A 144-element phased array transceiver is realized using a modular tiled approach that supports 802.11ad, MCS12 single carrier 16-quadratic-amplitude modulation (QAM) 4.6 Gbps, in the 60-GHz band. It consists of a system-on-a chip (SOC) (MAC/PHY/BB to IF) in 28-nm CMOS, and one IF-to-60-GHz transceiver master chip driving twelve 60-GHz phased array transceiver slave chips fabricated in a 40-nm CMOS. Using the master-slave configuration, the 60-GHz transceiver with 12 phase-controlled TX/RX slices is expanded to 144 phase-controlled slices. Each final TX/RX slice is then connected to two patch antennas on LTCC substrate. A tiled approach is used to create the 288 patch antenna array out of six identical tiles each with two slave 60-GHz transceivers connected to a 48-element antenna array. The single tile phased array with 48 antennas has a measured beam steering scan angle of 60 degrees in azimuth and 10 degrees in elevation. The full phased array transceiver with 288 antennas has a measured over the air (OTA) max effective isotropic radiated power (EIRP) of 51 dBm at saturated power (PSAT), and EIRP of 44.8 dBm with -22 dB EVM for MCS12 (16QAM-4.6 Gbps) at broadside. It has an OTA measured sensitivity of -87.3 and -80.4 dBm for MCS9 (QPSK-2.5 Gbps) and MCS12, respectively, at broadside. A packet error rate of 10(-5) was measured for MCS9 and MCS12 with an OTA input power of -85 and -77.5 dBm, respectively, for the full phased array transceiver at broadside.
The 802.11ad standard (WiGig) provides throughput speeds of multi-Gb/s covering tens of meters and uses beamforming in the four 2GHz-wide channels in the 60gHz ISM band. Conventional backhaul solutions, on the other hand, are designed with high gain directional antennas with no electronic beam steering and have high cost for installation and alignment of antennas. This paper presents a full-featured 802.11ad chipset with 144-element phased array using a tiled approach and CMOS IPs developed for WiGig to address low-cost municipal WiFi, small-cell backhauling, and broadband to home covering the last mile. Designed with a link budget of 120dB+, the phased-array solution can be mounted on top of lamp posts and roof-top buildings covering a 200m LOS, and with tens of hops a range of 2km can be covered from a single point of fiber. Moreover, the steerable phased arrays enable dynamic routing optimization between hopping nodes in a mesh network.
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 + Release11, 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.
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.