Sharif Digital Repository

Because of their exclusive features, millimeter wave directive mesh networks can be considered for small cell backhaul support in urban environments. For this purpose, a network of closely spaced stations has been considered with very directive line-of-sight links operating in the 60-GHz band. An attempt is made to evaluate channel response and interference behavior in such a network, taking into account the effect of building blockage. A simple grid of building blocks is considered as the propagation environment, and wave propagation is simulated using 2.5-dimensional (2.5D) ray tracing (2D with ground effect) to calculate the received signal at different nodes in the network. The results... 

A fully integrated 802.11ad/WiGig compliant 60 GHz transceiver is presented in a 130 nm SiGe BiCMOS technology. Encompassing an area of 2.3 mm × 2.16 mm = 4.97 mm2, the transceiver covers the entire 60 GHz band, from 57 to 66 GHz. Within this span, the RX NF, TX OP1dB, and PLL RMS jitter is better than 5.5 dB, + 13.5 dBm, and 7°, respectively. The transceiver is packaged in 1) a system-in-package substrate with industry standard WR-15 transition providing an approximate 1 dB insertion loss, and 2) a cost-effective 7 × 7 mm2 organic BGA package with integrated transmit and receive antennas providing 8 dBi gain. In system-level testing, the transceiver is fully compliant with all TX EVM and RX... 

An efficient ray tracing technique for channel modeling of an ultrawideband signal in 60 GHz band is introduced. In the usual method, field calculations at many frequencies must be done where has a high computational cost. We have introduced a novel method using Chebyshev polynomials interpolation to reduce the computational cost. Some propagation parameters such as gain and root mean square (RMS) delay spread are obtained and compared to the other method  

To evaluate the performance of the distributed medium access control layer of the emerging ultrawideband and 60-GHz millimeter wave (mmWave) wireless personal area networks based on ECMA-368 and ECMA-387 standards, the first step is to determine the beacon period length (BPL) of the superframe in a given network. In this paper, we provide an analytical model for the probability mass function (PMF) of the BPL as a function of the network dimensions, number of beaconing devices, antenna beamwidth, and the transmission range of the devices. To enable devices with steerable directional antennas in the ECMA-387 standard to have simultaneous communications with neighbors in their different antenna... 

A probabilistic method is developed here to model the beacon period length (BPL) defined in the ECMA-368 and ECMA-387 standards for the distributed reservation protocol. The model computes the probability mass function (PMF) of the BPL in a superframe which will be used in modeling of throughput, delay, fairness, power and other major distributed medium access control layer parameters of the emerging ultra wideband and 60- GHz millimeter wave wireless personal area networks. The model relates the PMF of the BPL to the network density, antenna beamwidth, and the transmission range of the devices assuming that the devices are distributed in an outdoor environment based on Two-dimensional... 

In this paper a directive mesh network operating in the 60 GHz unlicensed band is considered for backhaul support for a small cell mobile network in an urban environment and interference between network links is analyzed. It is observed that while non-line-of-sight stations are adequately isolated by antenna directivity, interference can affect link performance in links that fall in line with each other, namely, line-of-sight links. Seeing as back-to-back links may occur in the proposed network between stations situated within long straight streets, the resulting interference can cause a decrease in network capacity by preventing simultaneous transmission on links. Here, the use of... 

To evaluate the performance of distributed mediumaccess control (MAC) layer of emerging ultra wideband (UWB) and 60-GHz millimeter wave (mmWave) wireless personal area networks (WPANs) based on distributed reservation protocol (DRP) of ECMA-368 and ECMA-387 standards, we provide an analytical model for the probability distribution of steady state throughput as a function of the network dimensions size, number of devices, antenna beamwidth, transmission range, bit error rate (BER), antenna disturbance rate (ADR), aggregation length, payload size, and incoming frame rate. Using this model, the optimal payload size is computed as an example of optimization problem.We also propose a formula for... 

This paper presents a sequence of affordable methods applied to diagnose a millimeter-wave system-in-package. The module used in this paper is a 60 GHz transceiver with a waveguide interface, designed to transmit 8 dBm of saturated power. It consists of a flip-chipped RFIC, a multi-layer organic substrate, a metal enclosure with a standard waveguide interface, passive components and a 30-pin connector. The first measured output power was 3 to 6 dB below the desired value over the 60 GHz band. Thus, all parts of the module were thoroughly investigated to detect the cause of power drop. By 3-D electromagnetic simulation of the enclosure, the cavity modes and power leakage in the enclosure were... 

A phase-coherent technique for multiple all-digital phase-locked loops (ADPLLs) is presented and developed in this paper to target a 57-63-GHz multiple-input multiple-output (MIMO) transmitter (TX) with a digital beam-steering capability. The ADPLL TX chains are first fabricated in nanoscale CMOS and then time-synchronized and frequency-phase locked by a field-programmable gate array (FPGA) evaluation board. The calibration approach for phase alignment is carried out using a cancellation method to acquire the out-of-phase state within two ADPLLs. The accuracy of beam steering and phase alignment is investigated and analyzed based on a time-domain model for ADPLL to consider the impact of...