Patent ID: 12191919

DETAILED DESCRIPTION

In the drawings, like reference numerals designate identical or corresponding parts throughout the several views. Further, as used herein, the words “a,” “an” and the like generally carry a meaning of “one or more,” unless stated otherwise.

Furthermore, the terms “approximately,” “approximate,” “about,” and similar terms generally refer to ranges that include the identified value within a margin of 20%, 10%, or preferably 5%, and any values therebetween.

Aspects of this disclosure are directed to systems and methods for integrating ultra-wideband (UWB) and free space optical (FSO) communication for realizing a secure and high-throughput body area network (BAN) architecture based on optical code division multiple access (OCDMA).

Nodes in a BAN are miniature wearable or implantable battery-powered wireless sensors which continuously transmit real-time vital physiological data of a human body (for example, a patient) to a remote healthcare center while remaining in close proximity to the human body. Therefore, BAN nodes should have the features of high data rates and low transmit powers to protect the human body, environment, and biomedical equipment from harmful exposure to electromagnetic radiation and EMI. In an example, UWB signals have low allowable transmission power and high data rates.

The present disclosure presents a low transmit power, low cost, and secure optical body area network (OBAN) composed of a plurality of UWB BAN nodes.

FIG.1Adepicts a block diagram of a BAN architecture100, according to aspects of the present disclosure.

According to an embodiment, the BAN architecture100includes a plurality of ultra-wideband (UWB) BAN node devices102-(1-N), a control node device104, and a remote node device106. In an example, the remote node device106may be a remote healthcare center. The control node device104may further include a spectral amplitude coding-optical code division multiple access (SAC-OCDMA) encoder108, an optical coupler110, and a plurality of Mach-Zehnder modulators (MZMs)112-(1-M). A Mach-Zehnder modulator is a device that is used for controlling the amplitude of an optical wave.

Further, the SAC-OCDMA encoder108includes a continuous wave (CW) laser array114. The remote node device106may include an SAC-OCDMA decoder116. The SAC-OCDMA decoder116may include a wavelength division multiplexing (WDM) de-multiplexer118. The remote node device106may also include a plurality of optical couplers120-(1-O), a plurality of positive-intrinsic-negative (PIN) photo-detectors122-(1-P), a plurality of direct current (DC) block circuits124-(1-Q), a plurality of electrical amplifiers126-(1-R), a plurality of electrical splitters128-(1-S), and a plurality of electrical low pass filters130-(1-T). An optical coupler is a semiconductor device, which is designed to transfer electrical signals by using light waves in order to provide coupling with electrical isolation between circuits or systems. Examples of optical couplers include splitters, combiners, X-couplers, etc. A PIN photodetector is a photodiode with a wide intrinsic semiconductor region in between the p-type and n-type semiconductor regions. A DC blocking circuit is a circuit that prevent the flow of DC signals into systems while allowing higher frequency RF signals to pass through. An electrical amplifier is a device that can increase the power of a signal (a time-varying voltage or current). An electrical low pass filter is a filter that passes signals with a frequency lower than a selected cutoff frequency and attenuates signals with frequencies higher than the cutoff frequency.

FIG.1Bdepicts a detailed example of the BAN architecture100, according to aspects of the present disclosure.

According to an aspect, the plurality of ultra-wideband (UWB) BAN node devices102-(1-N) may be a close proximity to a patient and configured to measure real-time physiological data of the patient, such as pulse rate, body temperature, electrocardiogram (ECG), and electroencephalogram (EEG) activity. For example, the plurality of UWB BAN node devices102-(1-N) can be disposed or mounted on (or attached to) human body (or clothes) of the patient.

For ease of explanation and understanding, description provided is with reference to one patient, however, the description is equally applicable to multiple patients. In an example, the plurality of UWB BAN node devices102-(1-N) may include at least four UWB BAN node devices. As shown inFIG.1B, the four UWB BAN node devices include a first UWB BAN node device102-1, a second UWB BAN node device102-2, a third UWB BAN node device102-3, and a fourth UWB BAN node device102-4. Further, the plurality of UWB BAN node devices102-(1-N) may include a plurality of electrical bandpass filters (EBPFs). In an example, the first UWB BAN node device102-1may include a first EBPF132-1, the second UWB BAN node device102-2may include a second EBPF132-2, the third UWB BAN node device102-3may include a third EBPF132-3, and the fourth UWB BAN node device102-4may include a fourth EBPF132-4. In an example, the first EBPF132-1, the second EBPF132-2, the third EBPF132-3, and the fourth EBPF132-4are centered at fC1=4 GHz, fC2=4.5 GHz, fC3=5 GHz, and fC4=5.5 GHz, respectively. According to an aspect, the BAN architecture100may include any number of UWB BAN node devices and EBPFs.

In an aspect, the plurality of UWB BAN node devices102-(1-N) may transmit the physiological data to the control node device104using UWB signals. In an example, each of the UWB signals may operate at a different carrier frequency. In an example, each of the plurality of UWB BAN node devices102-(1-N) may transmit the physiological data over an additive white Gaussian noise (AWGN) wireless channel at a data rate of 30 Mbps in the form of Federal Communications Commission (FCC)-compliant UWB mono-cycle pulses which are generated by taking a first-order derivative of electrical Gaussian pulses. Further, each of the plurality of UWB BAN node devices102-(1-N) may transmit at a different radio frequency to avoid interference at the control node device104.

According to an aspect, to simulate the effect of the AWGN wireless channel on the transmitted UWB signals, a white noise source represented by n(t) following normal distribution is coupled with each UWB BAN node device, as shown inFIG.1B. The time-domain plots of UWB mono-cycle pulses generated by the UWB BAN nodes devices are shown inFIGS.2A-2D. In particular,FIG.2Adepicts time-domain plot202of UWB mono-cycle pulses generated by the first UWB BAN node device102-1.FIG.2Bdepicts time-domain plot204of UWB mono-cycle pulses generated by the second UWB BAN node device102-2.FIG.2Cdepicts time-domain plot206of UWB mono-cycle pulses generated by the third UWB BAN node device102-3.FIG.2Ddepicts time-domain plot208of UWB mono-cycle pulses generated by the fourth UWB BAN node device102-4.

