A cognitive radio system needs accurate knowledge of the radio spectrum it operates in. Blind modulation recognition techniques have been proposed to discriminate between single-copyright and multicarrier modulations and to estimate their parameters. Some powerful techniques use autocorrelation- and cyclic autocorrelation-based features of the transmitted signal applying to OFDM signa... https://www.roneverhart.com/Medline-Wheelchair-Arm-Trays-TRAY-ARM-WHEELCHAIR-ADJUSTABLE-LEFT-MDSR009636/