Up/down converters and beamformers from Analog devices cover frequencies from 24 GHz to 43.5 GHz.
mmWave, the part of 5G that brings those happy faces on wireless carrier commercials, adds up/down conversion to the 5G RF signal chain. Beamforming, needed to direct signals to users, plays an important role. After all, who doesn’t need to download a movie in minutes or a song in seconds?
To get those bits to and from antennas, Analog Devices has released two sets of up/down converters and beamformers. All parts in the table are now in production.
| Part number | Frequency range | 5G NR bands |
| ADMV4828 beamformer | 24 GHz to 29.5 GHz | n257, n258, n261 |
| ADMV4928 beamformer | 37 GHz to 43.5 GHz | n260, b259 |
| ADMV1128 up/down converter | 24 GHz to 29.5 GHz | n257, n258, n261 |
| ADMV1139 up/down converter | 37 GHz to 48.2 GHz | n260, n259, n262 |
The up/down converters bring carrier frequencies from an intermediate frequency to full RF carriers and back. A second mode converts directly from baseband I/Q signals all the way to mmWave. An on-chip RF switch lets the devices operate in time-division duplex (TDD) mode, which increase spectral efficiency over FDD.
As upconverters, the two devices offer sideband rejection and carrier feedthrough optimization. They also use envelope detection for local oscillator (LO) feedthrough calibration. Both parts include 3-wire and 4-wire SPI interfaces for setup and communication with the host processor and beamformer ICs.
In addition to the converters, Analog Devices released two beamformers, each one handling different frequencies (see table). The ADMV4828 and ADMV4928 feature 16 configurable transmit and receive channels. Use additional parts for larger antenna arrays. The 16 channels use dual polarization, 8 horizontal and 8 vertical channels.
When operating as transmitters, the parts use separate amplifiers. Signal phase comes under the control of a 6-bit vector modulator. For amplitude modulation, the devices use 6-bit (0.5 dB resolution) and 5-bit (1 dB resolution) DVGAs. On-chip memory lets the devices store up to 2048 beam positions.
ADMV 4828 and ADVM4928 beamformer functional block diagram.
Filed Under: 5G, Cellular, mm Wave, phase shifters and trimmers, RFIC, up/down converters
