Reflection Coefficient Curves Research Articles

Acoustic Wave Reflection in Water Affects Underwater Wireless Sensor Networks.

The phenomenon of acoustic wave reflection off fluid-solid surfaces is the focus of this research. This research aims to measure the effect of material physical qualities on oblique incidence acoustic attenuation across a large frequency range. To construct the extensive comparison shown in the supporting documentation, reflection coefficient curves were generated by carefully adjusting the porousness and permeability of the poroelastic solid. The next stage in determining its acoustic response is to determine the pseudo-Brewster angle shift and the reflection coefficient minimum dip for the previously indicated attenuation permutations. This circumstance is made possible by modeling and studying the reflection and absorption of acoustic plane waves encountering half-space and two-layer surfaces. For this purpose, both viscous and thermal losses are taken into account. According to the research findings, the propagation medium has a significant impact on the form of the curve that represents the reflection coefficient, whereas the effects of permeability, porosity, and driving frequency are relatively less significant to the pseudo-Brewster angle and curve minima, respectively. This research additionally found that as permeability and porosity increase, the pseudo-Brewster angle shifts to the left (proportionally to porosity increase) until it reaches a limiting value of 73.4 degrees, and that the reflection coefficient curves for each level of porosity exhibit a greater angular dependence, with an overall decrease in magnitude at all incident angles. These findings are given within the framework of the investigation (in proportion to the increase in porosity). The study concluded that when permeability declined, the angular dependence of frequency-dependent attenuation reduced, resulting in iso-porous curves. The study also discovered that the matrix porosity largely affected the angular dependency of the viscous losses in the range of 1.4 × 10-14 m2 permeability.

Design and Optimization of a High-Gain Filtering Antenna Based on Parasitic Pixel Layer

A novel high-gain filtering antenna based on the parasitic pixel layer is designed and optimized in this paper. Initially, a circular patch surrounded by a shorted concentric annular ring one is proposed as the radiation source, such a design is able to realize an upper radiation null. Afterward, a parasitic pixel layer is placed upon the radiation source with an air gap. Another radiation null at the lower band is then obtained by optimizing the connection status between adjacent pixel elements based on the internal multi-port method. Besides that, the parasitic pixel layer can enhance the realized broadside gain. Finally, a high-gain filtering antenna with a bandpass response is obtained. The antenna is validated by a full-wave simulation study followed by the experimental verification. Measured results indicate that the antenna can operate from 4.7 to 5.4 GHz with an average gain of 9.6 dBi and two radiation nulls at the lower and upper band edges of the reflection coefficient curve.

Bandwidth enhanced deltoid leaf fractal antenna for 5.8 GHz WLAN applications

A wideband deltoid leaf fractal antenna is proposed for 5.8 GHz commonly used in industrial scientific and medical (ISM) and wireless local area networks (WLAN) applications. A microstrip patch antennas is designed with leaf shape radiating element. Using a leaf shape, it is possible to increase the perimeter of a design and thus reduce the overall dimensions of the antenna. A circular ring slot is made on the leaf shaped radiator, in a way that a circular disc is loaded at centre. Triangular fractal slots are made inside the circular disc to make it miniaturized. A partial ground is maintained with slot at centre. The antenna is fed by micro-strip feed. The locality and measurements of the fractal slots are varied to make the antenna radiate at 5.8 GHz with wider bandwidth (BW) of (2.26 GHz). The complete size of the antenna is 40 mm 3 × 40 mm 3 × 1.6 mm 3 . The step-by-step implementation of the antenna and the effects of its dimensions are compared and presented using the reflection coefficient curve. The measured reflections coefficient |S11|<-10 dB maintained the operational band from (5.36 GHz - 7.62 GHz), with gain 4.2 dBi. The proposed antenna is planned and simulated using high frequency structure simulator (HFSS). The simulated and measured comparison showed good agreement, the designed antenna is suitable for 5.8 GHz WLAN applications with wider bandwidth requirements.

Electromagnetic Transparent Antenna With Slot-Loaded Patch Dipoles in Dual-Band Array

A novel electromagnetic transparent low-band (LB) antenna is given in this article, with a good impedance matching in the band of 0.69–0.96 GHz (VSWR < 1.5). The key feature lies in its great patch dipoles with low-scattering properties. The transparent performance is achieved by loading slots on the dipoles, instead of inserting chokes. Dagger-like slot plays an important role in both impedance matching improvement and scattering suppression. An extra resonance point can be introduced to the reflection coefficient curve in the operating band, so the impedance matching problems can be alleviated. Besides, a dual-band shared-aperture array was designed and fabricated for validation. Both simulated and measured results have proved that the LB antenna has satisfactory impedance characteristics within the operating band and achieves an electromagnetic transparency in the band of 1.7–2.4 GHz.

