Dmitriy Rozenblit

A Rel-12 2G/3G/LTE-advanced 2CC transmitter

This work presents a cellular transceiver capable of transmitting two simultaneous channels with an aggregate bandwidth of up to 40 MHz, supporting a 100 Mbps uplink rate. The transmitter has 8 RF output ports covering the cellular transmit bands within the 572–2100 MHz frequency range. It can support TX LTE-advanced Rel-12 Cat7, HSPA+ Rel-11, TDSCDMA Rel-9, and GSM/EDGE Rel-9. The 40 nm CMOS transmitter consumes 22 mA and 27 mA in 3G and LTE modes (at 0 dBm antenna power), respectively, including the PLL, DCXO and biasing for a single channel.

A temperature compensated VCO using feed-forward gain multiplication for cellular applications

A new LC-tank VCO to minimize frequency drift due to temperature variations for cellular applications is presented. By employing the feed-forward VCO gain multiplication technique, frequency drift is reduced by 83% without resorting to conventional temperature dependent biases and circuits. Additionally, the compensation circuit retains the original VCO behavior with no degradation in performance. A fractional-N PLL fabricated in 40 nm CMOS shows that the VCO draws 9 mA and the temperature compensation circuit draws 200 μA. Measurements show that the VCO has a tuning range of 46% (from 2890 MHz to 4560 MHz) and a phase noise of -102 dBc/Hz at 200 kHz offset centered at 3960 MHz at the PLL output before the divide-by-two circuit for 3G/LTE Band I.

A Rel-12 2G/3G/LTE-Advanced 2CC Transmitter

Carrier aggregation is a key feature of the 3GPP LTE-Advanced cellular network standard that combines multiple channels to support higher data rates and improve the utilization of fragmented spectrum holdings. This work presents a cellular transmitter capable of transmitting a maximum of four channels simultaneously, two contiguous channels in two bands, with an aggregate bandwidth of up to 80 MHz, supporting a 200 Mbps uplink rate. The transmitter has 8 RF output ports covering the cellular transmit bands within the 572-2025 MHz frequency range. It can support LTE-Advanced Release 12 Cat7, HSPA + Release 11, TDSCDMA Release 9, and GSM/EDGE Release 9. The 40 nm CMOS transmitter consumes 22 mA and 27 mA in 3G and LTE modes (at 0 dBm antenna power), respectively, including the PLL, DCXO, and biasing for a single channel.