Abstract:
Signal processing electromagnetic signals with specific materials. A processing portion may be composed of a specific material having a particular shape, a certain dielectric constant and a crystal structure that permits efficient propagation of the signals being processed. Such processing is very fast and utilizes little or no power due to its passive nature.

Description:
BACKGROUND  
       [0001]     The invention pertains to processing, and particularly to processing for wireless communications. More particularly, the invention pertains to low power and high speed processing.  
       SUMMARY  
       [0002]     The invention is a signal processor that uses specific materials in for processing electromagnetic signals. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0003]      FIG. 1  is a schematic diagram of a device using a material for an electronic processing function;  
         [0004]      FIG. 2  is a block diagram of the transmitter of the system; and  
         [0005]      FIG. 3  is a block diagram of the demodulating portion of the receiver.  
         [0006]      FIG. 4  illustrates a wavelength separating property of a prism relative to electromagnetic radiation; and  
         [0007]      FIG. 5  is a table of materials, their transmission frequencies and respective dielectric constants.  
     
    
     DESCRIPTION  
       [0008]     The present invention relates to processing for wireless networks where special materials may be used as a processing mechanism. There is a need for high speed signal processing at low power consumption in wireless networks. High speed processing may eliminate time delays that can destabilize a system if a communication link is part of a feedback loop. The low power consumption aspect of the system may extend battery life of remote portions of the system thereby reducing human effort to replace or charge the batteries.  
         [0009]     In a manner that colored glass filters light in a fashion of a passive band pass filter, or a prism that separates out light according to wavelength, which in effect performs a Fourier transform, one may use various kinds of materials in certain shapes tuned to specific electromagnetic frequency ranges to perform filtering and Fourier transform operations. Since such operations occur at the speed of wave propagation, the speed of operation is maximal. Additionally, these devices are passive, so no power is needed to-operate the devices. A limitation may be the size of the devices which increase with the wavelength of electromagnetic signals to be processed. These devices may have a convenient size with electromagnetic radiation in the millimeter (mm) range.  
         [0010]     The materials used for various processing stages may be selected according to shape, dielectric constant and/or refractive index. Further, one may vary the charge distribution in the materials for varying or tuning the materials for different frequencies (as may be done in the optics field, for instance, fiber optics).  
         [0011]     In the processor aspect of the design, one may first determine the wavelengths to be dealt with. Then, the crystal structure needed to pass or disperse radiation in the selected wavelength ranges may be determined. An illustrative example of the present processor may be a front end of a wireless receiver.  
         [0012]     A communication system  10  in  FIG. 1  may have a transmitter unit  11  that emits a radio frequency signal  12  to a receiver unit  13 . Two or more messages or other kinds of information may be sent by transmitter unit  11  via a single emission or signal  12  to the receiver unit  13 . For an illustrative example, the transmitter unit  11  may have a number of RF generators in a transmitter  14 . Connected to each generator may be an amplitude modulator. Each amplitude modulator may have a signal input that represents a message. Input to transmitter unit  14  may be four signals, A 1 , A 2 , A 3  and A 4 , from units  1 ,  2 ,  3  and  4 , respectively. There may be more or less signals. Each signal may modulate an RF transmitter output via an amplitude modulator. Other kinds of modulation may be utilized.  
         [0013]     Signal A 1  may modulate a first radio frequency RF 1  from an RF generator  15  via a modulator  16 . Signal A 2  may modulate a second radio frequency RF 2  from an RF generator  17  via a modulator  18 . Signal A 3  may modulate a third radio frequency signal RF 3  from an RF generator  19  via a modulator  20 ; and signal A 4  may modulate a fourth radio frequency signal RF 4  from an RF generator  21  via a modulator  22 . There may be more signals, RF generators and modulators for providing modulated RF signals at additional frequencies.  
         [0014]     The modulated RF signals A 1 ω 1 (t)sin ω 1 t, A 2 ω 2 (t)sinω 2 t, A 3 ω 3 sinω 3 t and A 4 ω 4 sinω 4 t from modulators  16 ,  18 ,  20  and  22 , respectively, may go to a combiner or multiplexer  23 . The modulated RF signals are combined and conveyed as a resultant modulated RF signal  24  on one line which may be connected to an input of an RF power amplifier  25 . The resultant signal  24  may amplified many times in terms of electrical power (I 2 V) into a power signal  26  which may go to an antenna  27 . There may be four or more or less modulated RF signals combined. Antenna  27  may emit the power signal  26  as a radiation signal  12 . Signal  12  may be emanated in all directions from antenna  27 . However, the interested direction of signal  12  is the one looking towards a receiver unit  13 . The bandwidth of the combined signal  24  may range from the lowest frequency to the highest frequency of the RF generators. Thus, signal  12  may be regarded as a broadband signal.  
         [0015]     The modulated RF signal  12  may impinge and propagate through a prism shaped piece of a certain material having a selected dielectric constant depending on the bandwidth of the signal  12 . Due to the propagation speed of electromagnetic radiation  12  varying according to frequency, there may be a “refraction” of signal  12  through a “prism”  28 . Signal  12  may emanate from device  28  in a spread out fashion (i.e., in a spatial fashion according to frequency) in the same manner as a prism that receives a broadband light which may emanate from the prism in a spatially dispersed fashion according to wavelength or color, i.e., like a rainbow. Signal  12  may effectively be demultiplexed into signals  31 ,  32 ,  33  and  34 , ranging from the shorter wavelength to the longer wavelength, respectively.  
         [0016]     An array of antenna detectors  35 ,  36 ,  37  and  38  may be in the vicinity of prism  28  so as to detect signals  31 ,  32 ,  33  and  34 . The array may be one of various configurations. The example shown in  FIG. 1  is for illustrative purposes. The signals  31 ,  32 ,  33  and  34  may be input to demodulators  46 ,  47 ,  48  and  49  of device  39  via detectors  35 ,  36 ,  37  and  38 , respectively. The demodulation of the signals  31 ,  32 ,  33  and  34  may result in signals A 1 , A 2 , A 3  and A 4 , respectively, output to units  41 ,  42 ,  43  and  44 .  
         [0017]     In the design of optical systems for the millimeter and submillimeter wavelength ranges one may choose from a number of materials having suitable properties. The choice of materials depends on losses and dielectric constants. Refractive index and absorption data are factors in the selection of dielectrics for optical design. The same principle may apply to light or electromagnetic radiation that enters a prism of optical or dielectric material, respectively. The index of refraction (n) of a material may be defined experimentally to be the ratio of the sine of the incident angle (θ i ) for electromagnetic radiation  56  ( FIG. 4 ) such as light in a vacuum (or air) to the sine of the refracted angle (θ r ) in that material (e.g., prism  58 ), where n=sinθ i /sinθ r . The angle θ i  is of the acute angle of incident ray  56  relative to a normal  59  (perpendicular line) relative to the incident surface  61 . The angle θ r  is of the acute angle of a refracted ray  52  relative to the normal  59  (perpendicular line) relative to the incident surface  61 . The ray  52  may be refracted again as it goes from a material  58  to a less dense material  57  (air). The amount of refraction of the ray  56  and  52  is affected by the wavelength of the electromagnetic ray. Since rays  51 ,  52 ,  53  and  54  are refracted by different amounts in the same material transition, one may conclude that they have different wavelengths. The greater the refraction, shorter is the wavelength (λ). Thus, λ 51 &gt;λ 52 &gt;λ 53 &gt;λ 54 .  
         [0018]     In  FIG. 4 , a path of a ray  56  of electromagnetic radiation may pass from a less dense medium  57  (like air) into a more dense medium  58  (like glass or a dielectric material). The refraction (bending) of the ray  56  occurs as it transitions into the other material  58  because the electromagnetic radiation slows down in the material  58 , so the index of refraction n may be found to be the ratio of the speed of the radiation (c) in a vacuum to the speed of light in a material (v), i.e., n=c/v.  
         [0019]     The index of refraction may be given in terms of the electric permittivity ε and magnetic permeability μ by
 