Flexible ultra-wideband cartoon-shaped antenna based on a composite with customizable dielectric properties

This paper presents a flexible ultra-wideband (UWB) and deformation-insensitive antenna. The proposed antenna was based on a Mickey-shaped patch, a coplanar waveguide fed, and a flexible composite substrate, which was built by a polydimethylsiloxane (PDMS) matrix and short-diameter powders of polytetrafluoroethylene (PTFE), with customizable dielectric properties. Furthermore, PTFE, magnesium oxide, titanium oxide, and zirconia powders were used as four fillers with different weight ratios to modify and control the dielectric properties of the dielectric substrate (the relative permittivity: 2.75–3.07, the dielectric loss tangent: 0.02–0.05), and then we characterized PDMS-based composites through Young’s modulus, Raman spectra, and surface topography. Finally, we fabricated and measured the proposed antenna with the dimensions of 50 mm × 60 mm × 0.5 mm. The measured reflection coefficient curves showed an operating frequency band from 1.9 GHz to 43.5 GHz, and the measured fractional bandwidth reached 183.3%. It was proved that the antenna had stable performance when it was bent or stretched. Moreover, the antenna was simulated and measured in the proximity of the human body, which verified the antenna robustness and safety for use on a human. The proposed UWB and deformation-insensitive antenna is a promising candidate for wearable applications and wireless communication.

Investigation of electronic and optical properties of PbxSn1-xO2 for optoelectronic applications: A TB-mBJ DFT approach

A comprehensive study of electronic and optical properties of PbxSn1-xO2 (x = 0.125, 0.25 and 0.375) have been performed utilizing PBE-GGA + TB-mBJ scheme employing WIEN2K package under DFT formalism. The lattice constant parameters obtained for PbxSn1-xO2 are observed to be invariant with rutile SnO2. The DoS (Density of States) profile of PbxSn1-xO2 states a dominant impact of partial states of Pb along the conduction band. A red shift of conduction band edge has been observed with increasing Pb incorporation in PbxSn1-xO2 supercells. The contribution due to partial states of O is supreme as compared to Pb along the valence band, as also encountered in SnO2. The nature of bandstructure is in parity with DoS profile. With increased incorporation of Pb atoms in PbxSn1-xO2 supercells, a significant lowering of conduction band minimum occurs thereby resulting in reduced band gap. The nature of reduction of optical band gap values is in parity with the electronic band structure. The optical parameter characteristic curves undergo redshift due to increased Pb incorporation in PbxSn1-xO2 supercells. Distinct peak values in absorption characteristic curve claims the material to have direct band gap. Higher value of static refractive index causes dispersion in the material. The real (imaginary) part of dielectric constant is consistent with the refractive index (extinction coefficient) characteristic curves. The reflection coefficient curve indicates lossy nature of the material. The reflection coefficient curve contradicts the loss coefficient characteristic curve. Hence, the consequences of this investigation claim the competency of PbxSn1-xO2 material for optoelectronic applications.

Predicting the Reflection Coefficient of a Viscoelastic Coating Containing a Cylindrical Cavity Based on an Artificial Neural Network Model

A cavity viscoelastic structure has a good sound absorption performance and is often used as a reflective baffle or sound absorption cover in underwater acoustic structures. The acoustic performance field has become a key research direction worldwide. Because of the time-consuming shortcomings of the traditional numerical analysis method and the high cost of the experimental method for measuring the reflection coefficient to evaluate the acoustic performance of coatings, this innovative study predicted the reflection coefficient of a viscoelastic coating containing a cylindrical cavity based on an artificial neural network (ANN). First, the mapping relationship between the input characteristics and reflection coefficient was analysed. When the elastic modulus and loss factor value were smaller, the characteristics of the reflection coefficient curve were more complicated. These key parameters affected the acoustic performance of the viscoelastic coating. Second, a dataset of the acoustic performance of the viscoelastic coating containing a cylindrical cavity was generated based on the finite element method (FEM), which avoided a large number of repeated experiments. The minmax normalization method was used to preprocess the input characteristics of the viscoelastic coating, and the reflection coefficient was used as the dataset label. The grid search method was used to fine-tune the ANN parameters, and the prediction error was studied based on a 10-fold cross-validation. Finally, the error distributions were analysed. The average root means square error (RMSE) and the mean absolute percentage error (MAPE) predicted by the improved ANN model were 0.298% and 1.711%, respectively, and the Pearson correlation coefficient (PCC) was 0.995, indicating that the improved ANN model accurately predicted the acoustic performance of the viscoelastic coating containing a cylindrical cavity. In practical engineering applications, by expanding the database of the material range, cavity size and backing of the coating, the reflection coefficient of more sound-absorbing layers was evaluated, which is useful for efficiently predicting the acoustic performance of coatings in a specific frequency range and has great application value.

