Wideband beamspace squint user grouping algorithm based on subarray collaboration

The beam direction constrained problem is one of the important issues to be solved in millimeter-wave (mmWave) wideband communications when serving multi-user with squint beams whose direction varies with frequency. In this paper, we improve the number of simultaneous users served by collaboratively transmitting squint beams among multi-subarray at the base station (BS) end in a downlink multi-user line-of-sight (LoS) scenario, and reduce the interference among co-channel squint beams by a beam domain approach. The optimization problem of maximizing the number of users served in the system by transmitting beams in the two-dimensional beamspace of the planar antenna subarray is proposed and its suboptimal algorithm is given. Finally, the feasibility of the proposed method and the performance of the proposed algorithm are verified by numerical simulations.

HFSS Design of Hexagonal Monopole Antenna with FR4 Epoxy substrate – 7.34 GHz Ultra-Wide Band Antenna for Smart Shopping Application

The requirement to serve more users and provide more data at more incredible data speeds drives demand for wireless wideband communications. The Ultra-Wide Band (UWB) technology uses nanosecond-long pulses to span an extensive frequency range. The high bandwidth, low power consumption, and less fading due to multipath are attained in UWB communication technologies. This paper explains a hexagonal monopole antenna design using a high-frequency structure simulator (HFSS) and is further optimized for c better bandwidth. A hexagonal monopole antenna is designed using FR-4 epoxy metamaterial substrate. The optimum hexagonal bandwidth is attained at a span of 6.13 to 7.34 GHz frequency, and the polar gain is 1.2 dB. This paper provides the UWB antenna design; an optimized bandwidth is achieved as expected, the applications of smart marketing and a discussion of all relevant literature are carried out.

Variation of Ionospheric Narrowband and Wideband Performance for a 12,760 km Transequatorial Link and Its Dependence on Solar and Ionospheric Activity

The ionosphere provides a channel that is able to propagate electromagnetic waves for long-haul communications, allowing Non-Line-Of-Sight (NLOS) radio communications in the high-frequency band (HF). Nonetheless, its performance as a communications channel mainly depends on solar activity, as Earth’s diurnal and seasonal cycles modify the ionospheric ionization by the sun and consequently the channel performance. La Salle and the Observatori de l’Ebre have conducted oblique soundings of a 12,760 km ionospheric channel from Livingston Island (South Shetland Archipelago—Antarctica −62.7∘S, 299.6∘E) to Cambrils (Spain −41.0∘N, 1.0∘E) to evaluate this evidence and analyze the characteristics of this particular channel. The final goal of the project is to establish a stable communications link to be used as a backup for low throughput data transmission from the various geomagnetic and meteorological sensors located in the Spanish Antarctic Station. The aim of this paper is to confirm the relationship between the channel availability of narrowband and wideband communications and the resulting channel parameters with the solar and ionospheric activity for four consecutive sounding campaigns.