METHOD AND APPARATUS FOR MULTI-PATH DELAY ESTIMATION

Abstract

Embodiments of the present disclosure provide a method performed by a communication device. The method includes obtaining, in frequency domain, channel estimation for a transmission unit for a channel between the communication device and another communication device, and calculating correlation coefficients for the transmission unit based on the channel estimation. The method also includes obtaining a delay spread for the channel from the calculated correlation coefficients.

Claims

1. A method performed by a communication device, comprising: obtaining, in frequency domain, channel estimation for a transmission unit for a channel between the communication device and another communication device; calculating correlation coefficients for the transmission unit based on the channel estimation; and obtaining a delay spread for the channel from the calculated correlation coefficients.

2. The method according to claim 1, wherein obtaining the delay spread further comprises: calculating a correlation ratio from the correlation coefficients; comparing the correlation ratio with a predetermined value; and obtaining the delay spread based on the comparison.

3. The method according to claim 1, wherein calculating the correlation coefficients comprises: calculating the correlation coefficients for one or more frequency bands respectively; and averaging the correlation coefficients over the one or more frequency bands.

4. The method according to claim 1, wherein the transmission unit comprises a Demodulation Reference Signal, DMRS, symbol.

5. The method according to claim 1, wherein the transmission unit comprises two or more Demodulation Reference Signal, DMRS, symbols; obtaining the channel estimation further comprises obtaining the channel estimation for each of the two or more DMRS symbols respectively; and calculating the correlation coefficients further comprises calculating correlation coefficients for each of the two or more DMRS symbols respectively and averaging the correlation coefficients over the two or more DMRS symbols.

6. The method according to claim 1, wherein the predetermined value is stored in a table.

7. The method according to claim 1, wherein the communication device is a terminal device and the another communication device is a network device; or the communication device is a network device and the another communication device is a terminal device.

8. A communication device, comprising: a processor and a memory, said memory containing instructions executable by said processor whereby said communication device is operative to: obtain, in frequency domain, channel estimation for a transmission unit for a channel between the communication device and another communication device; calculate correlation coefficients for the transmission unit based on the channel estimation; and obtain a delay spread for the channel from the calculated correlation coefficients.

9. The communication device according to claim 8, wherein the delay spread is obtained by: calculating a correlation ratio from the correlation coefficients; comparing the correlation ratio with a predetermined value; and obtaining the delay spread based on the comparison.

10. The communication device according to claim 8, wherein the correlation coefficients are calculated by: calculating the correlation coefficients for one or more frequency bands respectively; and averaging the correlation coefficients over the one or more frequency bands.

11. The communication device according to claim 8, wherein the transmission unit comprises a Demodulation Reference Signal, DMRS, symbol.

12. The communication device according to claim 8, wherein the transmission unit comprises two or more Demodulation Reference Signal, DMRS, symbols; obtaining the channel estimation further comprises obtaining the channel estimation for each of the two or more DMRS symbols respectively; and calculating the correlation coefficients further comprises calculating correlation coefficients for each of the two or more DMRS symbols respectively and averaging the correlation coefficients over the two or more DMRS symbols.

13. The communication device according to claim 8, wherein the predetermined value is stored in a table.

14. A non-transitory computer-readable medium having instructions stored thereon which, when executed on at least one processor, cause the at least one processor to carry out the method according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The disclosure itself, the preferable mode of use and further objectives are best understood by reference to the following detailed description of the embodiments when read in conjunction with the accompanying drawings, in which:

[0029] FIG. 1 illustrates a flowchart for a method 100 performed by a communication device according to embodiments of the present disclosure;

[0030] FIG. 2 illustrates an illustrative example of theoretical correlation coefficients calculated for four multi-path time delays;

[0031] FIG. 3 illustrates a communication device 300 according to embodiments of the present disclosure; and

[0032] FIG. 4 illustrates a communication device 400 according to embodiments of the present disclosure.

DETAILED DESCRIPTION

[0033] The embodiments of the present disclosure are described in detail with reference to the accompanying drawings. It should be understood that these embodiments are discussed only for the purpose of enabling those skilled persons in the art to better understand and thus implement the present disclosure, rather than suggesting any limitation on the scope of the present disclosure. Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present disclosure should be or are in any single embodiment of the disclosure. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present disclosure. Furthermore, the described features, advantages, and characteristics of the disclosure may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the disclosure may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the disclosure.

