Open AccessArticle

An Experimental Study of Radiated Energy from an Optical Fiber and the Potential for an Optical MIMO System

Hasan Farahneh

Jamal S. Rahhal

Dia I. Abualnadi

Ibrahim Mansour

Ahmad K. Atieh

and

Xavier Fernando

^4,*

Department of Electrical Engineering, The University of Jordan, Amman 11942, Jordan

Electrical Engineering Department, Zarqa University, Zarqa 13110, Jordan

Optiwave Systems Inc., Nepean, ON K2E 8A7, Canada

⁴

Department of Electrical and Computer Engineering, Toronto Metropolitan University, Toronto, ON M5B 2K3, Canada

Author to whom correspondence should be addressed.

Appl. Sci. 2025, 15(6), 2916; https://doi.org/10.3390/app15062916

Submission received: 28 January 2025 / Revised: 28 February 2025 / Accepted: 5 March 2025 / Published: 7 March 2025

(This article belongs to the Special Issue Signal Processing and Communication for Wireless Sensor Network)

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Abstract

Leaky feeders provide seamless and uniform signal coverage in confined spaces like tunnels, mines, and buildings. Their easy scalability and integration with modern systems, like Multiple Input Multiple Output (MIMO), make them ideal for environments requiring reliable and consistent connectivity. However, using optical fiber as a radiating cable has never been investigated before. This may seem infeasible at first sight. However, our experimental study shows otherwise. We measured light leaking from a bent optical fiber transmitter. We also derived closed-form formulas to describe the amount of leakage energy and found that this energy exponentially varies with the square of the curvature radius. This allows us to design an Optical Leaky Feeder (OLF) transmission system for the first time. Then, we analytically show that a slotted optical fiber can be used as a MIMO receiver. The proposed system can ensure reliable, high-quality signal distribution even in challenging environments like tunnels, industrial settings, and dense urban areas.

Keywords:

optical leaky feeder; MIMO; bending loss; optical fiber

1. Introduction

Fiber-optic technology has become an integral part of modern life, revolutionizing how we communicate, access information, and entertain ourselves. The ability of the fiber to transmit data as light pulses through strands of glass or plastic enables high-speed and high-capacity communication over long distances with minimal signal loss. In telecommunications, fiber optics serve as the backbone of global networks, facilitating rapid internet connections, clear voice calls, and high-definition video streaming. The superior bandwidth and reliability of fiber optics have been important in meeting the rapid and high demand for data transmission in our increasingly digital world [1].

Beyond telecommunications, fiber optics have applications in various fields. In medicine, they are used in imaging tools and minimally invasive surgical procedures. In the defense sector, fiber optics are employed for secure communication and sensing applications. Industries utilize fiber optics for precise measurements and data transmission in harsh environments [2].

The scalability and durability of fiber optic infrastructure further underscore its importance. With the capacity to support future technological advancements, fiber optics are considered a future-proof solution, capable of accommodating the growing data needs of society.

Bending loss, also known as macro-bending loss, occurs when an optical fiber is subjected to a curvature or bend that exceeds a critical radius, causing a portion of the guided light to escape from the fiber core. This phenomenon leads to the attenuation or loss of optical signal power, which can degrade the performance of fiber optic systems. This bending may occur for many reasons, such as tight bends when the fiber is bent at a radius smaller than its critical bending radius. The light rays in the core may no longer satisfy the total internal reflection condition, and escape into the cladding. Also, mechanical stress due to tight installations or environmental factors can lead to bending losses. Moreover, poor cable management or excessive twisting during installation can cause unwanted bends [3].

As everyone is aware, there is a massive scale of fiber cable usage in many places around the world, and the large size of the signals within fiber cables are well known. Since there is loss and leakage of signal energy within fiber cables, it is essential to seriously consider collecting this lost energy and utilize it for various purposes.

