Inter-band Carrier Aggregation Research Articles

Analysis on the Impact of Implementing Inter-band Carrier Aggregation (CA) on the 5G-NR Networks

Currently, cellular technology is advancing into the 5G era, which can support data speeds up to 10 Gbps on the uplink side and 20 Gbps on the downlink side. This study aims to plan a 5G NR network by implementing the inter-band carrier aggregation (CA) method. CA is one of the techniques used to achieve high data speeds and to combine two or more radio frequency bands. The primary cell uses band n40 at 2300 MHz with a 40 MHz bandwidth, while the secondary cell uses band n78 at 3500 MHz with a 100 MHz bandwidth. The area that we used for this network design is Agung Podomoro Land (APL) Tower Central Park area in West Jakarta. The propagation model used Urban Macro. Testing process is carried out by comparing the results between using CA and not using CA on the SSRSRP, SS-SINR, and data rate parameters. Simulation results show an average increase in each parameter after the inter-band carrier aggregation method is applied. The SS-RSRP parameter increased by 0.05% with a value of -82.02dBm, the SS-SINR parameter increased by 0.77% with a value of 15.71dB, and the data rate parameter significantly increased by 241.33% with a value of 803.66 Mbps. This proves that implementing the carrier aggregation method can improve the quality and capacity of the network, particularly the data rate, by maximizing the use of the bandwidth and resource block produced by the combination of component carriers.

The Evaluation of the Throughput Performance of an LTE-Advanced Urban Area Network with the Inter-Band Non-Contiguous Carrier Aggregation Method

Data obtained from the drive-test in the urban area (a case study of Siliwangi Stadium, Bandung) revealed that the low throughput occurred on the downlink, which was 3.56 Mbps. On the uplink, it was 20.7 Mbps. Additionally, based on the Operating Support System (OSS) data, the site had high resource block usage (80% of PRB usage). It revealed the high traffic volume in the area, which resulted in poor throughput values received by users. The area is one of the potential market areas in the city of Bandung, which is indicated by housing, military area command education and training regiment, schools, hotels, markets, and stadiums. Based on the Site Database (SDB), it was known that the site has not yet implemented the carrier aggregation method. This study evaluated throughput using the Inter-Band Non-Contiguous Carrier Aggregation method by comparing three scenarios: Non-CA, CA Non-Repeater, and CA Repeater. Based on the results of the non-CA simulation, the downlink throughput increased by 23,582 Mbps, and the uplink throughput by 20.098 Mbps. Meanwhile, in the non-repeater CA simulation, the downlink throughput increased by 44.56% to 34.091 Mbps, and the uplink throughput increased by 39.22% to 27.980 Mbps. Furthermore, the CA Repeater simulation increased downlink throughput by 63.70% to 38.603 Mbps and uplink throughput by 45.06% to 29.154 Mbps.

Comparative Analysis of TDD Frame Structure Technology LTE-Advanced (A Case Study in Cibitung Area Indonesia)

Based on the results of the drive-test, it showed that 72.22% of the Gramapuri Tamansari Cibitung area had downlink throughput quality below the standard of Key Performance Indicator (KPI) parameter, which was less than 8 Mbps. In addition, based on the Operation and Support System (OSS) data, in this area, the value of Physical Resource Block (PRB) utilization reached 83.93%; thus, an additional capacity from the downlink was needed. This study aims to compare Time Division Duplexing (TDD) frame structure and Inter-Band Carrier Aggregation FDD-TDD method in the Cibitung area, with band 3 FDD 1800 MHz and band 40 TDD 2300 MHz by simulation using Atoll 3.3 software. The parameters measured are downlink throughput, uplink throughput, RSRP, SINR, and connected user. The simulation results showed improving downlink throughput by 63%, uplink throughput by 65%, and connected users by 4%.

Dual-Band Power Amplifier Design at 28/38 GHz for 5G New Radio Applications

This paper presents the design of a dual-band power amplifier (PA) featuring similar performance at 28 GHz and 38 GHz. In the new radio (NR) of the fifth generation (5G) communication system, the inter-band carrier aggregation technique is commonly adopted for data rate enhancement. In such configuration, operation at both bands of the 5G frequency range 2 (FR2) spectrum is often necessary. The stacked-FET topology was adopted for mitigation of the gain roll-off with frequency to achieve similar performance at both frequency bands. Implemented in the commercial 0.15-μm gallium arsenide (GaAs) pseudomorphic high electron mobility transistor (pHEMT) technology, the PA delivered a small signal gain of 18.5/18 dB, an output power at saturation (P_sat) of 28.5/28.2 dBm, and a peak power-added efficiency (PAE) of 39%/36% at 28/38 GHz, respectively. The measurement results have demonstrated great potential of the proposed PA for 5G NR applications.