[0034] As used herein, the term “communication network” refers to a network following any suitable communication standards, such as new radio (NR), long term evolution (LTE), LTE-Advanced, wideband code division multiple access (WCDMA), high-speed packet access (HSPA), and so on. Furthermore, the communications between a terminal device and a network node/device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G), the second generation (2G), 2.5G, 2.75G, the third generation (3G), 4G, 4.5G, 5G communication protocols, and/or any other protocols either currently known or to be developed in the future.

[0035] The term “network node”, and or “network device” refers to any node/device in a communication network via which a terminal device accesses to the network and receives services therefrom. The network node or network device may refer to a base station (BS), an access point (AP), a multi-cell/multicast coordination entity (MCE), a controller, a station (STA) or any other suitable device in a wireless communication network. The BS may be, for example, a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), a next generation NodeB (gNodeB or gNB), a remote radio unit (RRU), a radio header (RH), a remote radio head (RRH), a relay, a low power node such as a femto, a pico, and so forth.

[0036] Yet further examples of the network node/device comprise multi-standard radio (MSR) radio equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, positioning nodes and/or the like. More generally, however, the network node/device may represent any suitable device (or group of devices) capable, configured, arranged, and/or operable to enable and/or provide a terminal device access to a wireless communication network or to provide some service to a terminal device that has accessed to the wireless communication network.

[0037] The term “terminal device” refers to any end device that can access a communication network and receive services therefrom. By way of example and not limitation, the terminal device may refer to a mobile terminal, a user equipment (UE), or other suitable devices. The UE may be, for example, a subscriber station, a portable subscriber station, a mobile station (MS) or an access terminal (AT). The terminal device may include, but not limited to, portable computers, image capture terminal devices such as digital cameras, gaining terminal devices, music storage and playback appliances, a mobile phone, a cellular phone, a smart phone, a tablet, a wearable device, a personal digital assistant (PDA), a vehicle, and the like.

[0038] The term “communication device” may refer to either a “terminal device” or a “network device”.

[0039] As used herein, the terms “first”, “second” and so forth refer to different elements. The singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises”, “comprising”, “has”, “having”, “includes” and/or “including” as used herein, specify the presence of stated features, elements, and/or components and the like, but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof. The term “based on” is to be read as “based at least in part on”. The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment”. The term “another embodiment” is to be read as “at least one other embodiment”. Other definitions, explicit and implicit, may be included below.

[0040] In the following, various embodiments of the present disclosure will be described with reference to the accompany figures.

[0041] FIG. 1 illustrates a flowchart for a method 100 performed by a communication device according to embodiments of the present disclosure.

[0042] The method starts at block 110, where the communication device obtains in frequency domain, channel estimation for a transmission unit for a channel between the communication device and another communication device.

[0043] In some embodiments, the transmission unit may comprise a Demodulation Reference Signal (DMRS) symbol. In the embodiment where the communication device is a terminal device, e.g. a UE, while the another communication device is a network device, e.g. an eNB or gNB, the DMRS is a DL DMRS. In the embodiment where the communication device is a network device, e.g. an eNB or gNB, while the another communication device is a terminal device, e.g. a UE, the DMRS is an UL DMRS.

[0044] In particular, the communication device may perform Least Square (LS) channel estimation on the received DMRS(s) to obtain raw frequency channel estimation result H.sub.raw, i.e. H.sub.raw(k)=Y.sub.DMRS(k)/X.sub.DMRS(k), where Y.sub.DMRS is the received DMRS in frequency domain; X.sub.DMRS is the transmitted DMRS in frequency domain, k refers to a sample index.

[0045] Then in block 120, the communication device calculates correlation coefficients for the transmission unit based on the channel estimation, e.g. H.sub.raw.

[0046] In an embodiment where the transmission unit comprises one DMRS symbol, the communication device receiving the DMRS symbol may calculate the channel correlation coefficients for given points (Δf), e.g. {circumflex over (R)}.sub.Hl (Δf) of Δf=1, 2, 3, for the DMRS symbol, where Δf=1 represents a minimum frequency distance of input samples for the channel estimation, Δf=2 represents 2 times of the minimum frequency distance, and Δf=3 represents 3 times of the minimum frequency distance.

