Dual-mode Ka-band upconverter for next-generation satellite communications

Analog Devices ADMV4530 Dual-Mode Ka-Band Upconverter features an Inphase/Quadrature (I/Q) mixer that is ideal for next-generation Ka-band satellite communications. An integrated low phase noise, fractional-N PLL with a VCO, and internal 2x multiplier generate the necessary on-chip LO signal for the I/Q mixer. These aspects remove the necessity for external frequency synthesis. The VCO uses an internal autocalibration routine that enables the PLL to select the required settings and locks in approximately 100μs.

The single-ended reference input to the PLL operates up to 500MHz and features internal reference dividers and a multiplier for added flexibility. Furthermore, the PFD comparison frequency can be up to 250MHz for integer mode and 160MHz for fraction-N mode.

The upconverter consists of an I/Q mixer that can operate in either I/Q mode with 500MHz of bandwidth or in IF (Intermediate Frequency) mode up to 3GHz of bandwidth, which allows various radio architectures and backward compatibility with legacy systems.

Immediately following the I/Q mixer are stages of gain and variable attenuation. The configuration can achieve a minimum 1dB compression point (P1dB) compression point of 19dBm, excluding the requirement for external stages of gain.

A programmable four-wire SPI enables adjustment of the quadrature-phase for optimum sideband suppression. Also, the SPI allows the nulling of LO feedthrough in IF mode. In I/Q mode, the LO feedthrough can be nulled by applying an external DC offset to the differential baseband I/Q inputs.

The upconverter is offered in a 40-terminal LGA package and is RoHS compliant.