Performance Analysis of 5G Stand Alone Inter-band Carrier Aggregation

Today, high data rate is the prior requirement to support services and applications. It is definitely a challenge for the 5G New Radio (NR) in providing high data rates, in order to support use cases, especially enhanced Mobile Broadband (eMBB). The objective of this research is to design a 5G network which has greater data rates employing carrier aggregation techniques. Carrier Aggregation (CA) is a way which is able to improve data rates by aggregate component carriers, hence, it can make a wider bandwidth. There are three modes of CA scenario that can be used: intra-band contiguous CA, intra-band non-contiguous CA, and inter-band noncontiguous CA. In this research, the 5G network planning with carrier aggregation on inter-band employing bandwidth 40 MHz at frequency 2300 MHz and bandwidth 100 MHz at frequency 3500 MHz was simulated in Mentum Planet software. The simulation implemented at Marunda Center Industrial Area in Bekasi used downlink outdoor-to-indoor (O2I) with Line of Sight (LOS) scenario. The parameters analyzed in this research employed three main parameters: SS-RSRP, SS-SINR and data rate, which resulted CA SS-RSRP increased by 0.14%, SSSINR increased by 4.48%, and peak data rate increased up to 1412.26 Mbps from 312.872 Mbps

Proposed Operation Scenarios for Inter-Band Carrier Aggregation and Spatial Multiplexing Multiple Antenna System in LTE-Advanced Network

Proposed Operation Scenarios for Inter-Band Carrier Aggregation and Spatial Multiplexing Multiple Antenna System in LTE-Advanced Network

Wideband 23.5–29.5-GHz Phased Arrays for Multistandard 5G Applications and Carrier Aggregation

This article presents a 23.5–29.5-GHz $8\times 8$ phased array for wideband multistandard applications. The array is based on wideband high-performance $2\times 2$ transmit/receive (TRX) quad-beamformer chips with 6 bit of phase control and 8 bit of gain control. The antenna is designed using a stacked-patch structure combined with a two-stage impedance matching network to enhance its bandwidth. The $8\times 8$ phased array achieves an effective isotropic radiated power (EIRP) of 54.8 dBm at P1dB with a 3-dB bandwidth of 23.5–30.5 GHz and can scan to ±60° in the azimuth plane and +/40° in the elevation plane with excellent patterns with a single-point calibration at 27 GHz. Measured error vector magnitude (EVM) for a 64-QAM 200 and 800-Mbaud waveforms result in a system EVM of 5% (−26 dB) in the TX mode at an average EIRP of 46–47 dBm at 24.5–29.5 GHz. Also, the wideband array is capable of 16-QAM 24-Gb/s links with an EVM <16% over all scan angles. An interband carrier aggregation (CA) system is also demonstrated with the wideband array using 200-Mbaud 64-QAM waveforms with 25- and 29-GHz carriers. The phased-array phase and amplitude settings are chosen such that the 25- and 29-GHz waveforms are radiating simultaneously at the same angle with low scan loss, resulting in an efficient system. Also, the out-of-band third-order intermodulation products generated by the power amplifier on each element are filtered out by the antenna. CA measurements with up to 50° scan angles are demonstrated with low EVM. To the best of our knowledge, this is the first demonstration of CA in millimeter-wave fifth-generation (5G) systems.

Throughput Performance Evaluation of LTE-Advanced with Inter-band Carrier Aggregation

The increasing number of mobile smartphone users requires additional spectrum to maintain cellular quality of service. The 800 MHz band is a good candidate to achieve this goal. It can be used as standalone spectrum or aggregated with other licensed bands to increase the available bandwidth. This paper compares through physical layer simulation the downlink throughput versus distance performance of LTE-Advanced in two different bands. We consider a high frequency band at 2.6 GHz and the 800 MHz to model bands 7 and 20 of inter-band carrier aggregation CA_7-20 respectively. The link level simulation is performed for single antenna system at three different urban locations. The channel is modelled using an enhanced 3D ITU-R channel model combined with measured 3D radiation patterns for the base station and user equipment antennas. The BER versus SNR results show that the 800 MHz band enjoys a gain of up to 1 dB as a result of higher Ricean K-factors. Moreover, for the assumed simulation parameters, at distances beyond 400 m the throughput of the 800 MHz band is significantly higher than the 2.6 GHz band. At a distance of 750 m, the throughput for the 800 MHz band is 4.5 times greater than the 2.6 GHz band. These benefits are shown to relate to the lower path loss values observed in the 800 MHz band.