[0047] In particular, the calculation of correlation coefficients is based on raw frequency channel estimation H.sub.raw for the DMRS symbol. As an example, if the whole bandwidth of the channel comprises one or more narrow bands (e.g. each narrow band having 2RBs), and there are 2*3=6 samples for channel estimation per narrowband per DMRS symbol, let b represent a narrowband index, then the correlation coefficients {circumflex over (R)}.sub.H,b(Δf) for this narrowband can be calculated as

[00005]$\begin{array}{cc}{\stackrel{.Math.}{R}}_{H,b}\left(\Delta f\right)=E\left[H_{\mathrm{raw}}\left(k\right)H_{\mathrm{raw}}^{*}\left(k+\Delta f\right)\right]=\frac{1}{N}\underset{k}{.Math.}{H}_{\mathrm{raw}}\left(k\right)H_{\mathrm{raw}}^{*}\left(k+\Delta f\right)& \left(2\right)\end{array}$

where k refers to the sample index and N is the total number of valid k with k satisfying 0≤k≤5 and 0≤k+Δf≤5. Thus, when Δf=1, then k=0, 1, 2, 3, 4 and N=5; when Δf=2, then k=0, 1, 2, 3 and N=4; when Δf=3, then k=0, 1, 2 and N=3. Please note that, the total sample number for channel estimation per narrowband per DMRS symbol is calculated as N.sub.b=N.sub.RB.sup.scg.Math.N.sub.dmrs.sup.RB, where N.sub.RB.sup.scg is the number of RBs per narrowband, such as “2” as described above, and N.sub.dmrs.sup.RB is the number of DMRS samples per RB per DMRS symbol, such as “3” as described above. Further, E[.] means average operation.

[0048] Further, for convenience of calculation and comparison, absolute values may be utilized. Namely,

[00006]${\stackrel{.Math.}{R}}_{H,b}\left(\Delta f\right)=.Math.E\left[H_{\mathrm{raw}}\left(k\right)H_{\mathrm{raw}}^{*}\left(k+\Delta f\right)\right].Math.=.Math.\frac{1}{N}\underset{k}{.Math.}{H}_{\mathrm{raw}}\left(k\right)H_{\mathrm{raw}}^{*}\left(k+\Delta f\right).Math.,$

where |.| means an absolute value operation.

[0049] In an embodiment where the whole bandwidth comprises several narrow bands, the communication device may average the channel correlation coefficients {circumflex over (R)}.sub.H,b(Δf) over all the narrow bands. That is,

[00007]${\stackrel{.Math.}{R}}_H\left(\Delta f\right)=\frac{1}{M}\underset{b=0}{\overset{M-1}{.Math.}}{\stackrel{.Math.}{R}}_{H,b}\left(\Delta f\right),$

where M is the total number of the narrow bands.

[0050] In an embodiment where the transmission unit comprises two or more DMRS symbols, the communication device may calculate the channel correlation coefficients for each DMRS symbol and then average the channel correlation coefficients over all of the two or more DMRS symbols.

[0051] Then in block 130, the communication device obtains a delay spread/multi-path delay for the channel from the calculated correlation coefficients.

[0052] In an embodiment, the communication device may obtain the delay spread by calculating a correlation ratio of the correlation coefficients, comparing the correlation ratio with a predetermined value, which may be stored in a table, and then obtaining the delay spread based on the comparison.

[0053] In an example where the correlation coefficients (which may be the averaged correlation coefficients) are calculated e.g. for three given points, i.e. Δf=(1,2,3), as {circumflex over (R)}.sub.H(1), {circumflex over (R)}.sub.H(2), and {circumflex over (R)}.sub.H(3), the communication device may calculate the correlation ratios of

[00008]$\begin{array}{cc}\frac{{\hat{R}}_H\left(3\right)}{{\hat{R}}_H\left(1\right)}\mathrm{and}\frac{{\hat{R}}_H\left(2\right)}{{\hat{R}}_H\left(1\right)},& \end{array}$

and then compare the calculated correlation ratios with some predetermined values. The predetermined values are calculated according to the existing theory or experience and stored in the form of a table.