Further, the frequency-domain plots (or spectral plots) of UWB mono-cycle pulses generated by the UWB BAN node devices are shown inFIGS.3A-3D. In particular,FIG.3Adepicts a frequency-domain plot302of UWB mono-cycle pulses generated by the first UWB BAN node device102-1.FIG.3Bdepicts a frequency-domain plot304of UWB mono-cycle pulses generated by the second UWB BAN node device102-2.FIG.3Cdepicts a frequency-domain plot306of UWB mono-cycle pulses generated by the third UWB BAN node device102-3.FIG.3Ddepicts a frequency-domain plot308of UWB mono-cycle pulses generated by the fourth UWB BAN node device102-4.

Referring back toFIG.1B, according to an aspect, the control node device104may receive the UWB signals transmitted from the plurality of UWB BAN node devices102-(1-N). Due to channel-induced impairments, the received UWB signals at the control node device104may be distorted. According to an aspect, upon receiving the UWB signals, the control node device104may encode the UWB signals using the SAC-OCDMA encoder108. The CW laser array114of the SAC-OCDMA encoder108may generate multiple wavelengths that may be used to encode the UWB signals. In an example, CW laser array114may generate two wavelengths for each of the UWB signals. Accordingly, for the first UWB BAN node device102-1, the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4, CW laser array114may generate total eight wavelengths at the same power level at its output port. In an example, these eight wavelengths are centered at λ1=1552.524 nm, λ2=1551.720 nm, λ3=1550.918 nm, λ4=1550.116 nm, λ5=1549.315 nm, λ6=1548.514 nm, λ7=1547.715 nm, and λ8=1546.916 nm. A combined spectrum400of the eight wavelengths generated through the CW laser array114is shown inFIG.4.

According to an aspect, the control node device104may modulate the encoded UWB signals using an on-off keying (OOK) scheme. In an aspect, the control node device104may modulate the encoded UWB signals using the plurality of MZMs112-(1-M). In an example, the plurality of MZMs112-(1-M) may include at least four MZMs. As shown inFIG.1B, the four MZMs include a first MZM112-1, a second MZM112-2, a third MZM112-3, and a fourth MZM112-4. According to an aspect, the BAN architecture100may include any number of MZMs.

The control node device104may combine the modulated UWB signals into an optical signal using the optical coupler110. The control node device104may combine the modulated UWB signals into the optical signal based on a double-weight zero cross-correlation (DW-ZCC) code scheme for example. Since the CW laser array114generates eight distinct wavelengths that are 0.8 nm apart for example, therefore, the optical coupler110can be used as an encoder to combine the specific wavelength in reference to the DW-ZCC code scheme. For example, for the first UWB BAN node device102-1, λ1=1552.524 nm and λ2=1551.720 nm are combined to translate the binary “1s” in the DW-ZCC code scheme into spectral representation, as shown in Table 1 (described later). After the encoding process, each “1” in the patient's physiological data is represented by a combination of two carriers centered as per the DW-ZCC code scheme. Consequently, the efficiency of the BAN architecture100is increased with added benefits of built-in security to eavesdropping. In the same way, the UWB signals from the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4are encoded using the DW-ZCC code scheme and then modulated with their respective patient physiological data signals as described earlier for the first UWB BAN node device102-1. The full-width at half-maximum (FWHM) of the UWB mono-cycle pulses of each UWB BAN node device at the output of the MZMs after the OOK modulation is around 125 ps. All four encoded optical signals after the OOK modulation are combined using the optical coupler110, as shown inFIG.1B.

The DW-ZCC code scheme is developed by considering three performance parameters of DW-ZCC which include code length (L), hamming weight (W), and cross-correlation (Cmax) between the adjacent codes represented by X and Y. The cross-correlation can be defined mathematically using Equation (1) provided below.

Cmax=Σi=1L⁢xi⁢yi=0.(1)

In Equation (1), X and Y are two adjacent code words, where X=x1, x2. . . xLand Y=y1, y2. . . yL. Also, xiand yiare bit values of respective code sequences.

The basic matrix with U code sequences of length L can be mathematically represented as Equation (2).

ZB=[11000000001100000000110000000011]U×L,(2)
where U represents the number of nodes.

From the basic matrix ZB, a large number of nodes can be accommodated using a simple mapping technique, such as Equation (3).

ZB=[ZB00ZB]8×16.(3)

Table 1 shows the DW-ZCC code scheme with U=4 and W=2, where PoS represent the position of “1” in each code sequence. The DW-ZCC code scheme is constructed with a reduced weight (W=2) to decrease the number of filters and evaluate the feasibility of the BAN architecture100in terms of implementational complexity and cost. In addition, a highly acknowledged direct detection technique can be used to recover the intended spectrum with desired correlation properties, thereby eliminating the need for an extra arrangement in the SAC-OCDMA encoder108.

It can be observed that there are no overlapping bits between the adjacent codes and throughout the ZB code matrix. Moreover, the association of the number of nodes and weight yields the total code length as Lt=U×L. For ease of representation, the first UWB BAN node device102-1, the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4are abbreviated to Node #1, Node #2, Node #3, and Node #4, respectively, in Table 1.

TABLE 1DW-ZCC code scheme (U = 4, W = 2 )WavelengthsNodesλ1λ2λ3λ4λ5λ6λ7λ8PositionsNode#111000000PoS1= [1, 2]Node#200110000PoS1= [3, 4]Node#300001100PoS1= [5, 6]Node#400000011PoS1= [7, 8]

To determine an efficient structure of the SAC-OCDMA encoder108, and to recover the intended spectrum with desired correlation properties, the correlation between code sequences of the DW-ZCC code scheme may be observed. It is evident from Table 1 that no overlapping bits exist between the codes. Therefore, correlation properties for the DW-ZCC code scheme can be mathematically represented by Equation (4) provided below.

Cmax=Σi=1L⁢Zx(i)⁢Zy(i)={W;x=y,0;x≠y},(4)
where, Zx(i) and Zy(i) denote the ithelement of the X and Y code sequences, respectively. It can be observed that zero cross-correlation exists between code sequences of the DW-ZCC code scheme. Therefore, direct detection can be adapted to recover the intended spectrum with maximum auto and minimum cross-correlation. In addition, the position of “1s” in the DW-ZCC code scheme exists in pairs, significantly simplifying the implementation of the SAC-OCDMA encoder108along with the allocation of the desired spectrum.