Many researchers have investigated fiber loss in their work. In [4], the authors found that it is challenging to calculate the macro-bending loss of an optical fiber when the bending radius is small, based on Marcuse’s theory and its derivative theories. The authors in [3] presented an enhanced model to accurately predict macro-bending losses and power fluctuations in single-mode optical fibers. By refining the existing theoretical frameworks, the authors offer a more precise tool for designing and optimizing fiber optic systems, particularly in scenarios involving tight bends. This advancement holds significant implications for improving the reliability and performance of fiber-based communication networks. A method for calculating transfer and loss coefficients in bent slab single-mode waveguides and micro-rings, incorporating bending and coupling losses is given in [5]. The analysis considers the effects of curvature-induced loss and coupling efficiency between waveguides. Authors in [6] investigated the impact of bending on power transmission losses in G652 and G657 optical fibers. They highlighted that G657 fibers exhibit lower bending losses due to their bend-insensitive design, making them more suitable for tight installations. The study provides insights into optimizing fiber selection for various applications to minimize signal degradation. In [7], the authors utilize a modified five-layer model. The study examines how bending radius and wavelength influence transmission loss, providing valuable insights for optimizing fiber optic performance in applications requiring tight bends. Their findings indicate that as the bending radius decreases, transmission loss increases exponentially, emphasizing the importance of adhering to minimum bend radius specifications to minimize signal attenuation.

Most of the work on calculating the bending loss was concentrated on the loss in the cladding area to determine the remaining transmitted power. In this paper, we derived a formula to calculate the losses in the outside area of the cladding region. This escaped power represents a transmission to the surrounding region required in some applications, such as wireless sensor networks, confined area communications, and underwater optical data collection.

The rest of the paper is organized as follows: In Section 1, we derived a closed formula that describes the fiber bend behavior and calculates the amount of escaped light power to the surrounding region as a function of bend radius. Our experimental work and how it aligns with the formula derived is shown in Section 2. In Section 3, we present an OLF Transmission Case Study, and finally, the conclusion and future work are given in Section 4.

2. Bending Loss

To implement an Optical Leaky Feeder (OLF), we devise a method of bending the fiber optics to allow part of the transmitted light to penetrate the cladding area to act as a transmission aperture (slot). These bends will act as an array of light-transmitting points. This will help in reducing the complexity of having multiple transmitters along the fiber. The effect of bending the optical fiber can be modeled as a power loss of the transmitted light signal. At bends, some of the rays escaped the optical fiber due to the incident angle being less than the critical angle. In [4,8], the loss due to bending in the cladding was derived. In [9,10], an experimental formula was investigated.

Here, we make use of the results obtained by [11,12,13] and study the light power escaped from the fiber bend to the outer surrounding media. Since we need to calculate the emitted light from an OLF, the overall effect can be modeled as a skewness in the light intensity distribution as shown in Figure 1.

In a straight optical fiber, the intensity distribution can be written as [14]:

I_{1} (r) = \frac{1}{w_{0} \sqrt{2 π}} e^{- \frac{r^{2}}{2 w_{0}^{2}}},

(1)

where w₀ is the Mode Field Diameter (MFD) of the fiber with a core radius of a and it can be written as [10]:

w_{0} = 2 a (0.65 + \frac{1.619}{V^{\frac{3}{2}}} + \frac{2.879}{V^{6}}),

(2)

where the Normalized Frequency V for step-indexed fiber is given by:

V = (\frac{2 π a}{λ}) \sqrt{\frac{n_{2}^{2} - n_{1}^{2}}{n_{0}^{2}}},

(3)

where n₀ is the Refractive Index (RI) of the surrounding medium, n₂ and n₁ are the RI of the core and cladding, respectively. Similarly for the graded index fiber:

V = (\frac{2 π a}{λ}) \sqrt{\frac{{n (r)}^{2} - n_{1}^{2}}{n_{0}^{2}}} .

(4)

Here, the graded index might have several shapes and is usually a function of r, λ is the wavelength of light propagating through the fiber, n₀ is the Refractive Index (RI) of the surrounding medium, n₁ are the RI of the cladding and

n (r)

is the RI profile in the core for the graded index fiber.

