LTE Frequency Bands Research Articles

Multi-Band Coupled-Fed Antenna for 4G LTE, Sub-6G, and WLAN Frequency Bands in Various Electronic Devices

Multi-Band Coupled-Fed Antenna for 4G LTE, Sub-6G, and WLAN Frequency Bands in Various Electronic Devices

Analysis on The Effect of Channel Bandwidth Occupying in LTE Frequency Band on Throughput

The maximum channel capacity of a 4G LTE network will be directly correlated to the channel bandwidth that occupies a certain radio frequency on that network. The number of Resource Blocks (RB), subcarriers, and Resource Elements (RE) as channel resources available to serve users concurrently will depend on the bandwidth channel sizes. Mobile service providers in Indonesia provide scalable channel bandwidth LTE 4G networks on a variety of frequency bands, including adjacent and non-adjacent bands. In this study, it was examined how to channel bandwidth, which changes at 10MHz, 15MHz, and 20MHz, affects throughput to give user equipment the best possible performance (UE). This study makes use of actual measurement data from installed and active eNodeB or cells obtained via the drive test approach. According to the test, each channel's maximum throughput varies, however, there is no linear relationship found between channel bandwidth expansion and throughput. The 20MHz channel bandwidth, which is located in the 2300MHz frequency band, has a maximum throughput value of 64666.80 kbps.

Beam Shaping of Base Station Antenna Array by Using MMPTE

In this paper, a beam shaping scheme is presented for the optimal design of base station antenna array. The antenna array consists of four linearly arranged dual-band dual-polarized antenna elements, and it is designed to cover the LTE frequency band (2.3-2.69 GHz) and 5G frequency band (3.3-3.6 GHz). The shaped beams with possible maximum gain, suppressed sidelobe level smaller than -16 dB, front-to-back ratio larger than 18dB, and filled-up null point larger than -23 dB are accomplished through two steps by using the unconstrained methods of maximum power transmission efficiency (MMPET) and constrained MMPTE, respectively. In the proposed beam shaping scheme, all the realistic factors of the antenna array have been taken into account, such as the difference of element radiation patterns, complexity and tolerance of the element structure and spacing.

Comparison of radio propagation models in five LTE coverage cells in Riobamba

This article performs a comparative analysis of the power intensity levels measured with the Network Cell Info Lite application and the performance of the different propagation models: Log-Normal, Okumura Hata, COST 231, Walfish Bertoni, and SUI in the 4G LTE Frequency Band. The study was conducted in five LTE coverage cells located in the southern area of the city of Riobamba. The model that best fits each cell was chosen by means of absolute error analysis, thus obtaining an empirical correction factor for the proposed models. For the analysis of the absolute error, three measurement campaigns were carried out with 50 samples where the mean value was obtained. After applying the aforementioned models, the Log-Normal model yielded the most favorable results, being the one that achieved the best adaptation in Riobamba, since the power levels vary in the range (-80; -106) dBm at a coverage area not exceeding 200m.

Design and Investigation of Dual-Band 2 × 2 Elements MIMO Antenna-Diplexer Based on Half-Mode SIW

In this article, a compact dual-band, 2-elements antenna-diplexer is investigated and extended to a 2&#x00D7;2 multi-input and multi-output (MIMO) antenna. The proposed design employs half-mode Substrate Integrated Waveguide (HMSIW) technology, which reduces the antenna footprint by 50%. To enhance the bandwidth, a rectangular slot is engraved at the center of each HMSIW cavity. The slot splits the dominant mode of the HM cavity into two odd- and even-half TE110 modes in a proximity, which leads to enhancement in the bandwidth by 50%. The antenna resonates around 3.4 GHz with a fractional bandwidth of 5% and around 4.3 GHz with a bandwidth of 4.7%, when corresponding ports are excited, respectively. Both the lower and upper frequency bands can be tuned individually, by simply altering the dimensions of each HMSIW cavity. This can be achieved in a common antenna, without employing filters, which satisfies the antenna-diplexer function. The isolation levels between any two radiating elements are obtained below -23 dB for the proposed MIMO antenna, and it occupies overall size of 1.0&#x03BB;<i>_g</i> &#x00D7; 0.8&#x03BB;<i>_g</i>. The peak gain of the antenna is obtained 5.35 dBi in the lower frequency band and 6.75 dBi in the upper frequency band while radiation efficiency is better than 80% in both frequency bands. The MIMO antenna properties have been evaluated and all found satisfactory. The envelope correlation coefficient (ECC) is obtained less than 0.13, DG around 9.9 dBi, and mean effective gain (MEG) around -3.05 dB. The 2&#x00D7;2 MIMO antenna is prototyped and experimentally verified. The measured results are closely following the simulation counterparts. The proposed 2&#x00D7;2 MIMO antenna is an appropriate alternative for LTE frequency bands in 5G wireless communication.

