GXSC Beamformer Replaces ADMV4680 in Small Active Phased Array VSAT Terminals

Small active phased array VSAT terminals, leveraging the technical advantages of electronic beam scanning, no mechanical rotation, and adaptive satellite tracking, represent the mainstream direction for the next generation of portable satellite terminals. They achieve automatic satellite tracking and directional communication through coordinated transmission and reception by multiple antenna elements and chip-level beamforming.

During operation, the antenna array receives Ku-band satellite downlink signals. The beamforming chip performs multi-channel amplitude and phase calibration as well as beam synthesis, achieving directional gain summation and noise suppression. For uplink communication, channel power allocation and precise phase control are used to accurately direct the RF beam toward the satellite’s position, enabling data uplink transmission.

The GXSC beamformer is specifically tailored for Ku-band satellite user terminals. The chip integrates a complete transmit/receive beam control chain, covering the Ku-band satellite communication receive (10.7–12.7 GHz) and transmit (14–14.5 GHz) frequency bands. It incorporates four receive channels, four transmit channels, and corresponding power combining/power distribution networks, making it a highly integrated silicon-based beamforming chip. It offers comprehensive advantages, including high-precision amplitude and phase control, low-noise RF performance, high integration and miniaturization, and cascading scalability.

Both receive and transmit channels support 6-bit amplitude and 6-bit phase control. The chip uses a 4-wire standard SPI interface for register configuration and control, supporting offset adjustment, channel enable/disable control, and transmit/receive switching. Additionally, the single chip features five pin address lines (ADD0–ADD4) to enable serial control of up to 32 chips in an application. The chip supports internal beam storage, facilitating rapid switching between beam states. It is powered by a 1.2V main supply, with the digital I/O powered by 3.3V and implemented using standard 3.3V CMOS logic.

GXSC Beamformer Performance Specifications:

WLCSP (BGA) package; performance compatible with ADMV4680

CMOS process; low-cost mass production

High transmit and receive gain: ≥25 dB

High transmit output power: OP-1d8 power ≥11 dBm

Operating temperature: -40°C to 85°C

Receive: 10.7–12.7 GHz

Transmit: 14–14.5 GHz

Receive/transmit half-duplex

4T4R RF channels with integrated frequency division/synthesis networks

360° phase control range / 6-bit / LSB = 5.6°

31.5 dB amplitude control range / 6-bit / LSB = 0.5 dB

Receive NF: approximately 3 dB

Integrated temperature sensor

Integrated quantizing ADC

Integrated 4-channel power detector

Integrated beam storage

Transmit/receive state switching via dedicated pin

4-wire SPI control

WLCSP (BGA) surface-mount package

Integrated bias and channel control