In a curved optical fiber, the intensity distribution can be modeled as a skewed function of the Gaussian distribution in (1). It can be written as [15,16,17]:

I_{2} (r, α) = \frac{2}{w_{0} \sqrt{2 π}} e^{- \frac{r^{2}}{2 w_{0}^{2}}} (1 + e r f (\frac{α r}{w_{0}})),

(5)

where

α

is the skewness parameter and can be determined following the steps in [18]. There will be micro bending loss as well as macro bending loss, such that, when the bending radius R decreases, the losses will increase. These losses practically vanish when the bending radius is larger than the critical radius Rc [19]. The relation between

α

and R can be written as:

α = \frac{α_{0}}{(R_{c} - R)} R < R_{c},

(6)

where

α_{0}

is a constant (Unitless) and R_c is given by [19]:

R_{c} ≅ 20 \frac{λ}{{(n_{2} - n_{1})}^{\frac{3}{2}}} {(2.748 - 0.996 \frac{λ}{λ_{c}})}^{- 3},

(7)

where λ is the wavelength of the propagated light and λ_c is the cutoff wavelength, which is given for step index by:

λ_{c} = (\frac{2 π a}{2.405}) \sqrt{\frac{n_{2}^{2} - n_{1}^{2}}{n_{0}^{2}}},

(8)

and graded index fiber is given by:

λ_{c} = (\frac{2 π a}{2.405 \sqrt{1 + 2 / β}}) \sqrt{\frac{n_{c}^{2} - n_{1}^{2}}{n_{0}^{2}}},

(9)

where β is a manufacturing constant which depends on the index profile n(r). Usually, β = 2 is a typical number used in industry and n_c is approximated to be the average of n(r). An empirical formula for n(r) is

n (r) = n_{1} \sqrt{2 ξ (1 - {(r / a)}^{2})},

(10)

where ξ is a constant and a is the core radius.

Figure 2 shows the light intensity profile for multiple bending radiuses from R = 100 µm to R = 1800 µm. The core radius a = 4.5 µm, the cladding radius b = 62.5 µm, n₀ = 1.0 (air), n₁ = 1.48, n₂ =1.5,

α_{0} = 32,780

, and λ = 1550 nm. The figure shows that as the bending radius decreases, the skewness shifts toward the outer region, resulting in increased leakage.

The total light power that entered the bend can be calculated as [14,20]:

P_{t o t a l} = 2 \int_{0}^{\infty} {[\frac{1}{w_{0} \sqrt{2 π}} e^{- \frac{r^{2}}{2 w_{0}^{2}}}]}^{2} d r .

(11)

The amount of optical power that escaped from the fiber to the external world can be calculated as:

P_{o u t} = \int_{R_{o u t}}^{\infty} {[\frac{2}{w_{0} \sqrt{2 π}} e^{- \frac{r^{2}}{2 w_{0}^{2}}} (1 + e r f (\frac{α r}{w_{0}}))]}^{2} d r .

(12)

And hence, the transmitted power efficiency for the OLF at any slot is given by:

η = \frac{P_{o u t}}{P_{t o t a l}} 100 % .

(13)

To calculate the integral in (12) we may use the following approximation:

\erf (x) = 1 - e r f c (x) ≅ 1 - \frac{e^{- x^{2}}}{x \sqrt{π}} .

(14)

Then, Equation (12) becomes:

P_{o u t} = \int_{R_{o u t}}^{\infty} {[\frac{2}{w_{0} \sqrt{2 π}} e^{- \frac{r^{2}}{2 w_{0}^{2}}} (2 + \frac{w_{0}^{2} e^{- \frac{{α^{2} r}^{2}}{w_{0}^{2}}}}{α r \sqrt{π}})]}^{2} d r .

