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Rather than perpetuate the anniversary as an engineering and communications achievement, this exhibition positions the OTL as both a conduit for colonial expansion and a complex zone of cross-cultural contact and exchange. The exhibition follows the physical development of the OTL, beginning with John McDouall Stuart's explorations as the foundation for the line, and moves through the "Southern", "Central" and "Northern" sections. The twenty-second of August 2022 marked the 150th anniversary of the completion of the Overland Telegraph Line (OTL), a communication wire that travelled across the Australian continent, from Adelaide to Port Darwin, and connected the Australian colonies to the British Empire and to the rest of the world via a subsea cable (see Figures 1 and 2). [Extracted from the article]

A new transmission scheme is presented for a two-hop relay network including two AF relays, considering physical layer security where relays are not able to detect signal with an acceptable bit error rate (BER) but the combined received signal is detected with an acceptable BER at the final receiver. It is assumed that there is no direct path between the transmitter and the receiver (relay network without diversity). Adaptive modulation and coding is utilised at the transmitter and transmission powers of the transmitter and of the relays are continuously adapted provisioning individual average power constraint for each node. Numerical evaluations show that an acceptable performance degradation is seen by the proposed secure relaying scheme compared to the optimum relay selection scheme without security constraint. [ABSTRACT FROM PUBLISHER]

Cooperative relaying exploits the broadcast nature of wireless channel and extracts spatial diversity in distributed manner. In this paper, we investigate the performance of an infrastructure-based multi-antenna relay network in absence of direct link. A closed-form expression of outage probability has been derived when the cooperating relays coherently combine the received signals and destination select the best copy of the received signals. The effect of number of relay antennas and relay placement on the system performance has also been studied. [ABSTRACT FROM AUTHOR]

Recently, the cooperative communication has been employed as an effective technique to combat the effects of channel fading and to conserve the energy in wireless networks. The impact of cooperative communication on transmission rate, however, has not been well addressed yet. In this paper, we address the transmission rate enhancement issue via adaptive relaying in wireless networks. For a given transmitting power level and a desired probability of success, we investigate how much average transmission rate can be increased by adaptive relaying. Moreover, we study the impact of maximal ratio combiner and energy constraint on adaptive relaying. The extensive evaluation results reveal that the average transmission rate can be substantially improved through such adaptive cooperation. [ABSTRACT FROM PUBLISHER]

The article presents information on the evolution of radio broadcasting systems in Spain. It is stated that the year 1925 was a special one for Spanish radio, because on June 17, King Alfonso XIII inaugurated Union Radio's new broadcasting station. Some of the earlier literary works that concentrated on the issue, includes Friedrich Arnheim's Rundfunk als Horkünst, Paul Deharme's Pour un art radiophonique, and Ramón Gómez de la Serna's "Hay que matar el morse!." During the 1970s and 1980s, the interest in radio and mass communication also increased in Spain.

A novel design of a microwave photonic filter with infinite impulse response is demonstrated. The design is based on a dual drive modulator with an optoelectronic feedback loop. The stopband of the filter can be switched to passband and vice versa by switching the bias point of the dual drive modulator. Measured results confirm the theoretical expressions and demonstrate a rejection ratio and frequency selectivity which is greater than 30 dB. [ABSTRACT FROM AUTHOR]

The differential rain attention is a significant propagation effect potentially degrading the interference between systems in the fixed-satellite service and radio-relay systems using the same frequency band. In the paper, a method to predict the carrier-to-interference ratio (CIR) degradation due to rain differential attenuation valid for single/double site diversity systems operating in a single polirization, is extended to include systems operating in a dual polarization mode. The modified method is again based on a model of convective rain cells as well as on the lognormal assumption for the point rain rate distribution at the location under consideration. Another important point of the paper is the presentation of some simple parametric expressions for the calculation of CIR statistics. Nucmeical results are presented concerning simulated interfered satellite links using both double site diversity and frequency re-use technique. Because of lack of available experimental data, our attention has been concertrated on the examination of the reliable design and the optimum coordination between the adjacent systems. Some very useful conclusions are deduced. [ABSTRACT FROM AUTHOR]

This paper highlights preliminary results from the analysis of the first year's data from the multi-channel scanning microwave radiometer (MSMR) onboard India's Oceansat-1 satellite, over the climatologically and geologically important Antarctic and Southern Ocean regions. Weekly averaged microwave brightness temperature images formed using the MSMR data clearly demarcated open water and sea ice regions. Different levels of ice concentration also showed up as different brightness temperature values. Signatures of several large and prominent continental features like the Trans-Antarctic Mountain ranges, Gamburtsev sub-glacial mountain, Wilkes and Aurora sub-glacial basins and the Ross Ice Shelf were seen in these images. Some quasi-circular coastal 'eddy' like features were also observed in sea ice regions off the eastern Antarctic coast. These studies reveal the potential of Oceansat-MSMR for long term monitoring of the polar regions of the Earth. [ABSTRACT FROM AUTHOR]

Examines the history and operations of Eastern Microwave Communications Corp. during cable's pre-satellite era in the United States. Use of microwave technology to import signals; Role of Eastern Microwave in the establishment of cable programming; Evolution of cable television; Name change of Eastern Microwave into EMI Communications Corp.

Discusses the history of television in Chicago, Illinois. Evolution of Chicago television programming; Contributions of William Crawford Eddy to WBKB; Importance of microwave relay transmissions and networking; Role of Ted Mills in the development of Chicago School of Television; Techniques and formats used by Chicago televisions.

Reports on the U.S. Navy's deployment of E-6A Hermes radio relay aircraft. Replacement of TACAMO communications aircraft; Command and control link of the Navy to the Trident force; Maximization of the survivability of E-6A.