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Integrated Access and Backhaul based 5G Connectivity for Rural Indian Sectors : Ending the Digital Divide

Biswas Ardhendu Shekhar, Sil Sanjib, Bera Rabindranath, Mitra Monojit

International Journal of Electronics and Telecommunications

2021

Vol. 67, No. 4

655--663

The world is heading towards deployment of 5G commercially by the year 2020. But providing broadband 5G connectivity to remote rural regions is a significant challenge. Fiber connectivity has attempted to penetrate rural regions but last mile connectivity is still a problem in many rural sectors due to improper land demarcation and hostile terrain. A scheme which is based on the Integrated Access and Backhaul (IAB) concept is proposed to provide last mile 5G connectivity to satisfy the broadband needs of rural subscribers. A wireless 5G downlink environment following 3GPP NR specifications with a significantly high throughput is simulated. The last mile link is provided through a 28GHz carrier from a proposed IAB node delivering a data throughput of 4.301 Gbps for single-user carrier aggregation and 5.733 Gbps for multi-user carrier aggregation which is quite promising for broadband service, like high-speed Internet and streaming video. The results presented in this work are observed to agree favourably with the results of other researchers in the field.

Geochemistry and growth morphology of alkali feldspar crystals from an IAB iron meteorite : insight into possible hypotheses of their crystallization

Słaby E., Karwowski Ł., Majzner K., Wirth R., Muszyński A., Birski Ł., Simon K., Domonik A., Moszumańska I., Orłowski R.

Annales Societatis Geologorum Poloniae

2017

Vol. 87, No. 2

121--140

Alkali feldspar crystals have been recognized in the troilite-graphite nodules of the Morasko IAB iron meteorite. Their chemical, microtextural and structural properties were studied using electron microprobe analysis (EMPA), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), transmission electron microscopy (TEM) and Raman spectroscopy. The feldspars occur as perthitic or antiperthitic intergrowths, whereas the albite lamellae are perfectly twinned. The structural properties reveal intergrown phases with fairly disordered patterns. The electron microprobe analyses demonstrate that the intergrown phases are mainly rich in sodium or potassium, resulting in compositions that are close to those of albite or orthoclase. The compositions, calculated on the basis of a segmented perthite-antiperthite image, showed that the Or-to-Ab proportions in the homogenized crystals were almost 0.3:0.7, thus indicating that the anorthoclase crystallized under high-temperature conditions. Two hypotheses of crystal formation could account for these characteristics: crystallization from a melt or from a metasomatic solution. Relics with evidence of metasomatic replacement of former minerals were not found. Accordingly, this work focuses on arguments that support the other hypothesis. Large ion lithophile elements (LILEs, e.g., Ba, Sr, Rb, LREE, Pb, and Ga) were used to track the origin of the crystals. Their concentrations indicate crystallization from a parent melt strongly depleted in LILEs. Alkali feldspar is commonly a product of a highly differentiated melt. However, highly differentiated melts are typically enriched in LILEs, which here is not the case. The melt that crystallized the feldspar cannot be related to impact-induced partial melting of the chondritic material alone. The derived melt probably was contaminated by silica-rich target material during interaction between the IAB projectile and the target material and was accompanied by metal and sulphide melts that were both immiscible with a silicate melt.