Rain Effect on 4G LTE In-Car Electromagnetic Propagation Analyzed Through MDT Radio Data Measurement Reported by Mobile Phones

Mobile networks’ evolution is strictly related to connected cars evolution, making in-car propagation modeling and analysis key enablers in the forthcoming telecommunication competition scenario. The recent availability of mobile device power measurements enriched by GPS position, the so-called 3GPP minimization of drive test (MDT) feature, nowadays, empowers new approaches to propagation studies targeting mobile service and quality improvements. The novelty of the research presented in this article is the use of a huge quantity of MDT geolocated radio measurements in a connected state (more than 370 million during the three-day MDT campaign) along 187 km of Italian A22 Motorway, part of the planned Munich-Bologna EU cross-border corridors for connected and automated mobility (CAM). In particular, MDT measurements of LTE received signal received power (RSRP) are compared between rain and dry road situations, showing how wet environments reshape electromagnetic propagation, even for LTE frequency bands (below 3 GHz) that have line-of-sight propagation marginally influenced by rain. Explanations of measured effects and simulations are presented. The rain effect on cellular propagation should be carefully considered in the perspective of connected car evolution, specifically considering new worldwide available 5G bands, more affected by rain situations, and autonomous driving scenarios.

Metamaterial Integrated Folded Dipole Antenna with Low SAR for 4G, 5G and NB-IoT Applications

The fast growth of wireless technology for mobile communication devices requires broad bandwidth, high data rate facilities and compact device size. The solution to the next generation user equipment is high data rate 4G/5G technologies. In this research, wideband antenna design was analyzed and evaluated for 4G, 5G and NB-IoT applications. CST microwave studio was used for simulations and investigations of the performance parameters. The antenna was designed as a folded dipole with a tunable bandwidth and resonates for 5G NR n78, NR-IoT bands B1, B2, and B25, and eleven TDD LTE frequency bands with a bandwidth percentage and minimum scattering loss of 69.02% and −42 dB respectively. Additionally, the designed antenna is small (35 × 48 × 1.62 mm3) and planar in structure and can be easily integrated with radio equipment. The antenna design was also investigated for SAR minimization and gain enhancement using metamaterial integration. For all operating frequency bands, the antenna design results in a considerable gain improvement. The metamaterial was shown to be an excellent absorber of radiation, particularly in high frequency regions. This research also included a SAR examination with and without metamaterial integration. SAR values were found to be significantly reduced throughout all operating bands. The results were validated by fabricating the design prototype on FR-4 substrate for 4G, 5G and IoT bands. The antenna will be possibly used for communication in high data rate applications.