Increasing LTE-Advanced Network Capacity Using The Inter-band Carrier Aggregation (Downlink Side) Method

According to the identification of the Operating Support System (OSS) by the Smartfren cellular operator in the Central Bandung area, six sites are found to have high traffic capacity with the physical resource block (PRb) percentage of 82.6 %. The use of PRb &gt; 80 % is included in the warning indicator 2 based on the operator’s standards. It is also strengthened by the condition of the existing sites with the average Reference Signal Receive Power (RSRP) of -103.3 dBm, Signal to Interference Noise Ratio (SINR) of 6.28 dB, and throughput of 27.78 Mbps, thus resulting in non-optimal network performance in the area. Therefore, in this study, the inter-band Carrier Aggregation (CA) was applied by combining the 40 Time Division Duplex (TDD) band (2300 MHz) and band 5 Frequency Division Duplex (FDD) (850 MHz). One of the advantages of applying this method is that it can increase the user network capacity by maximizing the resources owned by the operator. The predetermined scenario taking into account the initial network condition indicated a decrease in the PRb percentage by 44.50 % and an increase in the average RSRP value by 12.8 dBm, SINR by 5.14 dB, and throughput by 34.59 Mbps.

A Sub-6-GHz 5G New Radio RF Transceiver Supporting EN-DC With 3.15-Gb/s DL and 1.27-Gb/s UL in 14-nm FinFET CMOS

The world’s first single-chip RF transceiver to support 5G sub-6-GHz new radio (NR) and long-term evolution (LTE) E-UTRA New Radio-Dual Connectivity (EN-DC) in 14-nm FinFET CMOS technology is presented. The single-chip transceiver integrates identical primary and diversity receivers (RXs) with seven pipelines for supporting four inter-band carrier aggregation (CA) with three 4 $\times $ 4 MIMO, two independent transmitter (TX) chains, eight frequency synthesizers for RX and TX, and on-chip digitally controlled crystal oscillator (DCXO) to reduce the phase noise and bill of material (BOM) cost. The receiver features 12 single-ended low-noise amplifiers (LNAs) with wideband characteristics. With the help of the proposed pipeline structure and frequency-band switchable transformer, the die size can be reduced despite covering the whole frequency range from 2G to sub-6-GHz 5G NR. It achieves the noise figure (NF) from 6.5 to 9.3 dB, +3-dBm out-of-band (OOB) IIP3, more than +70-dBm OOB IIP2 after calibration. For the transmitter, low RX-band noise and harmonic suppression technique are applied to support surface acoustic wave (SAW)-less architecture, and the bandwidth control of the baseband filter is implemented for the digital pre-distortion (DPD) operation of 100-MHz BW in NR transmit data. The measured error vector magnitudes (EVMs) in 4G and 5G bands of n79 are −39.5 dB at +4-dBm output power and −33.9 dB at +3.06-dBm output power, respectively, and the measured RX-band noise of 2G is −163 dBc at 20-MHz offset. The RX consumes 18 mW at LTE 1-CA mode and the TX consumes 350 mW at n79.

Energy-Efficient Virtual Radio Access Networks for Multi-Operators Cooperative Cellular Networks

5G networks will be characterized by massive densification of base stations (BSs). To minimize the network power consumption due to the increased BS deployment, we leverage emerging paradigms to propose BS energy-saving strategies applicable to 5G networks. We explore the potentials of virtualized radio access and core networks to enable spectrum sharing among mobile network operators (MNOs) by harnessing inter-band non-contiguous carrier aggregation. We propose the sleep-mode with efficient beamformers and spectrum-sharing (SEBS) strategy, which minimizes BS power consumption of cooperative MNOs. The licensed bandwidth of each MNO is partitioned into private and shared bands to provision active BSs with sufficient spectrum resources for serving all UEs. Moreover, an optimization problem is formulated to obtain the optimal intra- and inter-RAN beamforming vectors for efficient BS transmission power and improved user signal reception. Numerical simulations show that the proposed strategies yield significant reductions of total power consumption as compared to other schemes. We present different bandwidth sharing ratio formulations to motivate the cooperation among MNOs by the spectrum-user support trading. We also show that the trading does not always yield a higher spectral efficiency in the cooperative cellular network.

