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A breadboard of a three-layer printed reflectarray for dual polarization with a different coverage in each polarization has been designed, manufactured, and tested. The reflectarray consists of three layers of rectangular patch arrays separated by a honeycomb and backed by a ground plane. The beam shaping for each polarization is achieved by adjusting the phase of the reflection coefficient at each reflective element independently for each linear polarization. The phase shift for each polarization is controlled by varying either the x or y patch dimensions. The dimensions of the rectangular patches are optimized to achieve the required phase shift for each beam at central and extreme frequencies in the working band. The reflectarray has been designed to produce a contoured beam for a European coverage in H-polarization in a 10% bandwidth, and a pencil beam to illuminate the East Coast in North America in V-polarization. The measured radiation patterns show that gain requirements are practically fulfilled in a 10% bandwidth for both coverages, and the electrical performances of the breadboard are close to those of a classical dual gridded reflector. Index Terms--Contoured beam, dual gridded reflector, dual polarization, multilayer, printed arrays, reflectarray.

Pneumocystis carinii (PC) pneumonia is one of the hallmarks of AIDS; for 60 to 65 percent of AIDS patients, the diagnosis of PC pneumonia leads to the diagnosis of AIDS, and 80 to 85 percent have PC pneumonia at some time. The mortality rate of Pneumocystis carinii pneumonia is 25 percent. There has been some indication that, in addition to antibiotic treatment, the use of corticosteroids may provide some benefit for AIDS patients with PC pneumonia. For this reason, a placebo-controlled study was designed to confirm if this was indeed the case. Before the study was completed, the use of corticosteroids was, in fact, found to be so beneficial that ethics demanded the study be cancelled so that no patient would be deprived of the treatment. Although researchers had anticipated enrolling 80 patients, only 23 actually participated; the study was terminated when statistical significance was achieved. All patients were treated with the antibiotic combination trimethoprim-sulfamethoxazole. Twelve patients also received corticosteroids. Nine of the patients who received corticosteroids as adjunctive therapy were discharged from the hospital, compared with only 2 of the 11 patients who received antibiotics alone. Nine of the 11 patients who were not treated with corticosteroids developed respiratory failure, in contrast with only 3 of the 12 corticosteroid-treated patients. There were no acute side effects that required discontinuing the corticosteroids. However, these agents may increase the likelihood of some other complications of AIDS, such as mycobacterial infection and Kaposi's sarcoma. The high mortality among the patients who received only antibiotics prevented any evaluation of this possibility. (Consumer Summary produced by Reliance Medical Information, Inc.)