Plasmon Resonances of Graphene-Dielectric-Metal Structures Calculated by the Method of Recurrence Relations

Graphene supports surface plasmons in the terahertz range, and compared with noble-metal plasmons, they show an extreme level of field confinement and relatively long propagation distances, with the advantage of being highly tunable via electrostatic field. Nevertheless, its interaction with light is normally rather weak. To obtain a more powerful capability of excite plasmons, a combination of graphene and artificial structures (metamaterials) present a powerful tunability for enhancing light-matter interaction. These features make graphene metamaterials a promising candidate for plasmonics and surface plasmon resonance for biological sensors. In this work, we study the plasmon spectra in a finite number of graphene layers on a metallic-dielectric substrate surrounded by materials with different dielectric constants. It is shown that using standard electromagnetic boundary conditions and solving the recurrence relation (a suitable alternative to transfer matrix method) for the coefficients of the electric potential between graphene layers, an explicit effective dielectric function of the metamaterial can be obtained giving the plasmon dispersion relations. It is found that the metal-dielectric-layered graphene structure supports both high-energy optical plasmon oscillations and out-of-phase low-energy acoustic charge density excitations. Experimentally, the Kretschmann configuration can be used to excite the surface plasmon resonances. It is based on the observation of a sharp minimum in the reflection coefficient versus angle (or wavelength) curve.

Continuous and elastically consistent viscoelastic reflection and transmission coefficient curves for plane inhomogeneousPandSwaves

SUMMARYFor inhomogeneous plane waves in dissipative media, correctly selecting the vertical slowness (q) is the key requirement to obtain physically acceptable reflection/transmission (R/T) coefficients (e.g. both continuous curves as a function of incidence angle, and consistency with the elastic coefficients at very low attenuation). Based on the fundamental branch-cut theory, the continuity criterion ensures the continuity of the R/T coefficient curves. The elastic consistence is obtained due to the definition of the mixed principal values and the consistent assumptions of time dependence of the harmonic plane wave, the Z-direction of the spatial coordinate system and the particle motion (polarization) vectors. The elastic consistence of R/T coefficients is checked by both elastic models with zero dissipation factor (1/Q) and the equal-Q model in which the Q values of the incident wave and the R/T waves are non-zero but equal for the P and S waves on both sides of the interface. In particular, the previously reported 180° phase difference between the viscoelastic coefficients with arbitrarily small attenuation but the same ratio of Q across the interface and the corresponding elastic coefficients is circumvented by introducing the mixed principal value. The continuity criterion is implemented directly in the complex vertical slowness squared (q2) plane in which the branch-cut is defined. Furthermore, the loci of q2 and several ‘critical angles’ defined for anelastic waves are clearly investigated and clarified. The loci of q2 are expressed as a function of the incidence angle and the incident wave inhomogeneity parameter D. The plots of wave inhomogeneity parameter (D and/or attenuation angle γ) versus incidence angle are calculated from the slowness vectors. The resultant D values, especially their equality for all vertically propagating R/T waves, are examined using the complex Snell's law to provide extra support to the correctness of the slowness vectors and thus of the R/T coefficients. It is worth noting that phase angle of the R/T waves from an inhomogeneous incident wave may exhibit rapid changes at vertical incidence because near-vertical reflection is still the dominant application of the exploration seismic method. To the best of our knowledge, this research is the first time it has been possible to obtain continuous and elastically consistent viscoelastic R/T coefficients.