[0054] For example, the predetermined values can be obtained by the following approach. Firstly, the correlation coefficients are calculated for different possible multi-path delays. Taking the three-dimensional MIMO channel defined in 3GPP 36.873 V12.7.0 as an example, three different multi-path time delays (τ.sub.max, τ.sub.rms)=(0.1 μs, 0.03 μs),(1.03 μs, 0.32 μs),(5.15 μs, 0.92 μs) can be used to calculate the correlation coefficients R.sub.f(Δf)(a correlation function of Δf, which is the distance between two frequency domain samplings) (representing any of {tilde over (R)}.sub.H(1), {tilde over (R)}.sub.H(2) and {tilde over (R)}.sub.H(3)) according to, but not limited to:

[00009]$R_f\left(\Delta f\right)=\frac{1-\exp \left(-{\tau }_{\max }\left(\frac{1}{{\tau }_{\mathrm{rms}}}+j2\pi \Delta f\right)\right)}{\left(1-\exp \left(-\frac{{\tau }_{\max }}{{\tau }_{\mathrm{rms}}}\right)\right)\left(1+j2\pi \Delta f{\tau }_{\mathrm{rms}}\right)}$

if p.d.f is

[00010]$\theta \left(\tau \right)=\frac{\exp \left(-\frac{\tau }{{\tau }_{\mathrm{rms}}}\right)}{{\tau }_{\mathrm{rms}}\left(1-\exp \left(-\frac{L}{{\tau }_{\mathrm{rms}}}\right)\right)}$

and τ∈[0,L], (2)

[0055] wherein L is the maximum delay. Then, for example, the correlation ratios of

[00011]$\begin{array}{cc}\frac{{\tilde{R}}_H\left(3\right)}{{\tilde{R}}_H\left(1\right)}\mathrm{and}\frac{{\tilde{R}}_H\left(2\right)}{{\tilde{R}}_H\left(1\right)}& \end{array}$

can be calculated and stored in a table as predetermined values.

[0056] FIG. 2 illustrates an example of theoretical correlation coefficients calculated for four multi-path time delays, i.e. (τ.sub.max, τ.sub.rms)=(0.1 μs, 0.03 μs), (0.51 μs, 0.167 μs), (1.03 μs, 0.32 μs) and (5.15 μs, 0.92 μs). In FIG. 2, the horizontal axis represents subcarriers and the vertical axis represents correlation coefficients. As shown, the correlation coefficient for the central subcarrier 100 is 1. The two black squares in each sub-figure of FIG. 2 show the theoretical correlation coefficients {tilde over (R)}.sub.H(1), {tilde over (R)}.sub.H(3) for two given points i.e. Δf=1 (one time of the DMRS subcarrier interval (i.e. 4 subcarriers)) and Δf=3 (three times of the DMRS subcarrier interval (i.e. 12 subcarriers)), respectively. For ease of illustration rather than limitation, only two points are used herein. Based on this figure, the theoretical

[00012]$\frac{{\tilde{R}}_H\left(3\right)}{{\tilde{R}}_H\left(1\right)}$

can be calculated and prestored.

[0057] For example, if the measured ratio

[00013]$\frac{{\hat{R}}_H\left(3\right)}{{\hat{R}}_H\left(1\right)}$

is smaller than the theoretical ratio

[00014]$\frac{{\tilde{R}}_H\left(3\right)}{{\tilde{R}}_H\left(1\right)}$

when τ.sub.rms=0.03 μs, then the multi-path delay may be estimated as τ.sub.rms=0.03 μs; otherwise, if the measured ratio

[00015]$\frac{{\hat{R}}_H\left(3\right)}{{\hat{R}}_H\left(1\right)}$

is smaller than the theoretical ratio

[00016]$\frac{{\tilde{R}}_H\left(3\right)}{{\tilde{R}}_H\left(1\right)}$

when τ.sub.rms=0.167 μs, then the multi-path delay may be estimated as τ.sub.rms=0.167 μs; otherwise, if the measured ratio

[00017]$\frac{{\hat{R}}_H\left(3\right)}{{\hat{R}}_H\left(1\right)}$

is smaller than the theoretical ratio

[00018]$\frac{{\tilde{R}}_H\left(3\right)}{{\tilde{R}}_H\left(1\right)}$

when τ.sub.rms=0.32 μs, then the multi-path delay may be estimated as τ.sub.rms=0.32 μs; otherwise, the multi-path delay may be estimated as τ.sub.rms=0.92 μs.

[0058] Correspondingly, τ.sub.max may be selected from the same set (τ.sub.max, τ.sub.rms) as τ.sub.rms.