A Flexible Digitally Controlled Oscillator Structure to Reconfigure the Frequency Band in Multi-band RF AD-PLL System

Reconfigurable architectures are more prominent in modern-day multi-band radio systems. This work has been conceptualized for a flexible 8-bit digitally controlled oscillator (DCO) design to suit reconfigurable RF all-digital phase-locked loop applications. To efficiently utilize the area, power consumption and attend to several operating frequencies, an optimal design of LC-tank based DCO topology with both L and C components contributing to the coarse and fine-tuning of the DCO’s frequency of oscillation has been proposed. The design has been carried out in the Cadence Spectre RF tool with UMC180 nm technology. The proposed 8-bit DCO exhibits wide bandwidth, generating 240 oscillating frequencies in the LTE frequency band and occupies less area of 70 × 18 µm. The frequency of oscillation varies from 491.5 MHz to 3.392 GHz designed for an 8-bit digital control word with a tuning range percentage of 149%. The maximum phase noise obtained is −103.57 dBc/Hz @ 10 MHz offset causing a figure of merit (FOM) of −144.167 dBc/Hz. The total power consumed by the DCO ranges from 1.05 to 9.5 mW approximately.

The use of edge cut on microstrip antenna patch with the modified partial ground plane for bandwidth enhancement

This research proposes the use of edge cut on the antenna patch with a modified partial ground plane to overcome the inherent characteristic of the microstrip antenna, which is narrowband. The antenna has to cover all of the LTE frequency bands, which is from 0.824 – 2.4 GHz. FR4 epoxy with a dielectric constant of 4.4 and a thickness of 1.67 mm is used as a substrate for the antenna. The proposed antenna is simulated by an EM Simulator. The simulated results show that the return loss of -18.82 dB and the VSWR of 1.25. These parameters confirms that the antenna is well-matched along with the LTE bands. This wideband antenna has a directional radiation pattern with a maximum gain of 4.65 dB.

Cross Polarized 2x2 LTE MIMO System for Automotive Shark Fin Application

In this research we propose two orthogonally placed FR4 printed planar monopole antenna elements for use in the automobile roof top shark fin antenna for LTE MIMO applications. The discussed MIMO antenna system is designed to cover the worldwide LTE frequency band from 698MHz to 2700MHz. The goal of this research is to achieve satisfactory MIMO performance across the whole band while staying within physical constraints of the shark fin style antenna. The target reflection coefficient (S11) of each element is -6dB. Because of physical constraints of the automotive shark fin design antenna MIMO decorrelation is achieved by cross polarization and small distance separation. Correlation better than -12dB is targeted and achieved in higher bands, while in lower frequency bands antennas would not benefit from MIMO performance. Numerical simulation of the MIMO antenna system is performed using FEKO in order to verify the design parameters. Simulation findings are confirmed by manufacturing antennas and testing in the lab.

Printed dual‐band base station antenna for GSM/DCS/PCS/UMTS and LTE applications with dual polarization

SummaryA new design of the dual‐band and dual‐polarized base station antennas for supporting the mobile communication systems operating at the GSM/DCS/PCS/UMTS and LTE frequency bands is presented. A wide input impedance matching bandwidth is achieved due to a trident‐shaped feeding technique. Two printed dipoles, which are located perpendicularly to each other and fed by stepped‐microstrip lines, establish the proposed antenna. In addition, by locating a low‐profile cavity‐backed structure, as a metal reflector under the antenna, bidirectional radiations of the dipoles are switched to unidirectional radiations with an increase in the gain of the antenna. Measurement results indicate that the proposed antenna is suitable for base station applications at the operating frequencies of 800/900/1800/1900/2300 MHz. The isolation is better than 20 dB, and peak gains of 10.08 and 9.96 dBi are attained at port‐1 and port‐2, respectively. Furthermore, the HPBWs of the antenna in H‐plane is more than 61° for each port. The overall dimension of the antenna is 168 × 168 mm2, which is mounted upon a 222 × 222 mm2 cavity‐backed structure with a depth of 42 mm.

