|Ph.D Student||Dyskin Aleksey|
|Subject||Synchronous Detection for Ultra-Wide Band Systems|
Operating at E-Band Carrier Frequencies with High
Speed Data Rates
|Department||Department of Electrical Engineering||Supervisors||Professor Dan Ritter|
|Professor Kallfass Ingmar|
|Full Thesis text|
The wireless communication systems operating at millimetre wave and sub-millimetre wave carrier frequencies make it possible to realize high speed point-to-point links with high data rates. However, the complex and power-hungry digital baseband signal processing of these broadband wireless communication systems is seen as a main drawback.
A possible solution to relax the complexity of the circuitry and the digital processing effort is by decreasing the spectrum efficiency and increasing the bandwidth accordingly. At millimeter-wave frequencies the channel bandwidth is often sufficiently high, so that simpler modulation formats can be utilized. Wireless communication systems that operate at frequencies of 28, 60, 71-86, 120 and 140 GHz can address this issue and can be used in various communication applications like short-range machine-to-machine, backhaul or indoor point-to-point networks. Despite the dramatically decreased spectrum efficiency, the increasing high-speed data rates resulting from the wide bandwidth become a very challenging issue to process. Analog-to-digital converter (ADC) and digital signal processor (DSP) implementation is seen as a major limitation due to their high power consumption and cost. This can be addressed by symbol sampling synchronization in case the symbol clock is coherent to the RF carrier or performing a carrier phase and frequency synchronization of the received signal in the analog domain with relatively low additional hardware effort and power.
Analog carrier recovery techniques continuously gain attention over the past years. A number of receiver front-ends and communication systems using analog carrier recovery have been reported recently. However, most of them operate at low frequencies, modulation (and hence hardware) dependent and were not implemented on chip.
In this research we present a modulation-independent carrier recovery technique. The technique uses a feed-forward controlled leakage transmission carrier, which is transmitted together with the modulated data. The leaked carrier is coupled to the carrier recovery circuit at the receiver side. The carrier recovery circuit comprises a frequency divider-by-two and a quadrature resistive PLL. A direct conversion E-band sub-harmonic mixer acts as a receiver front-end and receives a local oscillator (LO) signal from the carrier recovery circuit. The whole receiver, designed for BPSK modulation, was implemented in a SiGe 0.13um heterojunction bipolar transistor process. The receiver was tested with an E-band BPSK signal of up to 640 Mbps.
The main steps in the research were the systematic study and theoretical analysis of the E and Ka-band oscillation circuits (frequency dividers and voltage-controlled oscillators), system simulation of the entire receiver front-end and physical implementation of the system on chip (SoC).
The research was done in the Faculty of Electrical Engineering and Microelectronics Research Center, Technion -- Israel Institute of technology and in the Institute of Robust Power Semiconductor Systems (ILH), University of Stuttgart, Germany.