Nanocomposite Graphene based Tunable Absorber for Combating Electromagnetic Pollution

Background: Advancement in wireless communication technology has raised today’s living standards but has consequently led to the problems of electromagnetic (EM) air pollution as well as spectrum congestion particularly in radio frequency band. To overcome the traffic congestion problem in lower bands, terahertz frequency bands are explored but EM pollution still persists as a global issue, which can be addressed by a tunable microwave absorber. At THz frequencies, 2-D nanostructured graphene has been observed to be less lossy than using other materials and further finds its most interesting applications on account of the plasmonic mode supported by graphene resulting in extreme device miniaturization. At micro and mm-waves, graphene is resistive, hence it can be electronically controlled, ensuring its suitability for the design of tunable microwave absorber. Objective: Designing of a frequency reconfigurable or frequency tunable absorber is the prime objective of the current work. Two-dimensional graphene absorber has been proposed here having inherent bandgap tunability property, which means the electromagnetic properties of graphene can be controlled via varying external bias potential. Methods: The numerical modelling of graphene microwave absorber utilizing bulk graphene backed by glass and perfect electric conductor layer is reported in this paper. Finite element Method (FEM) based high frequency structure simulator (HFSS) platform is used to simulate the graphene absorber model. The whole structure is placed into a rectangular waveguide with two ports for absorber excitation. Results: The variation of electromagnetic properties of graphene absorber is achieved by changing bias potential and further the absorption tunability for the designed absorber is investigated in the range from 2 GHz to 18 GHz. From reflection coefficient curves, it is authenticated that -72.6 dB reflection coefficient dip is obtained at 14 GHz for 5 volt bias potential, which shifts to higher side of frequency as the potential changes from 5 volts to 25 volts. Conclusion: The results show that by increasing bias potential, absorption coefficient shifts to higher frequency and proves to be a tunable wideband absorber whose resonant frequency can be changed from one value to another without changing thickness or material properties of absorber, thus it can effectively incorporate with antenna substrate or surface of radar.

Reflection of oblique incident acoustic waves at various fluid–solid interface for varying material properties

In this paper, the reflection of acoustic waves obliquely incident onto various fluid–solid interfaces is investigated. This study aims to measure the influence of solid material properties on the acoustic attenuation magnitude, for oblique incidence at varying frequencies. A detailed comparison is documented by plotting the reflection coefficient curve for each case, while meticulously varying the porosity & permeability of the poroelastic solid. Further attention is focused on identifying the shift in the pseudo-Brewster angle and the dip in the reflection coefficient minima for the aforementioned permutations in attenuation to measure its acoustic response. To enable this, the reflection and absorption of acoustic plane waves incident upon half-space and two-layer interfaces are modelled (by including viscous and thermal losses) and studied. Based on the findings, the study draws significant conclusions on the strong influence of the propagating media on the shape of the reflection coefficient curve and the relative influence of the permeability, porosity, and driving frequency on the pseudo-Brewster angle and the curve minima.

Reflection of Hydrogen Isotopes and Helium Atoms from the Surface of the First Wall of the ITER Tokamak

The reflection coefficients were calculated for the scattering of hydrogen isotopes and helium atoms from the surface of amorphous beryllium, carbon, and tungsten targets, which are of interest in the physics of thermonuclear plasma. The results demonstrate good agreement with the available experimental data. The isotope effect in the reflection of particles from the wall was analyzed. For the reflection of He atoms, a similarity in reflection coefficient versus Lindhard parameter curves was observed.

A stable miniaturised AMC loaded flexible monopole antenna for ingestible applications

This paper proposes an ultra-miniaturised, flexible 5.8 GHz antenna to give better performance for an ingestible wireless capsule endoscopy system. The use of an artificial magnetic conductor (AMC) unit cell in this design helps in enhancing the gain, improving the efficiency and reducing the size at resonance. This novel AMC-based layer is modelled as a radiator, and is excited by a complementary strip feed. The proposed design is printed on a flexible polyimide material of size 4.6 × 7.6 × 0.15 mm, with dielectric constant 3.5 and loss tangent 0.008. The antenna has an omni-directional radiation pattern with gain 1.64 dBi. The size is reduced drastically by bending the structure to fit inside a standard-sized ingestible capsule of 26 × 11 mm. The performance metrics of the antenna after placing inside the wireless ingestible capsule are presented with the help of an analysis of the reflection coefficient curves, radiation pattern, specific absorption rate (SAR) and field distributions. In addition, different positions and orientations of the antenna and different bending conditions are used, and these cases are solved using our AMC-based unit cell radiator. We carry out simulations using High Frequency Structure Simulator (HFSS) and measurements are made by immersing the fabricated antenna in minced meat. The results of this novel structure are compared with those of other ingestible antennas proposed in the literature. The proposed design has a SAR value of 0.82505 W/kg at around 5.8 GHz over 1 g of tissue, thereby redirecting the radiation away from the human body. This conformal AMC structure achieved better miniaturisation while maintaining the antenna resonance and SAR within permissible limits.

