Title :
An experimental digital beamforming array
Author :
Chang, D.C.D. ; Klimczak, W.N. ; Busche, G.C.
Author_Institution :
Hughes Aircraft Co., Segundo, CA, USA
Abstract :
A digital beamforming (DBF) array was fabricated and tested using commercially available parts to demonstrate beam agility and reconfigurability. The antenna portion of the DBF system consists of a 2*4 array of microstrip patch elements. The patch radiators are corner-fed square elements with a diagonal slot for circular polarization designed at 2.95 GHz in Duroid. The signal is split into I (inphase) and Q (quadrature phase) channels, and each channel is converted into a digital signal by an 8-b A/D (analog-to-digital) converter at a 5 MHz rate. The I and Q channels of each element are multiplied by an 8-b weight vector. The results of the I multiplications and Q multiplications are separately summed and then detected and converted to a DC voltage output proportional to the input received signal level. Numerous different patterns were obtained by varying the I and Q weight vectors appropriately. The experimental and theoretical patterns of a flat-top-beam and a difference pattern obtained by inverting the phase of half of the array are shown.<>
Keywords :
antenna radiation patterns; microstrip antennas; microwave antenna arrays; 2.95 GHz; A/D convertor; Duroid; beam agility; circular polarization; corner-fed square elements; diagonal slot; difference pattern; digital beamforming array; flat-top-beam; inphase channels; microstrip antenna; microstrip patch elements; quadrature phase channels; reconfigurability; weight vectors; Array signal processing; Bandwidth; Costs; Energy consumption; Low-noise amplifiers; Microstrip antenna arrays; Phase shifters; Power dividers; Radio frequency; Radiofrequency amplifiers;
Conference_Titel :
Antennas and Propagation Society International Symposium, 1988. AP-S. Digest
Conference_Location :
Syracuse, NY, USA
DOI :
10.1109/APS.1988.94337
