author = "Bergano, Miguel and Rocha, Armando and Cupido, Luis and Barbosa, 
                         Domingos and Villela, Thyrso and Vilas Boas, Jos{\'e} Williams 
                         dos Santos and Rocha, Gra{\c{c}}a and Smoot, George F.",
          affiliation = "{University of Aveiro} and {University of Aveiro} and 
                         LC-Technologies and {University of Aveiro} and {Instituto Nacional 
                         de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and {Jet Propulsion Laboratory} and 
                         {Lawrence Berkeley National Laboratory}",
                title = "A high performance cost-effective digital complex correlator for 
                         an X-band polarimetry survey",
              journal = "SpringerPlus",
                 year = "2016",
               volume = "5",
               number = "1",
                pages = "487",
                month = "Dec.",
             keywords = "Logic design (hardware), Radioastronomy (astronomy, astrophysics 
                         and cosmology), Register-transfer-level implementation 
             abstract = "The detailed knowledge of the Milky Way radio emission is 
                         important to characterize galactic foregrounds masking 
                         extragalactic and cosmological signals. The update of the global 
                         sky models describing radio emissions over a very large spectral 
                         band requires high sensitivity experiments capable of observing 
                         large sky areas with long integration times. Here, we present the 
                         design of a new 10 GHz (X-band) polarimeter digital back-end to 
                         map the polarization components of the galactic synchrotron 
                         radiation field of the Northern Hemisphere sky. The design follows 
                         the digital processing trends in radio astronomy and implements a 
                         large bandwidth (1 GHz) digital complex cross-correlator to 
                         extract the Stokes parameters of the incoming synchrotron 
                         radiation field. The hardware constraints cover the implemented 
                         VLSI hardware description language code and the preliminary 
                         results. The implementation is based on the simultaneous digitized 
                         acquisition of the Cartesian components of the two linear receiver 
                         polarization channels. The design strategy involves a double data 
                         rate acquisition of the ADC interleaved parallel bus, and field 
                         programmable gate array device programming at the register 
                         transfer mode. The digital core of the back-end is capable of 
                         processing 32 Gbps and is built around an Altera field 
                         programmable gate array clocked at 250 MHz, 1 GSps analog to 
                         digital converters and a clock generator. The control of the field 
                         programmable gate array internal signal delays and a convenient 
                         use of its phase locked loops provide the timing requirements to 
                         achieve the target bandwidths and sensitivity. This solution is 
                         convenient for radio astronomy experiments requiring large 
                         bandwidth, high functionality, high volume availability and low 
                         cost. Of particular interest, this correlator was developed for 
                         the Galactic Emission Mapping project and is suitable for large 
                         sky area polarization continuum surveys. The solutions may also be 
                         adapted to be used at signal processing subsystem levels for large 
                         projects like the square kilometer array testbeds.",
                  doi = "10.1186/s40064-016-2109-5",
                  url = "http://dx.doi.org/10.1186/s40064-016-2109-5",
                 issn = "2193-1801",
             language = "en",
           targetfile = "bergano_high.pdf",
        urlaccessdate = "29 nov. 2020"