According to an aspect, the control node device104may include an optical amplifier (OA)140which amplifies the combined optical signal output from the optical coupler110. The amplified combined optical signal can be transmitted to the remote node device106through a free space optics (FSO) link150. In an example, the FSO link150may be of 0.5 km length. In some aspects, the control node device104may transmit the amplified combined optical signal to the remote node device106by a transmitter telescope (not shown). In an example, the total power radiated by the transmitter telescope in free space is around 30 dBm. In an example, the transmitter telescope may be connected to the control node device104through a single-mode fiber (SMF)134. In an example, the SMF134may have a length of 3.5 m.

In an aspect, the remote node device106may be configured to receive the amplified combined optical signal transmitted from the control node device104. The amplified combined optical signal can be received by a receiver telescope (not shown). In an example, the receiver telescope may be connected to the remote node device106through an SMF136. In an example, the SMF136may have a length of 3.5 m. The transmitter and receiver telescopes may have parameters similar to the commercial model #M1-10GE, manufactured by FSO Artolink as shown in Table 2.

TABLE 2Parameters of the transmitter and receiver telescopes (Model# M1-10GE,Manufactured by FSO Artolink)Sr. NoParametersValues1Diameter of transmitter telescope5cm2Diameter of receiver telescope20cm3Transmitter telescope aperture14Receiver telescope aperture15MaterialGRIN lens6Maximum transmission speed1.5Gbps7Operating wavelength1550nm8Maximum working distance2km

The amplified combined optical signal may be impaired by turbulence and attenuation from the atmosphere. According to an aspect, a Log-normal channel model may be used to model the atmospheric turbulence between the control node device104and the remote node device106. The Log-normal channel model may be generally implemented for clear sky FSO links, where the turbulence is weak. In an example, the values of the refractive index structure parameter and atmospheric attenuation used are chosen as 5×10−16and 5 dB/km, respectively. The Log-normal channel model is described in greater detail later in the disclosure.

Further, the remote node device106may be configured to decode the amplified combined optical signal using the SAC-OCDMA decoder116. The amplified combined optical signal can be input to SAC-OCDMA decoder116through the SMF136. In an example, the WDM de-multiplexer118may de-multiplex the amplified combined optical signal into a plurality of de-multiplexed optical signals, such as λ1-λ8inFIG.1B. The plurality of de-multiplexed optical signals is input to the plurality of optical couplers120-(1-O). Each optical coupler of plurality of optical couplers120-(1-O) may be associated with a respective one of the UWB signals and may be configured to combine wavelengths of the de-multiplexed optical signal corresponding to the respective one of the UWB signals. For example, as shown inFIG.1B, λ1and λ2are combined by a first optical coupler120-1and input to a first PIN photo-detector122-1, λ3and λ4are combined by a second optical coupler120-2and input to a second PIN photo-detector122-2, λ5and λ6are combined by a third optical coupler120-3and input to a third PIN photo-detector122-3, and λ7and λ8are combined by a fourth optical coupler120-4and input to a fourth PIN photo-detector122-4.

In an aspect, since the DWZCC code scheme has zero cross-correlation between adjacent codes, therefore, the highly acknowledged direct detection scheme can be adapted to recover the intended spectrum. The filter arrangement in the WDM de-multiplexer118may be utilized to receive the desired spectrum, as shown inFIG.1B. The technique significantly simplifies the overall BAN architecture100with the added benefit of receiving the intended spectrum with maximum auto and minimum cross-correlation.

The remote node device106may be configured to convert the decoded optical signal into an electrical signal. The decoded optical signal is converted into the electrical signal through one or more of the plurality of PIN photo-detectors122-(1-P), the plurality of DC block circuits124-(1-Q), the plurality of electrical amplifiers126-(1-R), the plurality of electrical splitters128-(1-S), and the plurality of electrical low pass filters130-(1-T). As shown inFIG.1B, the plurality of PIN photo-detectors122-(1-P) may include at least a first PIN photo-detector122-1, a second PIN photo-detector122-2, a third PIN photo-detector122-3, and a fourth PIN photo-detector122-4. The plurality of DC block circuits124-(1-Q) may include at least a first DC block circuit124-1, a second DC block circuit124-2, a third DC block circuit124-3, and a fourth DC block circuit124-4. The plurality of electrical amplifiers126-(1-R) may include at least a first electrical amplifier126-1, a second electrical amplifier126-2, a third electrical amplifier126-3, and a fourth electrical amplifier126-4. The plurality of electrical splitters128-(1-S) may include a first electrical splitter128-1, a second electrical splitter128-2, a third electrical splitter128-3, and a fourth electrical splitter128-4. The plurality of electrical low pass filters130-(1-T) may include a first electrical low pass filter130-1, a second electrical low pass filter130-2, a third electrical low pass filter130-3, and a fourth electrical low pass filter130-4.

According to an aspect, the plurality of PIN photo-detectors122-(1-P) may covert the optical signal into the electrical signal. As zero cross-correlation exists between adjacent codes, therefore, no multiple access interference and accompanying optical beat interference is generated at the plurality of PIN photo-detectors122-(1-P) during the conversion of the optical signal to the electrical signal, significantly elevating the quality of the signal. In an example, photo-detected UWB mono-cycle pulses of the first UWB BAN node device102-1may be generated at the output of the first PIN photo-detector122-1, photo-detected UWB mono-cycle pulses of the second UWB BAN node device102-2may be generated at the output of the second PIN photo-detector122-2, photo-detected UWB mono-cycle pulses of the third UWB BAN node device102-3may be generated at the output of the third PIN photo-detector122-3, and photo-detected UWB mono-cycle pulses of the fourth UWB BAN node device102-4may be generated at the output of the fourth PIN photo-detector122-4.

FIGS.5A-5Ddepict time-domain plots of the photo-detected UWB mono-cycle pulses detected at the output of the plurality of PIN photo detectors, according to aspects of the present disclosure. In particular,FIG.5Adepicts time-domain plot502of the photo-detected UWB mono-cycle pulses detected at the output of the first PIN photo-detector122-1.FIG.5Bdepicts time-domain plot504of the photo-detected UWB mono-cycle pulses detected at the output of the second PIN photo-detector122-2.FIG.5Cdepicts time-domain plot506of the photo-detected UWB mono-cycle pulses detected at the output of the third PIN photo-detector122-3.FIG.5Ddepicts time-domain plot508of photo-detected UWB mono-cycle pulses detected at the output of the fourth PIN photo-detector122-4.