A Reconfigurable 28-/37-GHz MMSE-Adaptive Hybrid-Beamforming Receiver for Carrier Aggregation and Multi-Standard MIMO Communication

This paper presents a multi-standard fully connected hybrid beamforming (FC-HBF) receiver that can be reconfigured between two fully connected two-stream multi-input-multi-output (MIMO) modes at 28- or 37-GHz band, and an inter-band carrier-aggregation (CA) mode enabling concurrent single-stream operation at 28 and 37 GHz. A new image-reject (IR) heterodyne beamforming architecture is introduced that facilitates easy reconfiguration. Concurrent dual-band operation of the beamformer front end is achieved by using an inherently wideband Cartesian-combining-based RF-domain complex-weighting architecture, which is implemented using coupled-resonator-based dual-band gain stages, and current-mode dual-band active combiners. The downconversion stage comprises a cascade of complex-quadrature mixing stages that combines Cartesian complex-weighting operation with image rejection. A new quadrature error detection and calibration scheme is also introduced to improve the image rejection of the proposed architecture. A minimum mean-square error (MMSE) beam adaptation technique, introduced for the first time in an RF or hybrid beamformer, breaks the need for individual access to the beamformer inputs needed in a traditional least-mean-square (LMS) scheme and allows both main lobe and null adaptation. A 28-/37-GHz hybrid beamforming receiver with four antenna inputs and two baseband output streams is designed in 65-nm CMOS that demonstrates the above features. In each antenna path, the receiver achieves 33-dB (26.5 dB) peak conversion gain, 2.75-GHz (3.75 GHz) RF bandwidth, and 5.7-dB (8.5 dB) NF at 28 GHz (37 GHz). The entire receiver consumes 310 mW and occupies 2.2 mm2 core area. Extensive characterization results for single-element and several multi-element scenarios are presented including concurrent dual-band receiving (>35-dB image rejection), null-steering (>25-dB peak to null for two elements), and multi-element CA (~50-dB inter-carrier interference rejection).

A Wideband Inductorless LNA for Inter-band and Intra-band Carrier Aggregation in LTE-Advanced and 5G

A Wideband Inductorless LNA for Inter-band and Intra-band Carrier Aggregation in LTE-Advanced and 5G

Energy Efficient Power Allocation for Carrier Aggregation in Heterogeneous Networks: Partial Feedback and Circuit Power Consumption

The energy-efficient power allocation for carrier aggregation (CA) in heterogeneous networks (HetNets) is studied in this paper. We assume that multiple component carriers belong to HetNets and, thus, inter-band CA is considered, where both full and partial feedback scenarios are investigated. For the latter, we consider quantized channel state information at the transmitter and the corresponding power allocation policies are derived. Next, we derive energy-efficient optimal power allocation policies by assuming circuit power consumption for the transmitter that account for the multiple radio frequency (RF) chains required to support massive inter-band CA. The resulting algorithms are then used in order to investigate the relation between optimal energy efficiency (EE) and design parameters such as the number of frequency bands, antennas and feedback allocation through controlling the quantized information. A greedy optimization algorithm is also introduced to jointly optimize the aforementioned parameters. By carrying out simulations, it is observed that the achievable EE gains for massive CA in HetNets is further limited by either the number of feedback bits or the increase in RF circuits power consumption.

System Level Study of LTE-Advanced Multiple Antenna System with Inter-Band Carrier Aggregation

Spatial Multiplexing (SM) multiple antenna systems and Carrier Aggregation (CA) are techniques introduced in Long Term Evolution- Advanced (LTE−Advanced) to support high data rates by increasing the number of transmission paths and the available bandwidth respectively. Therefore, in this study we evaluate the performance of LTE-Advanced physical downlink shared channel for single and SM multiple antenna systems in two different frequency bands. The radio channel is modelled using an enhanced Three-Dimensional (3D) international telecommunication union-radio communication sector channel model integrated with base station and user mobile 3D antenna patterns. Except the total received power, similar channel statistics are observed for both frequency bands. The study is performed considering 1x1, 2x2, 4x4 antenna systems in a macro-cell urban environment at Component Carries (CC) of 2600 MHz and 800 MHz to model bands 7 and 20 of CA_7-20 respectively. The performance is evaluated in terms of throughput and SM gain for many base stations and user positions considering various modulation and coding schemes. We used the computationally efficient received bit information rate algorithm to compute the throughput as a function of channel structure and signal to noise ratio. As expected higher throughput is observed for the 800 MHz band over the 2600 MHz band. This is due to the higher total received power of the 800 MHz band. The novel SM gain results show that the SM gain depends on the operating band and it’s less than the number of spatial links. Moreover, the efficiency of inter-band CA in increasing the data rates is a function cell radius and the number of spatial streams.