[0059] If the correlation coefficients are available for more points and more than one correlation ratios may be calculated, then more than one multi-path delays τ.sub.rms,1 τ.sub.rms,2 . . . may be obtained based on the above method. Then the maximum value can be chosen as the final delay spread, i.e. τ.sub.rms=max (τ.sub.rms,1, τ.sub.rms,2, . . . ).

[0060] In another example, the communication device can calculate correlation ratios of

[00019]$\begin{array}{cc}\frac{{\hat{R}}_H\left(3\right)+{\hat{R}}_H\left(1\right)}{2{\hat{R}}_H\left(1\right)}\mathrm{and}\frac{{\hat{R}}_H\left(2\right)+{\hat{R}}_H\left(1\right)}{2{\hat{R}}_H\left(1\right)}& \end{array}$

after obtaining correlation coefficients {circumflex over (R)}.sub.H(1), {circumflex over (R)}.sub.H(2), and {circumflex over (R)}.sub.H(3) as above, and then compare such ratios with the predetermined values which may be calculated according to the existing theory or experience and stored in a table. For example, according to equation (2), theoretical correlation coefficients {tilde over (R)}.sub.H(1), {tilde over (R)}.sub.H(2) and {tilde over (R)}.sub.H(3) can be calculated and then

[00020]$\frac{{\tilde{R}}_H\left(3\right)+{\tilde{R}}_H\left(1\right)}{{\tilde{R}}_H\left(1\right)}\mathrm{and}\frac{{\tilde{R}}_H\left(2\right)+{\tilde{R}}_H\left(1\right)}{{\tilde{R}}_H\left(1\right)}$

can be obtained and stored. Based on the comparison, multi-path delays (τ.sub.max,1, T.sub.rms,1) and (τ.sub.max,2, T.sub.rms,2) are obtained. Then the maximum value can be chosen as the final delay spread, i.e. τ.sub.rms=max (τ.sub.rms,1, τ.sub.rms,2), and τ.sub.max may be selected from the same set as τ.sub.rms.

[0061] In a further example, the communication device can calculate correlation ratio of

[00021]$\begin{array}{cc}\frac{{\hat{R}}_H\left(3\right)+{\hat{R}}_H\left(1\right)}{2{\hat{R}}_H\left(1\right)}\mathrm{and}\frac{{\hat{R}}_H\left(2\right)+{\hat{R}}_H\left(1\right)}{2{\hat{R}}_H\left(1\right)}& \end{array}$

after obtaining correlation coefficients {circumflex over (R)}.sub.H(1), {circumflex over (R)}.sub.H(2), and {circumflex over (R)}.sub.H(3), and compare such ratios with the predetermined values which may be calculated according to the existing theory or experience and stored. For example, according to equation (2), theoretical correlation coefficients {tilde over (R)}.sub.H(1), {tilde over (R)}.sub.H(2) and {tilde over (R)}.sub.H(3) can be calculated and then

[00022]$\begin{array}{cc}\frac{{\tilde{R}}_H\left(3\right)+{\tilde{R}}_H\left(1\right)}{2{\tilde{R}}_H\left(1\right)}\mathrm{and}\frac{{\tilde{R}}_H\left(2\right)+{\tilde{R}}_H\left(1\right)}{2{\tilde{R}}_H\left(1\right)}& \end{array}$

can be obtained and stored. Based on the comparison, multi-path delays (τ.sub.max,1, τ.sub.rms,1) and (τ.sub.max,2, τ.sub.rms,2) are obtained. Then the maximum value can be chosen as the final delay spread, τ.sub.rms=max (τ.sub.rms,1, τ.sub.rms,2), and τ.sub.max may be selected from the same set as τ.sub.rms.

[0062] Please note that depending on different implementation, the number of points for which the correlation coefficients are calculated may be more or less than three. Two or more points are all feasible. However, use of the relatively less points may reduce complexity. In addition, with more points being used for calculation of correlation coefficients more correlation ratios may be calculated (also depending on implementation). Accordingly, more multi-path delays can be obtained for the delay spread estimation, and thus the accuracy may be improved.

[0063] In some embodiments, in order to enhance robustness and performance, more than two property values, e.g. two types of ratios, can be calculated and compared to the predetermined values.

[0064] Generally, all valid values of {circumflex over (R)}.sub.H(Δf) can be used to extract the characteristic of the theoretical frequency channel correlation function, including but not limited to slope, gradient, and reciprocal. Then the extracted characteristic can be compared with theoretical predetermined values for different time delays to obtain the actual time delay (e.g. the delay spread and/or the maximum delay).