According to an aspect, the photo-detected UWB mono-cycle pulses of each UWB BAN node device obtained at the output of the plurality of PIN photo-detectors122-(1-P) may be passed through the plurality of DC block circuits124-(1-Q) to remove DC offset and then amplified using the plurality of electrical amplifiers126-(1-R). The amplified signal is self-mixed, resulting in the conversion of the patient physiological data from UWB mono-cycle pulses to Gaussian pulses by removal of the negative cycle due to multiplication. The resulting electrical signal can be then low pass filtered using the plurality of electrical low pass filters130-(1-T) and forwarded to a bit rate error (BER) estimator (not shown) for BER estimation. The remote node device106may analyze the physiological data of the patient based on the electrical signal. In an aspect, the physiological data of the patient can be analyzed based on the electrical signal being input to the BER estimator. The summary of major simulation parameters for the setup ofFIG.1Bis shown in Table 3.

TABLE 3Major simulation parametersSr. NoParametersValues1Bit rate (per UWB BAN node device)30Mbps2Transmitter telescope diameter5cm3Receiver telescope diameter20cm4Beam divergence2mrad5Length of FSO link0.5km6Length of each SMF spool3.5m7Refractive index structure parameter5 × 10−168Responsitivity of PIN photo-detector0.9A/W9Optical amplifier gain30dB10Optical amplifier noise figure4dB11Electrical amplifier gain10dB

According to an aspect of the present disclosure, the BER estimator may evaluate the BER of the electrical signal received by an intended subscriber of the BAN architecture100. To evaluate the BER of the electrical signal, a Log-normal channel model may be utilized to determine the signal-to-noise ratios (SNRs) for back-to-back (BTB) as well as for turbulence conditions. In an example, to determine the SNRs, only those noise contributors may be considered that are being added between the SAC-OCDMA encoder108and the plurality of PIN photo-detectors122-(1-P), while the simulation results are taken by considering all noise contributors between the plurality of UWB BAN node devices102-(1-N) and the plurality of PIN photo-detectors122-(1-P).

Further, the FSO link150used by the control node device104to transmit the combined optical signal to the remote node device106may induce mainly two types of impairments known as attenuation and atmospheric turbulence. Atmospheric turbulence is the consequence of variations in the atmospheric temperature and pressure along the path of the optical signal. It is a major cause of optical signal degradation and results in random variations in signal irradiance, commonly known as intensity scintillation. Various statistical channel models may be implemented to consider the effect of attenuation and atmospheric turbulence on the optical signal. Some of the most commonly used channel models to estimate the effects of atmospheric turbulence on the optical signals include, but are not limited to, the negative exponential, K-distribution, Log-normal distribution, Log-normal-Rician, and Gamma-Gamma channel model. To characterize weak turbulence conditions of a clear sky link, the Log-normal distribution is employed. The probability density function of received light intensity I following a planar wave propagation in terms of variance of log-amplitude fluctuations may be mathematically represented by Equation (5) provided below.

pI(I)=12⁢I⁢2⁢π⁢σx2⁢exp[-ln(I/IO)28⁢σx2],(5)
where σx2=0.307 Cn2k7/6L11/6, L is the FSO link length in kilometers, k=2π/λ is the wave number, and Cn2represents the refractive index structure parameter whose values vary from 10−17to 10−12for weak turbulence to strong turbulence, respectively. In an example, even for a specific link, the refractive index structure parameter can vary over time due to the complex dynamics of atmospheric conditions.

According to an aspect, the SNR may be determined as a ratio of the average desired photo-current Ibreceived by the intended subscriber to the power of different noise sources generated throughout the BAN architecture100.

SNR=[Ib2ibn2].(6)

The average desired photo-current in the Equation (6) can also be mathematically represented as:

Ib=ℜ⁢bWm⁢Psr,(7)
where b∈{0, 1} is value of the bit that represents the transmission of binary 1 or 0 by the intended user. Psrrepresents the power per chip at the receiving end and is equivalent to

Ptx⁢D2⁢e-α⁢YN⁡(θ⁢d)2,
where Ptxis the transmitted power, D is the aperture diameter of the receiving telescope, α is the atmospheric attenuation, d is the distance between the transmitter telescope and the receiver telescope, and θ is the beam divergence.

In the Equation (7),is the responsivity of the PIN photo-detector that is used to convert the optical signal into the electrical domain. Further, Wmrepresents power units in the number of chips absorbed by the PIN photo-detector. Furthermore, Wm=W which indicates that maximum power units in the recovered spectrum is absorbed by the PIN photo-detector. The variance of the total noise power for the BAN architecture100may be determined as the sum of noise sources generated throughout the BAN architecture100that primarily includes optical beat interference iobn, relative intensity noise irn, shot noise isn, and thermal noise itn.

ibn2=iobn2+irn2+isn2+itn2.(8)

As direct detection technique recovers the intended spectrum, therefore, only the desired pulses will hit the PIN photo-detector. Moreover, cross-correlation between the adjacent codes of the DW-ZCC code scheme is equal to 0, therefore, the value of iobn2=0. Further, relative intensity noise (RIN) is generated. Moreover, all subscribers can cause cross-talk with the desired signal. Therefore, the power of the RIN with Wm=W can be mathematically represented as:

irn2=RN⁡(bWPsr+xPc)2⁢Be,(9)
where, RN is the noise factor with a typical value between −130 and −160 dBHz−1, Berepresents the electrical bandwidth, Pcdenotes the optical power in the cross-talk pulses, and x is an event of the interfering pulses from the possible subscribers out of U-1 that transmits bit “1”. The average value of x when the number of interfering subscribers that are sending bit “1” at every chip is equal and can be represented as:

x=Wm2(U-1)2⁢L.(10)

In an aspect, the haphazard nature of the photons that are incident upon the PIN photo-diode generates random electrons that result in fluctuation of the photo-current. This phenomenon generates shot noise that is proportional to the incident current times 2EBe. Mathematically, the shot noise can be represented as:

isn2=2E⁡(bWm⁢Psr+xPc)⁢Be.(11)
where E is the electron charge. Since direct detection at the intended subscriber recovers non-overlapping spectrum of the DW-ZCC code scheme, therefore, Pc=0 as no cross-talk is observed between the intended and interfering subscriber at the receiving photo-diode. Consequently, the value of isn2becomes:

isn2=2EbWm⁢Psr⁢Be.(12)

