Real measurement study for rain rate and rain attenuation conducted over 26 GHz microwave 5G link system in Malaysia

In this paper, real measurements were conducted to investigate the impact of rain on the propagation of millimeter waves at 26 GHz. The measurements were accomplished using a microwave fifth generation radio link system with 1.3 km path length implemented at Universiti Teknologi Malaysia Johor Bahru, Malaysia. The implemented system consisted of Ericsson CN500 mini E-link, radio unit, rain gauge, and data logger. The measurements were attained and logged daily for a continuous year, with 1-min time intervals. Next, the MATLAB software was used to process and analyze the annual rain rate and rain attenuation, including for the worst month. From the analyzed results, it was found that at 0.01% percentage of time, the rain rate was 120 mm/hr; while the specific rain attenuation was 26.2 dB/km and the total rain attenuation over 1.3 km was 34 dB. In addition, the statistics acquired from the measurements for the worst month were lower than what was predicted by the international telecommunication union (ITU) model; around 51% and 34% for the rain rate and rain attenuation, respectively. The average percentage of error calculated between the measurements and predicted results for the rain rate and rain attenuation were 143% and 159%, respectively. Thus, it can be concluded that the statistics for the worst month in Malaysia is lower than what was predicted by the ITU model

Channel fading attenuation based on rainfall rate for future 5G wireless communication system over 38-GHz

In this paper, the effect of heavy rainfall on the propagation of a 38-GHz in a tropical region was studied and analyzed. Real measurement was collected, with a path length of 300 meters, for a (5G) radio linkage in Malaysia, installed at the Universiti Teknologi Malaysia (UTM) Johor Bahru campus. The employed system entails an Ericsson MINI-Link 38 E-0.6 mm, with a horizontal polarization (HP) antenna at the top integrated with a rain gauge and a data logger. Daily registered samples with a single minute span, for a full study period of 1 month, were collected and evaluated. The obtained rain rate was found as 56 mm/hr with a specific rain attenuation of 18.4 dB/km for 0.01% of the time. In addition to that, a calculated average rain attenuation of 5.5 dB for the transmission path of 300 meters length, was calculated. Based on these findings, a recommendation to update the International Telecommunication Union (ITU) specification of the rain attenuation for Malaysia is proposed. Based on the results, we suggest shifting the zone classification of Malaysia from zone P to zone N-P. Therefore, accurate design for future 5G systems would rely on more precise estimated attenuation levels leading to enhanced performance

Spatial variations of rain intensity over a short length propagation for 5G links based on a rain gauge network

Millimeter-wave (mm-wave) frequency range is among operating bands designated for terrestrial 5G networks. A critical challenge of link-budgeting in mm-wave 5G networks is the precise estimation of rain attenuation for short-path links. The difficulties are further amplified in tropical and subtropical regions where the rainfall rate has a higher intensity. Different models have been proposed to predict rain attenuation. The distance factor is an important parameter in predicting total attenuation from specific rain attenuation. This study investigates the distance factor based on rain gauge networks and measured rain attenuation at 26 GHz for a 300 m link in Malaysia. Considerable discrepancies between available models were observed especially when applied for shorter path links. Also, significant variability of rain intensity is observed from the rain gauge network. This study recommends further investigation of the distance factor for a shorter link. Hence, a measurement campaign incorporating rain gauge networks was established to examine spatial variations of rain intensity over a less than 1 km link. The motivation is to develop a suitable distance factor model for 5G mm-wave propagation

A methodology for precise estimation of rain attenuation on terrestrial millimetre wave links from raindrop size distribution measurements

Attenuation by atmospheric rain is the most significant impairment in millimetre wave frequencies (mmWave). Modern instruments could provide detailed measurements of rain, such as raindrop size distributions (DSDs). The analysis of DSDs could estimate their effects on past or co-located links measurements. This study presents propagation analysis in the mmWave bands using measurements of two terrestrial links working at 26 and 38 GHz carried out in Johor, Malaysia. Statistics obtained have been analysed in detail to extract any excess attenuation. The DSDs provided by a disdrometer have been used to estimate rain attenuation. The derived results show that the estimation can provide reasonable accuracy after extracting the wet antenna effects and having the advantage of the availability of measurements from various types of equipment

Rain Statistics Investigation and Rain Attenuation Modeling for Millimeter Wave Short-range Fixed Links

Millimeter wave (mmWave) communication is a key technology for fifth generation (5G) and beyond communication networks. However, the communication quality of the radio link can be largely affected by rain attenuation, which should be carefully taken into consideration when calculating the link budget. In this paper, we present results of weather data collected with a PWS100 disdrometer and mmWave channel measurements at 25.84 GHz (K band) and 77.52 GHz (E band) using a custom-designed channel sounder. The rain statistics, including rain intensity, rain events, and rain drop size distribution (DSD) are investigated for one year. The rain attenuation is predicted using the DSD model with Mie scattering and from the model in ITU-R P.838-3. The distance factor in ITU-R P.530-17 is found to be inappropriate for a short-range link. The wet antenna effect is investigated and additional protection of the antenna radomes is demonstrated to reduce the wet antenna effect on the measured attenuation

Rain Effect to A 60 GHz Broadband Wireless System’s Performance: Study Case In Purwakarta