 n= (εμ) 1/2 
 
 and in terms of the dielectric constant k e  and relative permeability k m  by
 
 n= ( k   e   k   m ) 1/2 
 
 Since μ and k m  are usually ≈1, the previous two equations can usually be approximated using the Maxwell relation for the index of refraction as
 
n˜ε 1/2  and
 
n˜k e   1/2 .
 
 Data may be presented in terms of the real part of the dielectric constant, {acute over (ε)}, and the loss tangent, tanδ, which may commonly be used in microwave electronics. The complex dielectric constant is
 
{circumflex over (ε)}=ε′− iε″ 
 
 where i=√{square root over (−1)}, and
 
tanδ=ε″/ε.
 
 In millimeter optics, perhaps it may be more common to deal with the refractive index, n, and power absorption coefficient, α. These are related to the complex refractive index
 
 {circumflex over (n)}=n−ik 
 
with
 
α=4πν k/c, 
 
 where c is the speed of light, and ν is the frequency. For non-magnetic materials the two representations are related by
 
ε′= n   2   −k   2  and ε″=2 nk 
 
or, for low loss materials,
 
ε′=n 2  and tanδ=2 k/n=αc/ 2π nν. 
 
 One may note that α is often given in units of cm −1  or Np cm −1 . In the conventions of millimeterwave optics, the neper (Np) may be used as a measurement of power absorption (1 Np=4.343 dB), in contrast to the normal electrical engineering definition in terms of amplitude. 
 
         [0020]      FIG. 5  is a table of various dielectric materials with frequency ranges, temperatures of testing and their resultant refractive indices.  
         [0021]     Although the invention has been described with respect to at least one illustrative embodiment, many variations and modifications will become apparent to those skilled in the art upon reading the present specification. It is therefore the intention that the appended claims be interpreted as broadly as possible in view of the prior art to include all such variations and modifications.