(15)

And this will simplify to:

P_{o u t} = \int_{R_{o u t}}^{\infty} (\frac{2}{w_{0}^{2} π} e^{- \frac{r^{2}}{α^{2} w_{0}^{2}}} - \frac{4}{r w_{0}^{2} π^{3 / 2}} e^{- \frac{r^{2} (1 + α^{2})}{α^{2} w_{0}^{2}}} + \frac{2}{r^{2} w_{0}^{2} π^{2}} e^{- \frac{r^{2} (1 + 2 α^{2})}{α^{2} w_{0}^{2}}}) d r .

(16)

In seeking simplicity, let

M_{0} = \frac{2}{w_{0}^{2} π} M_{1} = \frac{2}{w_{0}^{2} π^{\frac{3}{2}}} and M_{2} = \frac{4}{w_{0}^{2} π^{2}},

(17)

K_{0} = \frac{1}{α^{2} w_{0}^{2}} K_{1} = \frac{(1 + α^{2})}{α^{2} w_{0}^{2}} and K_{2} = \frac{(1 + {2 α}^{2})}{α^{2} w_{0}^{2}} .

(18)

Then, we can rewrite (16) as:

P_{o u t} = \int_{R_{o u t}}^{\infty} (M_{0} e^{- K_{0} r^{2}} - \frac{M_{1}}{r} e^{- K_{1} r^{2}} + \frac{M_{2}}{r^{2}} e^{- K_{2} r^{2}}) d r .

(19)

The first integral term can be approximated by:

\int_{R_{o u t}}^{\infty} M_{0} e^{- K_{0} r^{2}} d r ≅ \frac{M_{0}}{2 K_{0}} (\frac{e^{- K_{0} R_{o u t}^{2}}}{R_{o u t}}) .

(20)

The second integral term is simplified as:

g (- K_{1} R_{o u t}^{2}) = \int_{R_{o u t}}^{\infty} \frac{M_{1}}{r} e^{- K_{1} r^{2}} d r = \frac{{M_{1} K}_{1}}{2} [\ln (K_{1} R_{o u t}^{2}) + \sum_{n = 1}^{\infty} {(- 1)}^{n} \frac{{(K_{1} R_{o u t}^{2})}^{n}}{n \cdot n!}] .

(21)

The last integral term can be approximated as:

\int_{R_{o u t}}^{\infty} \frac{M_{2}}{r^{2}} e^{- K_{2} r^{2}} d r ≅ M_{2} (\frac{2 e^{- K_{2} R_{o u t}^{2}}}{R_{o u t}} - \sqrt{{π K}_{2}}) .

(22)

Then, the emitted power is given by:

P_{o u t} ≅ \frac{M_{0}}{2 K_{0}} (\frac{e^{- K_{0} R_{o u t}^{2}}}{R_{o u t}}) - g (- K_{1} R_{o u t}^{2}) + M_{2} (\frac{2 e^{- K_{2} R_{o u t}^{2}}}{R_{o u t}} - \sqrt{{π K}_{2}}) .

(23)

This equation shows the behavior of the escaped light power as:

P_{o u t} ~ \frac{P_{o}}{R_{o u t}} e^{- β R_{o u t}^{2}} .

(24)

And the transmitted power efficiency can be approximated as:

η = \frac{η_{o}}{R_{o u t}} e^{- β R_{o u t}^{2}} \times 100 % .

(25)

This result shows the loss of transmitted power through emitting light outside of the cladding.

Using numerical calculations, Figure 3 shows the radiation efficiency for R = 1 mm to R = 37 mm (R_c = 20 mm). The used optical fiber has core radius a = 4.5 µm, the cladding radius b = 62.5 µm, n₀ = 1.0 (air), n₁ = 1.48, n₂ = 1.5,

α_{0} = 32,780

and λ = 1550 nm. The transmitted power efficiency (radiation efficiency) for R=1mm was found to be 25% and 0% for R > 20 mm.

