Conceiving Inferential Prototypes of MIMO Channel Models via Buckingham’s Similitude Principle for 30+ GHz through THz Spectrum

2021-05-11T08:10:17+00:00

Facilitating newer bands of ‘unused’ segments (windows) of RF spectrum falling in the mm-wave range (above 30+ GHz) and seeking usable stretches across unallocated THz spectrum, could viably be considered for Multiple Input Multiple Output (MIMO) communications. This could accommodate the growing needs of multigigabit 3G/4G applications in outdoor-based backhauls in picocellular networks and in indoor-specific multimedia networking. However, in contrast with cellular and Wi-Fi, wireless systems supporting sub-mm wavelength transreceive communications in the outdoor electromagnetic (EM) ambient could face “drastically different propagation geometry”; also, in indoor contexts, envisaging pertinent spatial-multiplexing with directional, MIMO links could pose grossly diverse propagation geometry across a number of multipaths; as such, channel-models based on stochastic features of diverse MIMO-specific links in the desired test spectrum of mm-wave/THz band are sparsely known and almost non-existent. To alleviate this niche, a method is proposed here to infer sub-mm band MIMO channel-models (termed as “prototypes”) by judiciously sharing “similarity” of details available already pertinent to traditional “models” of lower-side EM spectrum, (namely, VLF through micro-/mm-wave). Relevant method proposed here relies on the “principle of similitude” due to Edgar Buckingham. Exemplar set of “model-to-(inferential)-prototype” transformations are derived and prescribed for an exhaustive set of fading channel models as well as, towards estimating path-loss of various channel statistics in the high-end test spectrum.

Towards a Description Synthesis of the Entanglement of the Substrate with the Interconnection Network, for Fast Modeling of 3D RF circuits

2021-05-07T08:15:48+00:00

3D chip stacking is considered known to overcome conventional 2D-IC issues, using Trough Silicon Via (TSVs) to ensure vertical signal transmission between data. If the electrical behaviour of 3D interconnections (redistribution metal lines and through silicon vias) used in 3D IC stack technologies are to be explored in this paper, the substrate itself is of interest, via Green Kernels by solving Poisson's equation analytically. Using this technique, the substrate coupling and loss in IC's can be analysed. We implement our algorithms in MATLAB. This method has been already used; but, it permits to extract impedances for a stacked uniform layers substrate. We have extended for any numbers of embedded contacts, of any shape. On a second hand, we grasp the background noise between any two points, in the bulk, or at the surface, from a transfer impedance extraction technique. With an analog algorithm, a strength of this work, we calculate unsteady solutions of the heat equation, using a spreading resistance concept. This method has been adapted to stacked layers. With this general tool of impedance field, we investigate on the problems encountered by interconnects, especially the vias, the substrate, and their entanglement. A calculation of thermal mechanical stresses and their effects on substrate crack (max and min stresses), devices (i.e: transistors) and hotspots, are made to track the performance. But, to well understand the interconnection incidence on 3D system performances, it is important to consider the whole electrical context; it seems relevant to consider the possible couplings between vias, not only by the electromagnetic field, but also by any possible energy transfer between interconnects; more generally, one of actual problem is to determine where the energy is really confined in such 3D circuits, before find solutions to limit pollutions coming from electro-magneto -thermal phenomena or background noises.

Transactions on Networks and Communications

Conceiving Inferential Prototypes of MIMO Channel Models via Buckingham’s Similitude Principle for 30+ GHz through THz Spectrum

Towards a Description Synthesis of the Entanglement of the Substrate with the Interconnection Network, for Fast Modeling of 3D RF circuits