Nowadays, world wide telecommunication researchers are developing 5G technology. One of most important key technology in 5G is Milimeter-Wave (mmWave). This study measure 60 GHz broadband wireless system performance because of it’s promising potentials. However, the use of these frequencies is quite sensitive to rain that resulting an atenuation in the channel. Therefore, this study proposes two schemes to address the problem. The first scheme is the use of QAM modulation (Quadrature Amplitude Modulation) and the second scheme is an addition of LDPC (Low Density Parity Check) code techniques. From the results of this study, by using 4-QAM modulation and LDPC coderate 1/2, the broadband wireless system’s performance on the second scheme is better compared to the first scheme with 8.33 dB Signal to Noise Ratio (SNR) value to provides BER (Bit Error Rate) 10-4Nowadays, world wide telecommunication researchers are developing 5G technology. One of most important key technology in 5G is Milimeter-Wave (mmWave). This study measure 60 GHz broadband wireless system performance because of it’s promising potentials. However, the use of these frequencies is quite sensitive to rain that resulting an atenuation in the channel. Therefore, this study proposes two schemes to address the problem. The first scheme is the use of QAM modulation (Quadrature Amplitude Modulation) and the second scheme is an addition of LDPC (Low Density Parity Check) code techniques. From the results of this study, by using 4-QAM modulation and LDPC coderate 1/2, the broadband wireless system’s performance on the second scheme is better compared to the first scheme with 8.33 dB Signal to Noise Ratio (SNR) value to provides BER (Bit Error Rate) 10-

Hybrid Satellite-Terrestrial Communication Networks for the Maritime Internet of Things: Key Technologies, Opportunities, and Challenges

With the rapid development of marine activities, there has been an increasing number of maritime mobile terminals, as well as a growing demand for high-speed and ultra-reliable maritime communications to keep them connected. Traditionally, the maritime Internet of Things (IoT) is enabled by maritime satellites. However, satellites are seriously restricted by their high latency and relatively low data rate. As an alternative, shore & island-based base stations (BSs) can be built to extend the coverage of terrestrial networks using fourth-generation (4G), fifth-generation (5G), and beyond 5G services. Unmanned aerial vehicles can also be exploited to serve as aerial maritime BSs. Despite of all these approaches, there are still open issues for an efficient maritime communication network (MCN). For example, due to the complicated electromagnetic propagation environment, the limited geometrically available BS sites, and rigorous service demands from mission-critical applications, conventional communication and networking theories and methods should be tailored for maritime scenarios. Towards this end, we provide a survey on the demand for maritime communications, the state-of-the-art MCNs, and key technologies for enhancing transmission efficiency, extending network coverage, and provisioning maritime-specific services. Future challenges in developing an environment-aware, service-driven, and integrated satellite-air-ground MCN to be smart enough to utilize external auxiliary information, e.g., sea state and atmosphere conditions, are also discussed

The Effect of Sand and Dust Storms (SDSs) and Rain on the Performance of Cellular Networks in the Millimeter Wave Band

Future cellular systems are expected to use millimeter-wave (mm-Wave) frequency bands in addition to the existing microwave bands under 6 GHz. Severe weather conditions, including sand and dust storms (SDSs) and heavy rainfalls, challenge reliable communications over wireless links at those higher frequencies. In such conditions, besides frequency-dependent path-loss, radio signals experience additional attenuation. The SDS attenuation is related to visibility, receiver distance to the storm origin point, soil type, frequency, temperature and humidity. On the other hand, the rainfall attenuation is affected by rainfall rate, polarization, carrier frequency, temperature and raindrop size distribution. Leveraging on experimental measurements carried out in previous works, a novel unified mathematical framework is introduced in this paper to include SDS/rainfall-dependent attenuation in the performance evaluation of terrestrial wireless cellular networks in terms of coverage probability, bit error rate (BER) and achievable rate in the mm-Wave band. Extensive numerical results are presented to show the effects of the different SDS/rainfall parameters on performance, showing that the degradation due to SDS is generally higher than that due to rain and may cause a reduction of even six orders of magnitude in the average achievable bit rate when the frequency increases from 28 to 38 GHz

Dual-band dual-polarized Microstrip Array for mm-Wave and sub-6 GHz Applications

In this paper, a compact dual-band and dual-polarized antenna array with integrated crossover for mm-Wave and sub-6 GHz band Wi-Fi applications is proposed. The proposed dual-band antenna is comprised of a 2x2 array operating at 26 GHz and 5.48 GHz (channel 96). The dual-band crossover consists of a microstrip-grounded CPW-microstrip interface transition. The measured design shows inter and intraband isolation better than 25dB with the crossover on the same plane with a maximum gain of 9.2dBi and 11.83 dBi for 26.25 GHz and 5.48 GHz respectively

Rain type classification for rain attenuation models in terrestrial link

Rain precipitation along the path from one base station to another base station is not constant due to drop size distribution of the rainfall and variation rain intensities. The signal level that propagates through rain is decreasing especially when the frequency used is above 10GHz. Rain classification is an important factor in rain attenuation studies. Rain can be classified in two broad categories which are convective rain and stratiform rain. Both categories have different effect on rain attenuation values due to different drop size distribution and different rainfall rates. However, what previous studies have not discussed is the attenuation prediction result for both stratiform and convective events. Hence, this study attempts to achieve the classification of rain by using probability method, determining 0.01% rain rate for stratiform and convective events and determining the suitable rain model that fits stratiform and convective rain. In order to choose good rain attenuation models, it is necessary to consider the link type and the experimental region. For this project, the chosen link is terrestrial link and the experimental region is tropical region. Therefore, the suitable rain models for this project are Garcia model, ITU-R 530-16 and Mello Pontes model. The duration of rain collection used for rain classification procedure is from 1996 to 1999. The percentages of time from complementary cumulative distribution function (CCDF) are used to determine which rain models suits stratiform and convective events. The result of rain classification shows that the totals numbers of stratiform and convective events are 631 events and 211 events respectively. Finding indicated that when using combined data and convective data, Mello Pontes is the most appropriate rain model to predict attenuation at terrestrial link. In addition, ITU-R 530-16, Mello Pontes model and Garcia model show good performance when using stratiform data as the three have similar attenuation values