Considering the power losses in the cladding region due to fiber bending in a single-mode optical fiber (curvature loss), Schermer in [10], Marcatili in [11,12], and Marcuse in [13] derived a formula for the loss in the cladding region that can be written as in [18] as:

L_{b} = 10 l o g (\frac{K_{b}}{\sqrt{R_{e f f}}} e^{- β R_{e f f}}) d B,

(26)

where R_eff is the effective bend radius, K_b and β are constants. This loss was calculated for the loss in the cladding region only at large bending radius, such that, negligible amount of light escaped the cladding area.

In this paper, we derived an approximate simple formula in Equation (24) that described the escaped light power from the optical fiber at the bending point. This power is considered as the transmitted power at that slot that forms a OLF configuration. In the following experiment we measure the escaped power and compare it with that found in Equation (24).

2.1. Experimental Results

The setup shown in Figure 4 is used to measure the light power that escaped from the optical fiber at different bend radii.

The measured output power at different bend radius is shown in Figure 5. The power launched into the fiber is 3 mW. A light power sensor placed 1mm from the fiber curvature is used to measure the light intensity in air. The fiber curvature is adjusted between R = 0.5 mm and R = 44 mm. The used optical fiber has core radius a = 4.5 µm, the cladding radius b = 62.5 µm, n₀ = 1.0 (air), n₁ = 1.48, n₂ = 1.5.

As shown in Figure 5, the relation between the bend radius and the transmitted power is very close to the derived one in Equation (24) and hence, we can assume that the approximations are valid.

2.2. Receiving Optical Fiber Slots

Using the same concept described above. The fiber bend can create a receiving terminal for the light coupled from the surroundings into the fiber. Some of the incident angles at the bend allow light to enter the fiber from the surrounding area. These angles satisfy Snell’s law, expressed as follows:

n_{0} \sin (θ_{0}) = n_{1} \sin (θ_{1}) = n_{2} \sin (θ_{2}),

(27)

where

θ_{0}

is the incident angle from air into cladding,

θ_{1}

is the incident angle from cladding into core and

θ_{2}

is the transmitted angle in the core that satisfies

θ_{2} \leq \frac{π}{2} - \sin^{- 1} (\frac{n_{2}}{n_{1}}) .

(28)

Therefore, the values of

θ_{0}

is given by:

θ_{0} \leq \sin^{- 1} (\frac{n_{2}}{n_{1}} \sin (θ_{2})) .

(29)

Therefore, some of the incident angles will satisfy Snell’s law, and light insertion into the optical fiber is possible.

In our experiment, n₀ = 1, n₁ = 1.48 and n₂ = 1.5. This will allow angles of less than 14.13° to penetrate the fiber. In the following section, we used the effect of bending of the optical fiber to generate transmitting points along the optical fiber. This creates an Optical Leaky Feeder (OLF) array transmitter.

3. OLF Transmission System Case Study

In this paper, we devised a system that uses OLF as an array of transmitting and receiving slots for free space and underwater communication systems. This technique will reduce the cost of implementing multiple transmitters at each location. The OLF transmission system includes a light transmitter/receiver, OLF, and a termination, as shown in Figure 6.

The transmitter has N slots and the light power at the input of the n-th slot is given by:

P_{i n}^{n} = P_{t} - L_{0} - [\sum_{i = 1}^{n - 1} (γ z + L_{b}^{i} + P_{o u t}^{i})],

(30)

where γ is the fiber attenuation in dB for a straight fiber per unit length, Pt is the transmitted light power, L0 is the loss in the first section of the OLF, z is the distance between slots,

L_{b}^{i}

is the core loss in the ith slot given in Equation (26) and

P_{o u t}^{i}

is the leaked light power from the ith slot given in Equation (23).

The radiated light power from the nth slot can be written as:

P_{o u t}^{n} = η_{n} (P_{i n}^{n} - L_{b}^{n}) .

(31)

Here, we add subscript for

η_{n}

to allow for different efficiencies to be used for each slot.