The thermal noise generated at the receiving photo-diode of the intended subscriber can be mathematically represented as:

itn2=4⁢KB⁢TBeRL,(13)
where T, KB, and RLrepresent the temperature, Boltzmann constant, and load resistance, respectively. The total variance of the noise power becomes:

ibn2=irn2+isn2+itn2.(14)

If the decision of the received bit is carried out by comparing the total current of the received signal with a threshold current IT, then the BER of the received optical signal can be calculated as:

BERO⁢(I)=Q⁢(I1-I0in⁢1+in⁢0),(15)
where I1and in1is the total signal current and noise power for bit “1”, and I0and in0is the total signal current and noise power for bit “0”, respectively. The total BER of the encoded signal that is transmitted over the Log-normal turbulent channel can be mathematically represented as:

BER=∫0∞BER0⁢(I)⁢pI(I)⁢dI,(16)
where, pI(I) is the probability density function of the Log-normal channel that is used under weak turbulence conditions to model the intensity fluctuations of the received signal at the PIN photo-detector. The BER in Equation (16) is used to calculate the performance of the BAN architecture100, in terms of quality of the received signal at the intended photodiode.

EXAMPLES AND EXPERIMENTS

The following examples are provided to illustrate further and to facilitate the understanding of the present disclosure.

Experimental Data and Performance Analysis

A) BER Performance

The UWB signals received at the remote node device106after being transmitted from the control node device104and propagation through the Log-normal channel model are analyzed for BER performance. The eye-diagrams of the Gaussian-shaped electrical signal at the output of the electrical bandpass filters, as shown inFIG.1B, are used to statistically calculate the BER. The optical power of the signals received at the PIN photo-detectors is varied with the help of an optical attenuator to observe the effect on the BER of the UWB mono-cycle pulses. Apart from turbulence, haze and rain-induced atmospheric attenuations are major detrimental effects in the FSO links. Light haze, heavy haze, light rain, and heavy rain can induce atmospheric attenuation of different values.

The values of atmospheric attenuation are chosen in the range of 5-35 dB/km, which covers most of the weather conditions.FIGS.6A-6Dshow the BER versus received optical power plots for UWB BAN node devices obtained at different values of atmospheric attenuation while considering weak turbulence regime which is specific to the Log-normal channel model. InFIGS.6A to6D, Node-1 represents the first UWB BAN node device102-1, Node-2 represents the second UWB BAN node device102-2, Node-3 represents the third UWB BAN node device102-3, and Node-4 represents the fourth UWB BAN node device102-4. In particular,FIG.6Ashows the BER versus received optical power plot602for the first UWB BAN node device102-1, the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4for the back-to-back (BTB) case.FIG.6Bshows the BER versus received optical power plot604for the first UWB BAN node device102-1, the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4for the atmospheric attenuation at 5 dB/km.FIG.6Cshows the BER versus received optical power plot606for the first UWB BAN node device102-1, the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4for the atmospheric attenuation at 20 dB/km.FIG.6Dshows the BER versus received optical power plot608for the first UWB BAN node device102-1, the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4for the atmospheric attenuation at 35 dB/km.

Receiver sensitivity is defined as the minimum optical power required to achieve a BER of 10−9. Due to small difference in values of receiver sensitivity of UWB BAN node devices, BER plots for the first UWB BAN node device102-1can be considered as an example. Therefore, the minimum value of receiver sensitivity for the BTB case of the first UWB BAN node device102-1is around −21.8 dBm. The sensitivity becomes −20.3 dBm for αatm=5 dB/km, resulting in a power penalty of around 1.5 dB. Furthermore, the minimum receiver sensitivity of the first UWB BAN node device102-1is around −17.2 dBm for αatm=35 dB/km, resulting in a power penalty of around 2 dB. The BER plots602,604,606, and608show that the receiver sensitivities are degraded when the value of atmospheric attenuation is increased. Small variations in receiver sensitivity are observed among the first UWB BAN node device102-1, the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4. Overall, the first UWB BAN node device102-1, the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4provide acceptable BER values indicating the suitability of the BAN architecture100for employment at healthcare centers.

To further elaborate the effect of FSO attenuation on the UWB BAN node devices,FIGS.7A-7Dshow eye-diagrams of the UWB BAN node devices at different values of atmospheric attenuation. InFIGS.7A to7D, Node-1 represents the first UWB BAN node device102-1, Node-2 represents the second UWB BAN node device102-2, Node-3 represents the third UWB BAN node device102-3, and Node-4 represents the fourth UWB BAN node device102-4. In particular,FIG.7Ashows eye diagrams702for the first UWB BAN node device102-1, the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4for the back-to-back (BTB) case.FIG.7Bshows eye diagrams704for the first UWB BAN node device102-1, the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4for the atmospheric attenuation at 5 dB/km.FIG.7Cshows eye diagrams706for the first UWB BAN node device102-1, the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4for the atmospheric attenuation at 20 dB/km.FIG.7Dshows eye diagrams708for the first UWB BAN node device102-1, the second UWB BAN node device102-2, the third UWB BAN node device102-3, and the fourth UWB BAN node device102-4for the atmospheric attenuation at 35 dB/km.

It may be observed that the opening of the eye reduces and amplitude variation increases on increasing the value of atmospheric attenuation from 5 to 35 dB/km.

Table 4 illustrates a performance of the BAN architecture100in comparison to conventional arts. It may be observed from Table 4 that the BAN architecture100outperforms the conventional arts on the basis of various factors, such as data rate, FSO range, and security. A dash “-” in certain rows of Table 4 represents that the information about this parameter is not provided in the particular study.