[0065] Please note that the description of the above embodiments in relation to 5G NR is shown as an example. The concept and idea of the present disclosure can be more generally applied to other communication systems.

[0066] FIG. 3 illustrates a communication device 300 according to embodiments of the present disclosure. The communication device 300 may be a terminal device or a network device.

[0067] As illustrated, the communication device 300 comprises a processor 310 and a memory 320. The memory 320 contains instructions executable by the processor 310 whereby the communication device is operative to perform the method as described above in reference to FIG. 1.

[0068] In particular, the memory 320 contains instructions executable by the processor 310 whereby the communication device is operative to obtain, in frequency domain, channel estimation for a transmission unit for a channel between the communication device and another communication device, to calculate correlation coefficients for the transmission unit based on the channel estimation and to obtain a multi-path delay for the channel from the calculated correlation coefficients.

[0069] In an embodiment of the present disclosure, the multi-path delay may be obtained by calculating a correlation ratio from the correlation coefficients, comparing the correlation ratio with a predetermined value, which may be stored in a table, and then obtaining the delay spread based on the comparison.

[0070] In a further embodiment, the correlation coefficients may be calculated by calculating the correlation coefficients for one or more frequency bands respectively and averaging the correlation coefficients over the one or more frequency bands.

[0071] In a further embodiment, the transmission unit may comprise one or more DMRS symbols. In the embodiment that the transmission unit comprises two or more DMRS symbols, the communication device 300 may obtain the channel estimation for each of the two or more DMRS symbols respectively and then calculate correlation coefficients for each of the two or more DMRS symbols respectively and average the correlation coefficients over the two or more DMRS symbols.

[0072] Other embodiments of the present disclosure provide a computer-readable medium having instructions stored thereon. The instructions, when executed on at least one processor, cause the at least one processor to carry out the method as described above in reference to FIG. 1

[0073] FIG. 4 illustrates a communication device 400 according to embodiments of the present disclosure. The communication device 400 may be a terminal device or a network device.

[0074] As illustrated, the communication device 400 comprises a first obtaining module 410, a calculating module 420 and a second obtaining module 430. The first obtaining module 410 is configured to obtain, in frequency domain, channel estimation for a transmission unit for a channel between the communication device and another communication device. The calculating module 420 is configured to calculate correlation coefficients for the transmission unit based on the channel estimation. The second obtaining module 430 is configured to obtain a delay spread for the channel from the calculated correlation coefficients. The first obtaining module 410, the calculating module 420 and the second obtaining module 430 may be further configured to operate in accordance with the method as described with reference to FIG. 1.

[0075] In general, the various exemplary embodiments may be implemented in hardware or special purpose chips, circuits, software, logic or any combination thereof. For example, some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although the disclosure is not limited thereto. While various aspects of the exemplary embodiments of this disclosure may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

[0076] As such, it should be appreciated that at least some aspects of the exemplary embodiments of the disclosure may be practiced in various components such as integrated circuit chips and modules. It should thus be appreciated that the exemplary embodiments of this disclosure may be realized in an apparatus that is embodied as an integrated circuit, where the integrated circuit may comprise circuitry (as well as possibly firmware) for embodying at least one or more of a data processor, a digital signal processor, baseband circuitry and radio frequency circuitry that are configurable so as to operate in accordance with the exemplary embodiments of this disclosure.

[0077] It should be appreciated that at least some aspects of the exemplary embodiments of the disclosure may be embodied in computer-executable/readable instructions, such as in one or more program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types when executed by a processor in a computer or other device. The computer executable instructions may be stored on a computer readable medium such as a hard disk, optical disk, removable storage media, solid state memory, random access memory (RAM), etc. As will be appreciated by one of skill in the art, the function of the program modules may be combined or distributed as desired in various embodiments. In addition, the function may be embodied in whole or partly in firmware or hardware equivalents such as integrated circuits, field programmable gate arrays (FPGA), and the like.

[0078] The present disclosure includes any novel feature or combination of features disclosed herein either explicitly or any generalization thereof. Various modifications and adaptations to the foregoing exemplary embodiments of this disclosure may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings. However, any and all modifications will still fall within the scope of the non-limiting and exemplary embodiments of this disclosure.