Design of a Multi-Band Microstrip Textile Patch Antenna for LTE and 5G Services with the CRO-SL Ensemble

A textile multi-band antenna for LTE and 5G communication services, composed by a rectangular microstrip patch, two concentric annular slots and a U-Shaped slot, is considered in this paper. In the ground plane, three sleeved meanders have been introduced to modify the surface current distribution, leading to a bandwidth improvement. The U-Shaped slot, the dual circular slots, and the meanders shape have been optimized by means of the Coral Reefs Optimization with Substrate Layer algorithm (CRO-SL). This population-based meta-heuristic approach is a kind of ensemble algorithm for optimization (multi-method), in which different search operators are considered within the algorithm. We show that the CRO-SL is able to obtain a robust multi-band textile antenna, including LTE and 5G frequency bands. For the optimization process, the CRO-SL is guided by means of a fitness function obtained after the antenna simulation by a specific simulation software for electromagnetic analysis in the high frequency range.

5G Is Going Live in Country After Country [Mobile Radio

As 5G is switched on in one country after another, the significance of this technology for all sectors of society will become increasingly apparent. The June 2019 edition of "Ericsson Mobility Report" [1] presents a glimpse of the impressive progress in the mobile telecommunication market, now on the verge of deploying 5G. The report forecasts 1.9 billion 5G subscriptions by the end of 2024. That's up from 1.5 billion forecast in the November 2018 edition, an increase of almost 27%. Other forecasts have also increased notably due to the rapid 5G uptake. It is expected that 5G coverage will reach 45% of the world's population by the end of 2024. This could surge to 65%, as spectrum -sharing technology enables 5G deployment on LTE frequency bands.

A Proposed Model of Metamaterial Complementary Split- Ring Resonator to Reduce Microstrip Array Antenna Dimension

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POLARIZED DIVERSITY COMPACT PLANAR MIMO ANTENNA FOR WIRELESS ACCESS POINT APPLICATIONS

In this paper, a wideband polarization diversity multi-input multioutput (MIMO) antenna system is proposed. The structure of the proposed antenna consists of four wideband coplanar waveguide (CPW)-fed monopole antennas with a common ground plane and radiated element. The simulated and measured -10 dB impedance bandwidth is 20% (2.25-2.75 GHz), which covers WiFi (2.4 GHz) and LTE (2.6GHz) frequency bands. The MIMO antenna system is applied to both an indoor and outdoor wireless access point (WAP) at the covered frequency bands. Due to the common structure of elements in the proposed MIMO antenna, an acceptable mutual coupling between the antennas ports is critical. Hence, a new parasitic element structure is presented to improve mutual coupling between the antenna ports. Acceptable values for the coupling coefficient (< -14 dB) are achieved by adding the parasitic element. The presented antenna system provides a nearly omnidirectional radiation pattern with an orthogonal mode of linear polarization. The results show a polarization diversity gain of 10 dB and an envelope correlation coefficient of less than 0.2. Moreover, each antenna port possesses peak gains of 5.33-6.97 dBi and efficiencies of 51.5-57%. A comparison between the simulation results and experimental measurements reveals good agreement between the two, confirming the validity of the proposed design.

A Tunable Single-Feed Triple-Band LTE Antenna With Harmonic Suppression

This paper presents a single-feed planar inverted-F antenna (PIFA) that operates at three resonant frequencies within the LTE frequency range which would result in the enhancement of the antenna bandwidth and the increase of the data-rate speed. The antenna is designed to satisfy the requirements of carrier aggregation systems (intraband non-contagious type) cell-phone applications. The three resonant frequencies are independently tunable within the low-band (0.7-1 GHz), mid-band (1.6-2.1 GHz), and highband (2.1-2.7 GHz), respectively, using varactor diodes as tuning devices. Each varactor diode represents a variable capacitor controlled by biasing dc voltage. A parallel LC harmonic-trap filter is built inside the antenna to suppress the harmonics generated by the low-band resonance, which enhances the tuning capabilities at the high-band. The antenna has a size of 375 mm2, which is considered to be a low-profile design and placed on a 100 × 66 × 3.154 mm 3 RO4003C (e r = 3.55) printed circuit board. The measured antenna radiation patterns in each band are nearly isotropic as expected from the PIFA and the measured antenna radiation efficiency is 25-80% within the entire LTE frequency bands.