TABLE 4Comparison of major results of the BAN architecture with resultsof the past related studiesType ofFSOCostStudynodeData raterangeSecurityanalysisAIR1Mbps5m—NoBIR14.3Mbps1.5mOCDMANoCLED4.2Mbps5m—NoDLED—Walsh codesNoELED—1.5m—NoPresentUWB30Mbps0.5kmSAC-YesDisclosureOCDMA

Study A, which was described in “Performance evaluation of wireless optical communication for mobile body area network scenario with blocking effects” that was published on IET Optoelectronics, vol. 9, no. 5, pp. 211-217, 2015, describes performance evaluation of wireless optical communication for mobile BAN scenario with blocking effects. Study B, which was described in “Optical wireless links as an alternative to radio-frequency for medical body area networks” that was published on IEEE Journal on Selected Areas in Communications, vol. 33, no. 9, pp. 2002-2010, 2015, describes optical wireless links as an alternative to radio-frequency for medical BANs. Study C, which was described in “Investigation of wireless optical technology for communication between on-body nodes” that was published on 2nd IEEE international workshop on optical wireless communications (IWOW), pp. 79-83, 2013, discusses investigation of wireless optical technology for communication between on-body nodes. Study D, which was described in “A novel optical body area network for transmission of multiple patient vital signs” that was published on Ninth IEEE international conference on ubiquitous and future networks (ICUFN), pp. 542-544, 2017, describes optical BAN for transmission of multiple patient vital signs. Study E, which was described in “Patient mobility support for indoor non-directed optical body area networks” that was published on Sensors, vol. 19, no. 10, pp. 2297-2310, discusses about patient mobility support for indoor non-directed optical BANs.

B) Cost Analysis

The idea of deploying FSO links instead of the optical fiber (OF) media is based upon reduced deployment cost and lower maintenance cost along with high flexibility, mobility, and lower deployment time. A major part of the deployment cost for the OF media is spent on trenching between the transmitter and receiver modules, which requires a relatively large number of specialized laborers to dig the trench and lay the optical fiber media. Furthermore, trenches are prone to fiber cuts or breaks owing to the continuous development of surrounding infrastructure. On the contrary, the employment of an FSO link between the transmitter and receiver modules introduces a certain level of simplicity and reduction in deployment and maintenance costs. Cost of FSO links can be as low as ⅕ times of the OF based networks. However, such figures are subject to span and the number of subscribers in the network. To demonstrate the feasibility of FSO links as compared to OF media in terms of deployment cost and capital expenditure (CAPEX), the following Equations (17) and (18) can be used.

COF=(l×trenching)+(l×OF),(17)
where l represents the total length of trenching.

CFSO=Cost⁢of⁢FSO⁢transmitter/receiver⁢module.(18)

It may be observed from Equation (17) that the deployment cost for OF media encompasses the total amount spent on the trenching along with cost of OF media. On the other hand, deployment cost for FSO media as given in Equation (18) demonstrates that the overall cost is dependent on the cost of FSO transmitter and receiver modules only. With reference toFIG.1Bof the BAN architecture100, the employment of OF media or FSO link between the control node device104and the remote node device106may affect the overall cost for a fixed number of nodes. Therefore, the cost of the SAC-OCDMA encoder108and the SAC-OCDMA decoder116may not be considered in this analysis. Similarly, the installation cost is not considered owing to large variation among vendors. Table 5 shows the overall deployment cost for both scenarios by considering the costs of trenching, OF, and FSO modules as USD 1000, USD 25, and USD 500, respectively.

TABLE 5CAPEX for both scenarios corresponding to different network spansCAPEX($)Sr. NoNetwork block0.5 km1 km1.5 km2 km1OF512.51025155020502FSO500500500500

Table 5 shows the comparison between the network blocks of interest including OF media and FSO link over a span of 0.5, 1, 1.5, and 2 km. It can be observed that the CAPEX for the OF media increases with an increase in the length of the link. On the contrary, the cost of the FSO link remains the same over the entire span. Thus, it can be concluded that the FSO link is a viable option for the deployment of a small span network with relatively high data rate requirements. Furthermore, deployment of the FSO link not only minimizes the cost but also provides a certain level of simplicity in installation and maintenance costs that can be traded—of with a slight increase in CAPEX for smaller span networks. Therefore, the BAN architecture100provides good BER results with added advantages of low complexity, low cost, and security.

Accordingly, UWB over FSO link is implemented for OBANs to take advantage of the high bandwidth offered by the UWB signals and the FSO link. Due to their broad spectral width, the UWB signals are less prone to EMI which is a major issue in environments composed of multiple electrical components. Furthermore, EMI between UWB BAN node devices and medical equipments as well as RF exposure of the UWB BAN node devices to human body is reduced by employing low transmit power UWB wireless technology. The security of the FSO link is further enhanced by implementing the SAC-OCDMA encoder108with the help of multiple wavelengths generated by the CW laser array114.

The BAN architecture100can be employed for the implementation of e-health and telemedicine platforms in all kinds of assisted living facilities and hospitals. Further, simulations are performed using the commercial tool known as OptiSystem. OptiSystem software is the latest and most powerful commercial design tool that enables the system designers to plan, test, and simulate almost every type of optical link in the physical layer of optical network. It offers optical communication system design and planning from component to system level, and visually presents analysis and scenarios.

In an example, the application of the BAN architecture100is best suited in old-age homes, where elder citizens having multiple chronic diseases are living. The application scenario of the BAN architecture100is shown inFIG.8. Multiple patients with limited mobility inhabit in rooms having dimensions of 10 m×8 m situated in an old-age home, as shown inFIG.8. Each patient is equipped with four on-body UWB BAN node devices (for example, a first UWB BAN node device802, a second UWB BAN node device804, a third UWB BAN node device806, and a fourth UWB BAN node device808). The UWB BAN node devices may sense vital signs, such as pulse rate, body temperature, ECG, and EEG activities of the patients. The UWB BAN node devices transmit real-time data of the vital signs of the patients in the form of low PSD UWB signals towards control node devices located at a fixed position which is 8 m high from room floor. The UWB BAN node devices help in minimizing the EMI as well as the RF exposure to the patients. Each UWB BAN node device may transmit simultaneously at a different radio frequency to avoid the interference among UWB signals at control node devices. The optical signals of all control node devices are combined and then transmitted over the FSO link towards a remote healthcare center. The FSO link provides a cost-efficient solution to implement the BAN architecture as compared to RF and optical fiber-based BANs. As FSO links are prone to eavesdropping, privacy and multiple access in the transmission is achieved using SAC-OCDMA scheme which is implemented at the control node devices. The combined signal is decoded at the remote healthcare center. After optical to electrical conversion, the patient data is processed and interpreted by a nursing staff. The application scenario provides comprehensive and alternative e-health and tele-medicine platform for optimum nursing and look after of elder citizens living in old-age homes. The application scenario also minimizes the healthcare expenditures including permanent stationing of nursing staff at old-age homes, regular visits of physicians or elder citizens visits to cardiologist or neurologist, etc.