P.436 Cognitive function in alcohol dependent patients after six months of out-patient treatment

This paper proposes an ultra-miniaturised, flexible 5.8 GHz antenna to give better performance for an ingestible wireless capsule endoscopy system. The use of an artificial magnetic conductor (AMC) unit cell in this design helps in enhancing the gain, improving the efficiency and reducing the size at resonance. This novel AMC-based layer is modelled as a radiator, and is excited by a complementary strip feed. The proposed design is printed on a flexible polyimide material of size 4.6 × 7.6 × 0.15 mm, with dielectric constant 3.5 and loss tangent 0.008. The antenna has an omni-directional radiation pattern with gain 1.64 dBi. The size is reduced drastically by bending the structure to fit inside a standard-sized ingestible capsule of 26 × 11 mm. The performance metrics of the antenna after placing inside the wireless ingestible capsule are presented with the help of an analysis of the reflection coefficient curves, radiation pattern, specific absorption rate (SAR) and field distributions. In addition, different positions and orientations of the antenna and different bending conditions are used, and these cases are solved using our AMC-based unit cell radiator. We carry out simulations using High Frequency Structure Simulator (HFSS) and measurements are made by immersing the fabricated antenna in minced meat. The results of this novel structure are compared with those of other ingestible antennas proposed in the literature. The proposed design has a SAR value of 0.82505 W/kg at around 5.8 GHz over 1 g of tissue, thereby redirecting the radiation away from the human body. This conformal AMC structure achieved better miniaturisation while maintaining the antenna resonance and SAR within permissible limits.

Design and Characterization of Periodically Conductive Woven Fabric

Abstract In this paper, a novel kind of electromagnetic (EM) functional textiles is proposed, which show high-pass characteristics as they interact with EM waves. The periodically conductive woven fabric was designed, fabricated, and measured. Specifically, by means of unit cell model building and EM simulation, the theoretical S21 (transmission coefficient) and S11 (reflection coefficient) curves were obtained. A concrete sample was fabricated through weaving process, and its transmission characteristics were measured in the microwave anechoic chamber. The measured and simulated results were highly consistent, demonstrating the validity of design process. Compared with the aluminum foil paper sample, the S21 values of fabricated sample were a little smaller, and the reason could be attributed to yarn crimp and surface roughness. The EM characteristics of fabricated sample under two different polarization modes were slightly different, which was due to the beating-up tension of weaving process. The work could offer new research ideas, and the related products have potential advantages over rigid plates on the account of textile characteristics.

Numerical simulation of borehole Stoneley wave reflection by a fracture based on variable grid spacing method

In this paper, the finite difference method is used to model the Stoneley wave reflection by a horizontal fracture in a borehole. The fracture shape is described by some finite difference grids. Therefore, the fracture aperture can be varied in the radial direction, thus extending previous researches on the assumption that the fracture aperture is constant throughout the fracture. Finite difference grids can also be used to describe a fracture which extends a finite distance in the radial direction. In addition, the finite difference algorithm can deal with the problem of inhomogeneous formation. Therefore, it allows the variation of formation elasticity in the model. Fine grids are needed to describe the small fracture aperture, and variable grid spacing is employed by finite difference method to improve computational efficiency. The Stoneley wave propagation is simulated by the variable grid spacing finite difference method in several models with variable fracture aperture, finite extension fracture and models with heterogeneous formation. The variable grid spacing finite difference method is validated through a comparison with real axis integration method and the analytical method. We get some conclusions by simulating and investigating effects of the variation of fracture aperture, the fracture of finite extension and inhomogeneity of formation on the Stoneley wave reflection. Although the fracture aperture changes along the fracture extension direction, the reflection coefficient of Stoneley wave is mainly controlled by the fracture aperture near the borehole. The Stoneley wave in the fracture is reflected back into the borehole, by the tip of finite extension fracture, which results in some notches in the reflection coefficient curve. If the Stoneley wave propagates from the formation with small elastic modulus to the formation with large elastic modulus, the reflection coefficient of Stoneley wave will be larger than that of homogeneous model with small elastic modulus. And if Stoneley wave propagates from the formation with large elastic modulus to the formation with small elastic modulus, the reflection coefficient of Stoneley wave will be smaller that of homogeneous model with large elastic modulus. These results provide some basis for the use of Stoneley wave to detect the fracture properties in formation.