High-Efficiency Crossed-Loop 4G LTE Antenna for All Display Metal-Rimmed Smartphones

A symmetrically crossed-loop antenna featuring very high radiation efficiency across the entire LTE frequency bands for metal-rimmed smartphones with only 2 mm ground clearance is proposed, analyzed, and verified. The employment of even and odd modes is utilized to achieve wide bandwidth across 698–960 MHz (low-frequency spectrum), 1710–2170 MHz (middle-frequency spectrum), and 2300–2690 MHz (high-frequency spectrum). Empirical analysis confirms the crossed-loop topology results in a 180° phase shift of the electric current distribution on the ground plane, resulting in enhancement of the radiation resistance. As a result, the devised LTE antenna exhibits more than 48% to 75% total system efficiency across the entire band of interest, which is the highest efficiency reported in literature for metal-rimmed smartphones with extremely small ground clearance.

Dual Band Metamaterial Antenna For LTE/Bluetooth/WiMAX System

A compact metamaterial inspired antenna operate at LTE, Bluetooth and WiMAX frequency band is introduced in this paper. For the lower band, the design utilizes an outer square metallic strip forcing the patch to radiate as an equivalent magnetic-current loop. For the upper band, another magnetic current loop is created by adding metamaterial structure near the feed line on the patch. The metamaterial inspired antenna dimension of 42 × 32 mm2 compatible to wireless devices. Finite integration technique based CST Microwave Studio simulator has been used to design and numerical investigation as well as lumped circuit model of the metamaterial antenna is explained with proper mathematical derivation. The achieved measured dual band operation of the conventional antenna are sequentially, 0.561~0.578 GHz, 2.346~2.906 GHz, and 2.91~3.49 GHz, whereas the metamaterial inspired antenna shows dual-band operation from 0.60~0.64 GHz, 2.67~3.40 GHz and 3.61~3.67 GHz, respectively. Therefore, the metamaterial antenna is applicable for LTE and WiMAX applications. Besides, the measured metamaterial antenna gains of 0.15~3.81 dBi and 3.47~3.75 dBi, respectively for the frequency band of 2.67~3.40 GHz and 3.61~3.67 GHz.

FREQUENCY RECONFIGURABLE PATCH ANTENNA FOR 4G LTE APPLICATIONS

A compact printed multi-band frequency reconfigurable patch antenna for 4G LTE applications is presented in this paper (50 x 60 x 1.6 mm3). The antenna consists of W-shaped and Inverted-U shaped patch lines connected in a Tree-shape on the front side of the antenna. The back-side of the antenna contains a 90°-tilted T-shaped strip connected with an Inverted-L shaped strip which is shorted with a patch on the front side for increasing the electrical length to cover lower frequency bands. Frequency reconfigurability is achieved by inserting three switches i.e., PIN diodes. The most critical part of this work is the designing of RLC-based DC line circuits for providing the DC biasing to the PIN diodes used as switches and inserting them at optimum locations. This antenna is reconfigurable among eight different 4G LTE frequency bands including 0.9 GHz, 1.4 GHz, 1.5 GHz, 1.6 GHz, 1.7 GHz, 1.8 GHz, 2.6 GHz, 3.5 GHz and WLAN band 2.5 GHz. The antenna exhibits different radiation patterns having a different direction of peak gain at different frequencies and for different switching combinations. The antenna is simulated with CST, and a prototype is fabricated to compare the measured and simulated results with good accuracy.

LTE-U and WiFi carrier aggregation

Latest scientific research in the wireless communications standards include an approach development that will allow WiFi users to hop over to licenced LTE frequency bands. The idea is when unlicenced LTE bands become overcrowded these frequencies to be utilized for data transfer. A cognitive radio technology scans for available spectrum, that is free in order to allow WiFi user to `jump`in the licenced free LTE frequencies each milisecond. After such WiFi user identifies an available alocation in the licenced band, connection is established and data transfer is initiated. Test on WiFi connectivity reach up to 160% increase in performance than the rest, as latency periods are reduced to zero. It is expected every real network to double its capacity with the utilization of the WiFi spectrum.