FIG.9illustrates a method900for the body area network (BAN) architecture100including the plurality of UWB BAN node devices102-(1-N), the control node device104, and the remote node device106, according to aspects of the present disclosure. The method900can be executed by computer hardware such as a controller1000inFIG.10, a data processing system1100inFIG.11, a processor1130inFIG.11andFIG.12, distributed components inFIG.13, and the like. The method900can also be implemented in software instructions, thus when the computer hardware executes the software instructions, the computer hardware performs the method900.

At step902, the method900includes measuring, by the plurality of UWB BAN node devices102-(1-N), real-time physiological data of a patient. According to an aspect, the plurality of UWB BAN node devices102-(1-N) may measure real-time physiological data of the patient.

At step904, the method900includes transmitting, from the plurality of UWB BAN node devices102-(1-N) to the control node device104, the physiological data using UWB signals. According to an aspect, the plurality of UWB BAN node devices102-(1-N) may transmit the physiological data to the control node device104using the UWB signals. In an example, each of the UWB signals operates at a different carrier frequency.

At step906, the method900includes encoding, by the control node device104, the UWB signals using the SAC-OCDMA encoder108. According to an aspect, the control node device104may encode the UWB signals using the SAC-OCDMA encoder108. The SAC-OCDMA encoder108includes the CW laser array114that generates two wavelengths for each of the UWB signals.

At step908, the method900includes modulating, by the control node device104, the encoded UWB signals using an on-off keying (OOK) scheme. According to an aspect, the control node device106may modulate the encoded UWB signals using the OOK scheme.

At step910, the method900includes combining, by the control node device104, the modulated UWB signals into an optical signal using the optical coupler110. According to an aspect, the control node device104may combine the modulated UWB signals into the optical signal using the optical coupler110. In an aspect, the modulated UWB signals are combined into the optical signal based on the DW-ZCC code scheme. The encoded UWB signals may be modulated using the plurality of MZMs112-(1-M).

At step912, the method900includes transmitting, from the control node device104to the remote node device106, the combined optical signal through the FSO link150. According to an aspect, the control node device104may transmit the combined optical signal to the remote node device106through the FSO link150. In an aspect, the combined optical signal may be transmitted by a transmitter telescope and received by a receiver telescope, the transmitter and receiver telescopes are connected to the control node device104and the remote node device106through respective single-mode fibers, respectively. In an aspect, the combined optical signal may be amplified using the optical amplifier140and then transmitted by the transmitter telescope to the remoted node device106.

At step914, the method900includes decoding, by the remote node device106, the combined optical signal using the SAC-OCDMA decoder116. According to an aspect, the remote node device106may decode the combined optical signal using the SAC-OCDMA decoder116. The SAC-OCDMA decoder116includes the WDM de-multiplexer118that de-multiplexes the combined optical signal. Further, the remote node device106includes the plurality of optical couplers120-(1-O). Each optical coupler is associated with a respective one of the UWB signals and is configured to combine the wavelengths of the de-multiplexed optical signal corresponding to the respective one of the UWB signals.

At step916, the method900includes converting, by the remote node device106, the decoded optical signal into an electrical signal. According to an aspect, the remote node device106may convert the decoded optical signal into the electrical signal. In an example, the decoded optical signal is converted into the electrical signal through a PIN photo-detector, a DC block circuit, an electrical amplifier, an electrical splitter, and an electrical low pass filter.

At step918, the method900includes analyzing, by the remote node device106, the physiological data of the patient based on the electrical signal. According to an aspect, the remote node device106may analyze the physiological data of the patient based on the electrical signal. The physiological data of the patient may be analyzed based on the electrical signal being input to a BER estimator.

FIG.10is an illustration of a non-limiting example of details of computing hardware used in the computing system, according to exemplary aspects of the present disclosure. InFIG.10, a controller1000is described which is a computing device (for example, BAN architecture100) and includes a CPU1001which performs the processes described above/below. The process data and instructions may be stored in memory1002. These processes and instructions may also be stored on a storage medium disk1004such as a hard drive (HDD) or portable storage medium or may be stored remotely.

Further, the claims are not limited by the form of the computer-readable media on which the instructions of the inventive process are stored. For example, the instructions may be stored on CDs, DVDs, in FLASH memory, RAM, ROM, PROM, EPROM, EEPROM, hard disk or any other information processing device with which the computing device communicates, such as a server or computer.

Further, the claims may be provided as a utility application, background daemon, or component of an operating system, or combination thereof, executing in conjunction with CPU1001and/or CPU1003and an operating system such as Microsoft Windows 7, UNIX, Solaris, LINUX, Apple MAC-OS and other systems known to those skilled in the art.

The hardware elements in order to achieve the computing device may be realized by various circuitry elements, known to those skilled in the art. For example, the CPU1001and/or CPU1003may be a Xenon or Core processor from Intel of America or an Opteron processor from AMD of America, or may be other processor types that would be recognized by one of ordinary skill in the art. Alternatively, the CPU1001and/or CPU1003may be implemented on an FPGA, ASIC, PLD or using discrete logic circuits, as one of ordinary skill in the art would recognize. Further, the CPU1001and/or CPU1003may be implemented as multiple processors cooperatively working in parallel to perform the instructions of the inventive processes described above.

The computing device inFIG.10also includes a network controller1006, such as an Intel Ethernet PRO network interface card from Intel Corporation of America, for interfacing with network1060. As can be appreciated, the network1060can be a public network, such as the Internet, or a private network such as an LAN or WAN network, or any combination thereof and can also include PSTN or ISDN sub-networks. The network1060can also be wired, such as an Ethernet network, or can be wireless such as a cellular network including EDGE, 3G and 4G wireless cellular systems. The wireless network can also be WiFi, Bluetooth, or any other wireless form of communication that is known.