In order to control the transmitted power at a specific slot, we use a different bending radius, such that the closer the slot to the source, the larger the bend radius is chosen. The receiver has M slots that combine the received light into the detector.

This structure forms a MIMO system with received light signal written as:

y = H x + z,

(32)

where

y = [\begin{matrix} y_{1} \\ ⋮ \\ y_{M} \end{matrix}], x = [\begin{matrix} x_{1} \\ ⋮ \\ x_{N} \end{matrix}], z = [\begin{matrix} z_{1} \\ ⋮ \\ z_{M} \end{matrix}] and H = [\begin{matrix} h_{11} & \dots & h_{1 N} \\ ⋮ & ⋱ & ⋮ \\ h_{M 1} & \dots & h_{M N} \end{matrix}],

(33)

z is an AWGN and the transmitted signal x_i is given by:

x_{i} = \sqrt{P_{o u t}^{n}} s (t),

(34)

where s(t) is the message signal and the received signal y_j is given by:

y_{j} = \sum_{i = 1}^{N} h_{j i} \sqrt{P_{o u t}^{n}} s (t - τ_{i}) + z_{j},

(35)

where

τ_{i}

is the propagation delay in transmitting OLF. The received signal can be rewritten as:

y_{j} = \sum_{i = 1}^{N} h_{j i} \sqrt{η_{n} (P_{i n}^{n} - L_{b}^{n})} s (t - τ_{i}) + z_{j} .

(36)

The combined observed signal at the detector is given by:

y_{r} = \sum_{j = 1}^{M} (\sum_{i = 1}^{N} h_{j i} \sqrt{η_{n} (P_{i n}^{n} - L_{b}^{n})} s (t - τ_{i} - δ_{j}) + z_{j}),

(37)

where

δ_{j}

is the propagation delay in receiving OLF. We can design the receiving slots to be separated to compensate for the transmission delay in fixed scenarios, such as:

t_{0} = τ_{i} - δ_{j} \forall j, i .

(38)

This led to:

y_{r} = s (t - t_{0}) \sum_{j = 1}^{M} (\sum_{i = 1}^{N} h_{j i} \sqrt{η_{n} (P_{i n}^{n} - L_{b}^{n})} + z_{j}) .

(39)

Since a different coupling angle may be obtained at each receiving slot, the received signal at the receiver detector may be averaged. This effect can be modeled as a variation in the channel coefficient h_ji, such that the slots outside the acceptance cone (depending on the distance between transmitter and receiver) will have h_ji = 0. In this case, the OLF transmission system forms a MIMO system with diversity combiner at the receiver side [21]. The effect of limited acceptance cone can be written as:

y_{r} = s (t - t_{0}) \sum_{k = 1}^{N / I} \sum_{j = 1}^{M} (\sum_{i = 1}^{I} h_{j i} \sqrt{η_{n} (P_{i n}^{n} - L_{b}^{n})} + z_{j}) .

(40)

Here, N/I represents the total number of subgroups each with I slots. A simulation for the system is conducted using MATLAB (R2020b) with OOK modulation scheme, N = 100 transmitters and M = 50 receivers. We obtained the BER results shown in Figure 7. The effects of different types of noises and the photo-detection is assumed to contribute to the overall noise as an AWGN.

The simulation assumes a uniform slot distance of 0.5 m, distance between Tx OLF and 5 m for the Rx OLF. An acceptance cone with solid angle of 14.13° is assumed. This investigated configuration results of five transmitting slots that are within the acceptance cone.

4. Conclusions

This paper derived a closed formula to determine the transmitted power from an optical fiber bend slot. The slot is used as a transmitter to form an OLF array transmitter. This can be considered as a simple solution for many applications including wireless sensor networks, confined area communications, and underwater optical data collection. In this paper, we only simulate the BER performance for the OLF to show the visibility of using the OLF in a simple MIMO communication system that is designed for confined areas. In the future, we plan to extend our work to other applications.

