frequency (Hz) along x-axis and impedance (′Ω) along the y-axis. The plot shows a peak value of the impedance (′Ω) above 18 at frequency 20-100 Hz. The impedance (′Ω) decreases with further increase in frequency up to 400 Hz after which the impedance (′Ω) shows a steep increase with increase in frequency. 
     The impedance reaches a peak value at higher frequencies (e.g., essentially an open circuit). The band of operation lies in the frequency (Hz) range 100 Hz-5 KHz.  FIG. 8A  illustrates the headset speaker with ideal capacitor termination having two wires  802 ,  804  and an ideal capacitor  806 , according to an embodiment herein. The wire  802  corresponds to the speaker (+) and the wire  804  corresponds to the speaker (−).  FIGS. 8A and 8B  illustrates an equivalent circuit for the headset speaker with an ideal capacitor having a positive terminal  808 , a negative terminal  810 , a resistor Rc  812 , an inductor Lc  814 , a resistor Rm  816 , an inductor Lm  818 , a capacitor Cm  820 , and an ideal capacitor  822 , according to an embodiment herein. 
     In one embodiment, terminating the speaker with an ideal capacitor has the effect of short circuiting the speaker wires (e.g., at TV frequencies) essentially making the two wires appear like one.  FIG. 8C  illustrates a graphical representation of an ideal capacitor equivalent circuit and frequency response, according to an embodiment herein. The graph of  FIG. 8C  is a plot of frequency (Hz) along x-axis and impedance (′Ω) along the y-axis. The plot shows a decrease in the impedance (′Ω) values with increasing frequencies.  FIG. 8D  illustrates a graphical representation of the headset speaker with ideal capacitor frequency response at FM and TV frequencies, according to an embodiment herein. 
     The graph represents a plot of frequency (Hz) along x-axis and impedance (′Ω) along the y-axis. The plot shows a peak value of the impedance (′Ω) above 18 at frequency 20-100 Hz, the impedance (′Ω) decreases with further increase in frequency up to 400 Hz after which the impedance (′Ω) reaches a peak value (e.g., a steep increase) with increase in frequency. The impedance (′Ω) shows a strong peak at a frequency of 100 KHz, after which the impedance (′Ω) starts decreasing with increasing frequencies. The ideal capacitor creates an effective short circuit at FM and TV frequencies without affecting the speaker operation. 
     The ideal capacitor is connected in parallel with the speaker to effectively eliminate high impedance (at TV frequencies).  FIG. 9A  illustrates a λ/4 monopole antenna having single radiating elements, according to an embodiment herein.  FIG. 9B  is an exploded view of the headset speaker terminated with an ideal capacitor having the headset speaker with a capacitor termination  902 , a circuit block  904 , and the antenna elements  906 , according to an embodiment herein. The antenna elements  906  correspond to speaker (+), speaker (−), microphone (+), and microphone (−). The circuit block  904  includes capacitors to create very low impedance at FM and TV frequencies (e.g., open circuit/high impedance at audio frequency). In one embodiment, ideal capacitors can be used at all portions of the headset circuits to create one effective wire. The speaker terminated with an ideal capacitor short circuits the speaker wires (e.g., at TV frequencies) essentially making the two wires appear like one. 
       FIG. 10  illustrates a system view of a receiver  1000  with antenna selection diversity having headsets  1002  and  1004 , a conventional FM/TV antenna inside or on terminal  1006 , and a switch  1008 , according to an embodiment herein. The headsets  1002  and  1004  correspond to FM/TV antenna connected to the nodes of the switch  1008 . The switch  1008  may be configured as a switch and microphone in an embodiment. The FM/TV antenna inside or on terminal  1006  may be an additional internal antenna which is allowed by the addition of another switch node in the switch  1008 . 
       FIG. 11  illustrates an exploded view of a mobile TV receiver  1100  having a memory  1102  with a computer set of instructions, a bus  1104 , a speaker  1108 , and a processor  1106  capable of processing the set of instructions to perform any one or more of the methodologies herein, according to an embodiment herein. The processor  1106  may also enable frequency samples to be consumed in the form of audio for output via speaker and/or earphones  1108 . 
     The processor  1106  may also carry out the methods described herein and in accordance with the embodiments herein. The received frequency domain sample may also be stored in the memory  1102  for future processing or consumption. The memory  1102  may also store specific information about the frequency domain sample available in the future or stored from the past. When the sample is selected, the processor  1106  may pass information. The information may be passed among functions within mobile TV receiver  1100  using the bus  1104 . 
     The techniques provided by the embodiments herein may be implemented on an integrated circuit chip (not shown). The chip design is created in a graphical computer programming language, and stored in a computer storage medium (such as a disk, tape, physical hard drive, or virtual hard drive such as in a storage access network). If the designer does not fabricate chips or the photolithographic masks used to fabricate chips, the designer transmits the resulting design by physical means (e.g., by providing a copy of the storage medium storing the design) or electronically (e.g., through the Internet) to such entities, directly or indirectly. The stored design is then converted into the appropriate format (e.g., GDSII) for the fabrication of photolithographic masks, which typically include multiple copies of the chip design in question that are to be formed on a wafer. The photolithographic masks are utilized to define areas of the wafer (and/or the layers thereon) to be etched or otherwise processed. 
     The resulting integrated circuit chips can be distributed by the fabricator in raw wafer form (that is, as a single wafer that has multiple unpackaged chips), as a bare die, or in a packaged form. In the latter case the chip is mounted in a single chip package (such as a plastic carrier, with leads that are affixed to a motherboard or other higher level carrier) or in a multichip package (such as a ceramic carrier that has either or both surface interconnections or buried interconnections). In any case the chip is then integrated with other chips, discrete circuit elements, and/or other signal processing devices as part of either (a) an intermediate product, such as a motherboard, or (b) an end product. The end product can be any product that includes integrated circuit chips, ranging from toys and other low-end applications to advanced computer products having a display, a keyboard or other input device, and a central processor. 
     The invention addresses the implementation of the two diversity antennas in small portable media devices and/or cell phones. Due to the small feature size of the devices, two diversity antenna implementation options are proposed. One antenna is implemented in the portable media player or the handset and the other antenna is implemented in the headset. The two antennas are implemented perpendicular to one another, and can even be built into the geometric shape of the cell phone or portable media devices. The diversity antenna implemented in electronic devices occupies lesser space, hence making the size of the devices more portable and convenient. 
     The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the appended claims.