The computing device further includes a display controller1008, such as a NVIDIA GeForce GTX or Quadro graphics adaptor from NVIDIA Corporation of America for interfacing with display1010, such as a Hewlett Packard HPL2445w LCD monitor. A general purpose I/O interface1012interfaces with a keyboard and/or mouse1014as well as a touch screen panel1016on or separate from display1010. General purpose I/O interface also connects to a variety of peripherals1018including printers and scanners, such as an OfficeJet or DeskJet from Hewlett Packard.

A sound controller1020is also provided in the computing device such as Sound Blaster X-Fi Titanium from Creative, to interface with speakers/microphone1022thereby providing sounds and/or music.

The general-purpose storage controller1024connects the storage medium disk1004with communication bus1026, which may be an ISA, EISA, VESA, PCI, or similar, for interconnecting all of the components of the computing device. A description of the general features and functionality of the display1010, keyboard and/or mouse1014, as well as the display controller1008, storage controller1024, network controller1006, sound controller1020, and general purpose I/O interface1012is omitted herein for brevity as these features are known.

The exemplary circuit elements described in the context of the present disclosure may be replaced with other elements and structured differently than the examples provided herein. Moreover, circuitry configured to perform features described herein may be implemented in multiple circuit units (e.g., chips), or the features may be combined in circuitry on a single chipset, as shown onFIG.11.

FIG.11shows a schematic diagram of a data processing system1100used within the computing system, according to exemplary aspects of the present disclosure. The data processing system1100is an example of a computer in which code or instructions implementing the processes of the illustrative aspects of the present disclosure may be located.

InFIG.11, the data processing system1100employs a hub architecture including a north bridge and memory controller hub (NB/MCH)1125and a south bridge and input/output (I/O) controller hub (SB/ICH)1120. The central processing unit (CPU)1130is connected to NB/MCH1125. The NB/MCH1125also connects to the memory1145via a memory bus, and connects to the graphics processor1150via an accelerated graphics port (AGP). The NB/MCH1125also connects to the SB/ICH1120via an internal bus (e.g., a unified media interface or a direct media interface). The CPU Processing unit1130may contain one or more processors and even may be implemented using one or more heterogeneous processor systems.

For example,FIG.12shows an example of the CPU1130. In the CPU1130, the instruction register1238retrieves instructions from the fast memory1240. At least part of these instructions is fetched from the instruction register1238by the control logic1236and interpreted according to the instruction set architecture of the CPU1130. Part of the instructions can also be directed to the register1232. In one aspects of the present disclosure the instructions are decoded according to a hardwired method, and in other aspects of the present disclosure the instructions are decoded according to a microprogram that translates instructions into sets of CPU configuration signals that are applied sequentially over multiple clock pulses. After fetching and decoding the instructions, the instructions are executed using the arithmetic logic unit (ALU)1234that loads values from the register1232and performs logical and mathematical operations on the loaded values according to the instructions. The results from these operations can be feedback into the register and/or stored in the fast memory1240. According to certain aspects of the present disclosures, the instruction set architecture of the CPU1130can use a reduced instruction set architecture, a complex instruction set architecture, a vector processor architecture, a very large instruction word architecture. Furthermore, the CPU1130can be based on the Von Neuman model or the Harvard model. The CPU1130can be a digital signal processor, an FPGA, an ASIC, a PLA, a PLD, or a CPLD. Further, the CPU1130can be an x86 processor by Intel or by AMD; an ARM processor, a Power architecture processor by, e.g., IBM; a SPARC architecture processor by Sun Microsystems or by Oracle; or other known CPU architecture.

Referring again toFIG.11, the data processing system1000can include that the SB/ICH1120is coupled through a system bus to an I/O Bus, a read only memory (ROM)1156, universal serial bus (USB) port1164, a flash binary input/output system (BIOS)1168, and a graphics controller1158. PCI/PCIe devices can also be coupled to SB/ICH11120through a PCI bus1162.

The PCI devices may include, for example, Ethernet adapters, add-in cards, and PC cards for notebook computers. The Hard disk drive1160and CD-ROM1156can use, for example, an integrated drive electronics (IDE) or serial advanced technology attachment (SATA) interface. In one aspects of the present disclosure the I/O bus can include a super I/O (SIO) device.

Further, the hard disk drive (HDD)1160and optical drive1166can also be coupled to the SB/ICH1120through a system bus. In one aspects of the present disclosure, a keyboard1170, a mouse1172, a parallel port1178, and a serial port1176can be connected to the system bus through the I/O bus. Other peripherals and devices that can be connected to the SB/ICH1120using a mass storage controller such as SATA or PATA, an Ethernet port, an ISA bus, an LPC bridge, SMBus, a DMA controller, and an Audio Codec.

Moreover, the present disclosure is not limited to the specific circuit elements described herein, nor is the present disclosure limited to the specific sizing and classification of these elements. For example, the skilled artisan will appreciate that the circuitry described herein may be adapted based on changes on battery sizing and chemistry, or based on the requirements of the intended back-up load to be powered.

The functions and features described herein may also be executed by various distributed components of a system. For example, one or more processors may execute these system functions, wherein the processors are distributed across multiple components communicating in a network. The distributed components may include one or more client and server machines, which may share processing, as shown byFIG.13, in addition to various human interface and communication devices (e.g., display monitors, smart phones, tablets, personal digital assistants (PDAs)). More specifically,FIG.13illustrates client devices including a smart phone1311, a tablet1312, a mobile device terminal1314and fixed terminals1316. These client devices may be commutatively coupled with a mobile network service1320via base station1356, access point1354, satellite1352or via an internet connection. Mobile network service1320may comprise central processors1322, a server1324and a database1326. Fixed terminals1316and mobile network service1320may be commutatively coupled via an internet connection to functions in cloud1330that may comprise security gateway1332, data center1334, cloud controller1336, data storage1338and provisioning tool1340. The network may be a private network, such as a LAN or WAN, or may be a public network, such as the Internet. Input to the system may be received via direct user input and received remotely either in real-time or as a batch process. Additionally, some aspects of the present disclosures may be performed on modules or hardware not identical to those described. Accordingly, other aspects of the present disclosures are within the scope that may be claimed.

The above-described hardware description is a non-limiting example of corresponding structure for performing the functionality described herein.

Obviously, numerous modifications and variations of the present disclosure are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the disclosure may be practiced otherwise than as specifically described herein.