Centralized Massive Multiple Input Multiple Output (MIMO) uplink detection techniques for baseband processing possess severe bottleneck in terms of interconnect bandwidth and computational complexity. This problem has been addressed in the current work by adapting the centralized Newton method for decentralized MIMO uplink detection leveraging several Base Station antenna clusters. The proposed decentralized Newton (DN) method achieves error-rate performance close to centralized Zero Forcing detector as compared to other decentralized techniques. Two hardware topologies, namely the ring and the star topologies, are proposed to assess and discuss the trade-off among interconnect bandwidth and throughput, in comparison with contemporary decentralized MIMO uplink detection techniques. As such the following findings are elaborated. On BS antenna cluster scaling for different MIMO system configurations, the ring topology provides high throughput at constant interconnect bandwidth, while the star topology provides lower latency with a deterministic variation in the hardware resource consumption. Due to strategic optimizations on the hardware implementation, additional user equipment can be allotted at a fractional increase in Field Programmable Gate Array resource consumption, improved energy efficiency, and increased transaction of bits per Joule. The ring topology can process additional subcarrier at a fractional increase in latency and improved system throughput.

Document describes e-book reading device for visually impaired people using two electronic refreshable Braille display units. A blind person has access to literature using Braille script, which consists of a alphabet being represented by combination of six pierced dots. Referred device uses a novel method of two tactile refreshable Braille cells consisting of six solenoid pins actuators, for conversion of alphanumeric character into Braille character. Secure Disk (SD) Card is used as a storage media. Text is printed with each word alternatively printed on either display unit. Characters are printed on a specific unit with a speed of 2 characters per second. The user reads words by placing both hands, one on each of the two tactile units. This device demonstrates functionality of AVR ATMEGA16 to design a robust embedded system. The advantages of the design are low complexity, portability and potential low cost of manufacture.

In the pursuit of energy efficiency in next-generation communication systems, approximate computing is emerging as a promising technique. In the proposed work, efforts are made to address the challenge of bridging the gap between the level of approximation and the Quality-of-Service (QoS) of the system. The application of approximate multiplication to wireless signal detection is explored systematically, illustrated by employing Truncated Multiplication (TM) on Quadrature Phase Shift Keying (QPSK) Minimum Mean Square Error (MMSE) detection. The irregularities induced by approximation in the multiplication operation employed in wireless signal detection are captured by the Approximate Multiplication Noise (AMN) model, which aids in the analysis of signal fidelity and resiliency of the system. The energy efficiency gains through approximation are highlighted in the approximation analysis. Signal fidelity analysis provides the capability to predict system output for varying levels of approximation, which aids in improving the stability of the system. The higher approximation levels are advantageous in low Signal-to-Noise Ratio (SNR) regimes, whereas lower approximation levels prove beneficial in high SNR regimes.

Indoor localization and mapping has become very crucial part of pervasive computing in recent times. Conventional outdoor techniques using GPS, Wi-Fi, and Cellular Networks have proved expensive and unconventional for indoor mapping. This document presents unique method of real time indoor localization and mapping using FM and ASK wave transceivers implemented using Phased Locked Loop and Field Programmable Gate Array (FPGA). Localization is procured with respect to three FM transmitters tuned at different frequencies. The geometrical wave model of these transmitters renders family of circles, where radius of each circle represents `Received Signal Strength Indicator' (RSSI) value corresponding to a particular transmitter. Solving this family of circles for a common point yields the location of object with respect to the transmitters. Object is installed with customized FPGA core and 3 FM receivers tuned to respective transmitter frequencies. RSSI values from each FM receiver are resolved into 4 bit digital values inclusively. FPGA acquire and process values from FM receivers via 3 parallel I2C buses which provide real time response. Unwanted continuous FM radiation is prevented by the use of wireless control over FM transmitters. Overall, a low cost solution is obtained to create a digital map which localizes and tracks objects in real-time.