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In this paper, a low-profile, compact, high-gain antenna solution for four-port mm-wave broadband MIMO communication in a 5G environment is presented. The proposed antenna design consists of two rectangular patches connected through a corporate feed network and two quarter-wavelength square-shaped CSRRs on the ground plane. The overall size of the proposed four-port orthogonal MIMO configuration is 28.3 mm × 28.3 mm × 0.508 mm. The antenna operates on the 5G frequency bands of n257, n258, and n261 with an effective bandwidth of 3.9 GHz covering the range of 26.5 GHz to 30.4 GHz. The suggested MIMO antenna attained a peak gain of 11 dBi and radiation efficiency of 96% at 28 GHz resonating frequency. The MIMO configuration utilized DGS to minimize near-field coupling current at the ground plane, resulting in high port-to-port isolation of > 40 dB, and co-pol to X-pol isolation improvements of > 9 dB and > 19 dB in the boresight direction of E-plane and H-plane at 28 GHz resonating frequency. The antenna's superior diversity performance is supported by several performance metrics, including ECC(< 0.0001), DG(> 9.999 dB), CCL(< 0.12 bits/s/Hz), MEG (< −3 dB), and TARC. Moreover, the linear transmission property of the proposed MIMO antenna is also validated through the variation of group delay (< 0.6 ns) over operating frequency bands in the far-field region. [ABSTRACT FROM AUTHOR]

The global bandwidth inadequacy facing wireless carriers has motivated the exploration of the underutilized millimeter wave (mm-wave) frequency spectrum for future broadband cellular communication networks, and mmWave band is one of the promising candidates due to wide spectrum. This paper presents propagation path loss and outdoor coverage and link budget measurements for frequencies above 6 GHz (mm-wave bands) using directional horn antennas at the transmitter and omnidirectional antennas at the receiver. This work presents measurements showing the propagation time delay spread and path loss as a function of separation distance for different frequencies and antenna pointing angles for many types of real-world environments. The data presented here show that at 28 GHz, 38 GHz and 60 GHz, unobstructed Line of Site (LOS) channels obey free space propagation path loss while non-LOS (NLOS) channels have large multipath delay spreads and can utilize many different pointing angles to provide propagation links. At 60 GHz, there is more path loss and smaller delay spreads. Power delay profiles PDPs were measured at every individual pointing angle for each TX and RX location, and integrating each of the PDPs to obtain received power as a function of pointing angle. The result shows that the mean RMS delay spread varies between 7.2 ns and 74.4 ns for 60 GHz and 28 GHz respectively in NLOS scenario. [ABSTRACT FROM AUTHOR]

Abstract: High‐performance, wideband three‐stage power splitters based on substrate integrated waveguide (SIW) are presented. Broadband‐tapered microstrip transitions are used for feeding the SIW structures, which provide 7.5 GHz bandwidth from 21.5 to 29 GHz with return loss below −20 dB. In addition, various T junctions are tuned, not only to provide broadband performance up to mm‐wave frequencies but also offer low‐phase and amplitude imbalance when cascaded in multistage 1 × 8 splitters. 1 × 4 and 1 × 2‐T junctions are adjusted through parametric analysis to provide wide bandwidth of 3.5 GHz at 24.5 GHz and −15 dB reflection coefficient. The optimal microstrip transitions and T junctions are used to design a broadband, eight‐way power splitter with 15 dB return loss from 23.0 to 26.4 GHz and phase and amplitude imbalance of ±2.5° and ±0.8° dB, respectively. Furthermore, optimum positions of all inductive posts in terms of guided wavelength are also provided for assisting the direct design of mm‐wave, high‐performance power splitters. [ABSTRACT FROM AUTHOR]

This paper presents a 160 GHz center frequency pulsed 65 nm CMOS transceiver for short range radar applications. Four phased array transceivers were implemented in a single chip with antennas implemented in a BGA package. The implemented transmitter is capable of producing pulses of 100 ps widths (>20 GHz RF bandwidth) at a 160 GHz carrier frequency. The measured effective isotropic radiated power (EIRP) is 18.8 dBm for continuous wave outputs. The analog beam forming receiver achieves an overall gain of 42.5 dB, -14 dBm IP1dB, 7 GHz bandwidth, and a noise figure of 22.5 dB. The sliding window time-dilation baseband relaxes the output data rate and subsequent digital processing requirements. Fine grained duty cycling reduces power dissipation. The entire chip consumes 2.2 W from 1.2/1.4 V supplies in a 65 nm digital CMOS process. [ABSTRACT FROM PUBLISHER]

A low phase noise, wideband, mm-wave, integer-N PLL that is capable of supporting an 802.15.3c heterodyne transceiver is reported. The PLL can generate 6 equally spaced tones from 43.2 GHz to 51.84 GHz, which is suitable for a heterodyne architecture with FLO=(4/5)\timesFTRX. Phase noise is measured directly at the FLO frequency and is better than -97.5~dBc/Hz@1 MHz across the entire band. The reported frequency synthesizer is smaller, exhibits less phase noise, and consumes less power than prior art. In addition, the FLO tone corresponds to the fundamental of the VCO as opposed to a higher harmonic. [ABSTRACT FROM AUTHOR]

The design of short-range high-speed wireless networks for the 60 GHz band requires consideration of factors from a wide range of disciplines. Key system choices that make significant differences to the final cost and performance include the type of antennas, multiple access strategy and channel coding. In this paper we assume a coded orthogonal frequency division multiplexing (OFDM) system providing high-speed communications between low-cost terminals over indoor 60 GHz channels that are frequently non-line-of-sight. Under constraints of low transmit power and high path attenuation, we consider two practical options for using multiple low-cost ‘bond-wire’ antennas, compared with ideal monopole antennas at each terminal. For specified multiple access and channel coding schemes, we show that a sectorized strategy based on simple 2 element phased arrays can provide substantial benefits in system performance and flexibility. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]