Investigations of Component Carrier Selection Algorithms in Long Term Evolution-Advanced

&lt;p&gt;Given that the demand for real-time multimedia contents that require significantly high data rate are getting of high popularity, a new mobile cellular technology known as Long term Evolution-Advanced (LTE-A) was standardized. The LTE-A is envisaged to support high peak data rate by aggregating more than one Component Carriers (CCs) of the same or different frequency bandwidths. Since the inter-band non-contiguous carrier aggregation is likely to be used due to the current frequency allocation, this paper provides a performance study of a number of CC selection algorithms for use in the inter-band non-contiguous downlink LTE-A. It should be noted that CC selection is of paramount importance in the LTE-A operating in backward compatible mode as the LTE-A contains a mixture of the legacy Long Term Evolution (LTE) users that support packets (re)transmission on a single CC and the LTE-A users that utilize more than one CCs for packets (re)transmission. Simulation results demonstrated the efficacy of the Channel-Throughput Aware (CTA) algorithm for maximizing the system capacity without compromising the required Quality of Service of real-time video users.&lt;/p&gt;

Carrier Aggregation of Three OFDM Signals Using a Single Oscillator and I/Q Modulator

In this paper, a novel method is presented, which makes carrier aggregation (CA) using a single local oscillator and an in-phase/quadrature (I/Q) modulator, possible. Three component carriers with orthogonal frequency division multiplexing are generated at 2.2, 2.5, and 2.9 GHz to show the feasibility of the method for the worst case scenario that is the interband CA. A special procedure to compensate the I/Q imbalances specific to this method is explained as well. Moreover, according to Nyquist criterion, the signal should have a sampling rate at least twice the signal highest frequency. In this method, the sampling rate of the digital-to-analog converter is significantly reduced, because, the baseband signal is distributed over negative and positive frequencies. In addition, the demodulation process of these frequency-aggregated signals using a three-phase demodulator is explained and experimental results are presented.

High Performance Receiver Design for RX Carrier Aggregation

Carrier aggregation is one of the key features to increase the data rate given a scarce bandwidth spectrum. This paper describes the design of a high performance receiver suitable for carrier aggregation in LTE-Advanced and future 5 G standards. The proposed architecture is versatile to support legacy mode (single carrier), inter-band carrier aggregation, and intra-band carrier aggregation. Performance with carrier-aggregation support is as good as legacy receivers. Contradicting requirements of high linearity and the low noise is satisfied with the single-gm receiver architecture in addition to supporting carrier aggregation. The proposed cascode-shutoff low-noise trans-conductance amplifier (LNTA) achieves 57.1 dB voltage gain, 1.76 dB NF (noise figure) , and - 6 . 7 dBm IIP3 (Third-order intercept point) with the power consumption of 21.3 mW in the intra-band carrier aggregation scenario. With legacy mode, the same receiver signal path achieves 56.6 dB voltage gain, 1.33 dB NF, and - 6 . 2 dBm IIP3 with a low power consumption of 7.4 mW.

Enhanced coverage through relay assisted carrier aggregation for cellular networks

Carrier aggregation (CA) is an important feature of next generation cellular networks to meet the growing demand for wireless broadband services from fast-growing mobile users. This also facilitates the efficient use of fragmented spectrum among users of varying data rates. However, this does bring in a number of new implementation challenges, among which energy efficiency along with ensuring coverage and capacity fairness for users becomes the fundamental challenge for such systems. This paper initially analyses the outage capacity of such systems for both intra- and inter-band CA. Then, relaying is proposed as an energy efficient technique for enhancing the capacity and coverage of such systems. In this context, the ergodic rate of a typical user is analysed for both single- and multi-flow relay assisted CA systems. Different band deployment configurations are also analysed and compared. Further, it is observed that relays can be utilised to boost the capacity of lower frequency component carriers ensuring better capacity fairness among the users.

Frequency-Translational Quadrature-Hybrid Receivers for Very-Low-Noise, Frequency-Agile, Scalable Inter-Band Carrier Aggregation

A frequency-translational quadrature-hybrid receiver is proposed that achieves wideband input matching for a reflective low-noise-amplifier input impedance and enables the realization of wideband, concurrent receivers. Frequency-agile, inter-band carrier aggregation is realized from a single antenna through RF signal sharing and quadrature-hybrid-coupler daisy chaining. A 1.1 V 65 nm CMOS prototype chip is demonstrated that has a sub-1 dB minimum NF, a 12 MHz to 70 MHz RF bandwidth, a +8 dBm $IIP_{3}$ , and a −15 dBm $B_{1dB}$ and consumes <58 mW per channel. The prototypes have been integrated into a demonstration system that features 4-band inter-band carrier aggregation with modulated carriers placed between 0.69 and 2.1 GHz and received with an EVM <2.8%.