Flux density measurements of 23 pulsars

This paper reports the flux density measurements of 23 pulsar sat radio frequencies centered at 1540 and 4850~MHz, using the new pulsar observing system PDFB (Pulsar Digital Filter Banks) mounted at the 25-m radio telescope at Xinjiang Astronomical Observatory. The new de-dispersion system PDFB is described and the method of calibration for pulsar intensity measurements are introduced. Spectra indices of these pulsars were given based on our measurement combined with previously published data at other frequencies.