This paper presents a dual-polarization antenna with high spectral efficiency for transmission application distance at 60 GHz. The dual-polarization antenna is integrated with the receivers through flip chip on the LTCC substrate at 60 GHz. The receiver front-end composes of a low noise amplifier and demodulator fabricated in 65-nm CMOS process. The conversion gain is higher than 14 dB and the noise figure is lower than 6 dB from 57 to 66 GHz. The total data rate of the proposed system's spectral efficiency is up to 12 bit/s/Hz for wireless measurement and the EVM is below 5.5 %.

/pdf/a-high-spectral-efficiency-receiver-at-57-66-ghz-using-65-nm-11bcm176mo.pdf

A High Spectral Efficiency Receiver at 57-66 GHz Using 65-nm CMOS in LTCC Package With Polarization MIMO

The channel capacity of indoor 60 GHz radio is studied in this work from the diversity and the directivity viewpoints of multiple input multiple output (MIMO) wireless systems. To characterize the diversity and directivity (DnD) tradeoff of using planar antenna arrays (PAA) in indoor 60 GHz channels, a hybrid architecture for dual-polarized PAA (DP-PAA) is employed to exploit the potential advantages between the two extremes of this DnD tradeoff. A DP-PAA under this hybrid architecture can either be configured to apply the spatial multiplexing (SM) gain of MIMO channel diversity, or to enhance the array gain with beamforming directivity. Furthermore, the polarization diversity of DP-PAA can provide the system with a minimum degree of SM gain and compensate the coverage hole of a single-polarized PAA. Through theoretical investigations and numerical simulations, we show that the indoor 60 GHz channel of using a hybrid DP-PAA pair at both the transmitter and the receiver can approximately be modeled as a Kronecker MIMO channel. In addition, using the directivity of DP-PAA can lead to a higher channel capacity than using its spatial diversity under FCC's 40 dBm equivalent isotropically radiated power limit for indoor unlicensed 60 GHz links. This prevents the use of expensive high-dimensional MIMO to improve the channel capacity of indoor 60 GHz radio.

Diversity and directivity tradeoff in indoor 60 GHz MIMO channels: A case study with dual-polarized hybrid planar antenna arrays

The channel capacity of a multiple input multiple output (MIMO) system that uses a hybrid beamforming (HBF) mechanism for a 2×2 dual-polarized (DP) planar antenna array (PAA) is studied in this work for indoor 60 GHz channels. On one hand, the DP-PAA can resolve the receiving dead zone problem often seen in single-polarized PAA. On the other hand, the HBF architecture allows us to explore the advantages of spatial multiplexing or beamforming, or even both, in order to overcome the severe power loss problems often encountered from blocking or reflections in indoor 60 GHz radio propagations. Simulation results show that different architectures have advantages at different transmission power. In typical operating conditions of indoor 60 GHz radio, directivity offered by beamforming provides a higher capacity than does the spatial multiplexing provided by multiple baseband processing modules.

Empirical MIMO capacity of a 2×2 dual-polarized planar antenna array in indoor 60 GHz channels

An orthogonal polarization based MIMO transmission scheme is proposed to achieve over 10Gbps transmission for advanced 60GHz WLAN. As the proposed MIMO transmission scheme uses V(Vertical)/H(Horizontal) polarization directional antennas, stable 2X2 MIMO transmission is enabled even in LOS (line-of-sight) environment. A ray-tracing method is employed for computer simulation to evaluate channel capacity and BER performance of the proposed scheme in indoor conference room environments. The simulation results confirm that the proposed orthogonal polarization based MIMO transmission scheme achieves higher channel capacity than the conventional MIMO transmission using the same polarization antenna. Furthermore, this paper shows that BER performance depends on the location of transmitter and receiver as well as the beam-width of the directional antenna. BER performance is significantly degraded when the antenna height of the transmitter is the same as that of the receiver. On the other hand, better BER performance can be achieved when the antenna height difference is large.

Toshiaki Sasame

Papers

An Orthogonal Polarization Based MIMO Transmission for Advanced 60GHz WLAN