The derived formula provided a good fit for experimental data, as shown in Figure 5. The most noticeable point in this work is that the derived expression of the leaked power is a function of R2, while in Marcuse [4] it was a function of R. Marcuse calculated the leaked power in the cladding, while in our work, we derived an expression for the leaked power in the surrounding environment. Moreover, in this work we found that losses increase exponentially with decreasing bend radius, with significant losses observed for radii smaller than the mode field diameter. The study demonstrates that by accurately modeling and controlling bending loss, optical leaky feeders can be effectively implemented for special applications. These feeders can support high-speed communication in confined or challenging environments, such as in underground tunnels and in hospitals, where RF-based systems face limitations. Precise modeling also enables more efficient system designs, reducing the trial-and-error approach often required in optical system development.

Limitations and Future Work

While the closed-form expression showed strong alignment with experimental data, the study was limited to specific fiber types and wavelengths. Future work should extend the model’s validation to diverse fiber structures and broader wavelength ranges. Additionally, further research on integrating optical amplifiers within the leaky feeder system could help mitigate overall attenuation and extend operational range. Also, multimode fiber should be considered, since we believe it will introduce a mode interference that is hard to control.

Author Contributions

Conceptualization and methodology, H.F. and J.S.R.; software, J.S.R.; validation, D.I.A., I.M., A.K.A. and X.F.; writing—original draft preparation, H.F. and J.S.R.; writing—review and editing, H.F. and J.S.R.; funding acquisition, H.F. and X.F. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author.

Conflicts of Interest

Author Ahmad K. Atieh was employed by the company Optiwave Systems Inc. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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Figure 1. Light intensity profile before and inside fiber bending.

Figure 2. Light intensity profile inside bent fiber for R = 100 µm to R = 1800 µm in 10 steps.

Figure 3. Efficiency (×100%) vs. Bend Radius (mm).

Figure 4. Experiment Setup.

Figure 5. Measured Output Power (dBm) vs. Bend Radius(mm), and a Plot of Equation (24) as Dotted Line.

Figure 6. OLF as MIMO Transmission System.

Figure 7. BER vs. SNR (dB) for OLF MIMO System.

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Farahneh, H.; Rahhal, J.S.; Abualnadi, D.I.; Mansour, I.; Atieh, A.K.; Fernando, X. An Experimental Study of Radiated Energy from an Optical Fiber and the Potential for an Optical MIMO System. Appl. Sci. 2025, 15, 2916. https://doi.org/10.3390/app15062916

AMA Style

Farahneh H, Rahhal JS, Abualnadi DI, Mansour I, Atieh AK, Fernando X. An Experimental Study of Radiated Energy from an Optical Fiber and the Potential for an Optical MIMO System. Applied Sciences. 2025; 15(6):2916. https://doi.org/10.3390/app15062916

Chicago/Turabian Style

Farahneh, Hasan, Jamal S. Rahhal, Dia I. Abualnadi, Ibrahim Mansour, Ahmad K. Atieh, and Xavier Fernando. 2025. "An Experimental Study of Radiated Energy from an Optical Fiber and the Potential for an Optical MIMO System" Applied Sciences 15, no. 6: 2916. https://doi.org/10.3390/app15062916

APA Style

Farahneh, H., Rahhal, J. S., Abualnadi, D. I., Mansour, I., Atieh, A. K., & Fernando, X. (2025). An Experimental Study of Radiated Energy from an Optical Fiber and the Potential for an Optical MIMO System. Applied Sciences, 15(6), 2916. https://doi.org/10.3390/app15062916

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An Experimental Study of Radiated Energy from an Optical Fiber and the Potential for an Optical MIMO System

Abstract

1. Introduction

2. Bending Loss

2.1. Experimental Results

2.2. Receiving Optical Fiber Slots

3. OLF Transmission System Case Study

4. Conclusions

Limitations and Future Work

Author Contributions

Funding

Institutional Review Board Statement

Informed Consent Statement

Data Availability Statement

Conflicts of Interest

References

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