Design and Analysis of Complimentary Split Ring Resonator Backed Microstrip Transmission Line Using Equivalent Circuit Model

This article presents a compact, low-profile Band-Stop Filter (BSF) designed using Complimentary Split Ring Resonator (CSRR). An equivalent circuit model is also presented along with the simplified mathematical approach to extract the parameters of the circuit model. This paper also presents the effect of variation in the dimensions of split rings on characteristics of BSF. The proposed BSF has a compact size of 27 × 20 mm2 designed an FR-4 substrate with dielectric constant ( $${{\varepsilon }_{r}}$$ ) 4.3. The filter provides complete suppression of the band at 2.4 GHz. The design and circuit analysis of this metamaterial based filter is presented in terms of reflection coefficient, transmission coefficient and impedance curve.

A modified approach for Elastic Impedance Inversion due to the variation in value of K

Elastic impedance inversion is the latest development in the field of hydrocarbon exploration and production. The present research focuses on the improvement of the use of elastic impedance inversion, easing exploration of hydrocarbons. The seismic velocities change with variation in geological constraints. Constant K, which is S-wave to P-wave ratio of the nth layer and n+1 layer across the interface, it must be changed accordingly. This research focuses on testing the effects of K as a constant in the elastic impedance equation. As using the same value of K for all types of formations can give rise to severe errors in the interpretation of data. The importance of the value of K for particular Amplitude Variation with Offset AVO type (I-IV) is studied using different Elastic Impedance Equations. The Reflection Coefficient (RC) curves for each AVO class are generated using Zoeppritz approximation and Elastic Impedance equations. The comparison of RC curves shows significant variations at far offsets in each AVO type using the Constant value of K. When K Calculated is used, AVO type I and Type II shows a good match at near, mid and far offsets. Type III does not change due to the changing value of K. Type IV gives good agreement at near and intermediate offsets. This variation in curves, with the change in the value of K, indicates that it is a significant factor of interpretation using elastic impedance. The application of findings on well logs has given a satisfactory confirmation of the present results. This research can be helpful to resolve severe errors in the interpretation due to the constant value of K.

Novel method to measure unloaded quality factor of resonant cavities at room temperature

We demonstrated a novel method to measure the unloaded quality factor (Q factor) of high-Q resonant cavities. This method was used to obtain data with low errors and calculate the unloaded Q factor. This procedure was more reliable than traditional methods. The data required for the method were near the resonant frequency, not at the half-power points of the reflection coefficient curve or Smith chart. We applied the new method to measure a resonant cavity with an unloaded Q factor of ~ 100,000, obtaining good agreement between the measured and theoretical results.

Effects of sand-shale anisotropy on amplitude variation with angle (AVA) modelling: The Sawan gas field (Pakistan) as a key case-study for South Asia's sedimentary basins

Amplitude variation with angle (AVA) is a technique widely used in the characterisation of hydrocarbon reservoirs and assumes the Earth’s crust to be an isotropic medium. Yet, anisotropy is ubiquitous in stratigraphic sequences and has first-order effects on seismic AVA responses when investigating subsurface prospects. This work analyses the effects of anisotropic strata on AVA responses using the Lower Goru Formation, middle Indus basin (Pakistan) as a case study. In the study area, shale intervals are interbedded with reservoir sands of the Sawan gas field. Shales in this field form laminae or are dispersed within reservoir sands, making the Lower Goru Formation an example of a vertically transversely isotropic (VTI) medium. In this work, we calculate the effective (saturated) mechanical properties of the Lower Goru Formation based on rock physics templates; the Backus (1962) average typically designed for layered media, combined with the empirical relations of Brown and Korringa (1975) and Wood (1955). The input data used in our rock physics modelling is based on detailed petrophysical analyses of well data. Using the saturated effective mechanical properties of the Lower Goru Formation, we generate angle-dependent reflection coefficient curves (and seismic AVA responses) based on exact and approximate solutions, for both isotropic and anisotropic reservoir scenarios. Our results suggest that the effects of lithological anisotropy are more pronounced in places with thick shale beds within reservoir sands. Conversely, angle-dependent reflection curves, and seismic AVA responses based on isotropic or anisotropic cases, give similar solutions in the presence of thin shale beds. As a corollary of this work, we present a Bayesian inversion method for the estimation of porosity in VTI media.