Transceivers Tackle 4G Communications

A pair of highly integrated radio transceivers, the models AD9356 and AD9357 from Analog Devices, support 4G communications applications, including WiMAX and LTE. The transceivers integrate 12-b analog-to-digital converters (ADCs), digital-to-analog converters (DACs), complete RF-receive and RF-transmit signal chains, and on-chip frequency synthesizers. The AD9356 and AD9357 transceivers support the 2.3-to-2.7-GHz and 3.3-to-3.8-GHz ranges, respectively, with noise figure of 3 dB, covering existing WiMAX bands and channel bandwidths of 3.5, 4.375, 5, 7, 8.75, and 10 MHz. The new transceivers include two complete receivers as well as two complete transmitters for the support of multiple-input and multiple-output (MIMO) systems. The transmitters achieve +13 to +36 dBm output power at the antenna port. Designers can optimize receiver performance by configuring the transceivers to use a flexible, on-chip AGC (automatic gain control) algorithm. The transceivers include hooks for using incumbent baseband-controlled automatic gain control (AGC). The AD9356 and AD9357 are housed in 10 x 10-mm CSP BGA packages.