Radio over fibre (RoF) systems offer the bandwidth and flexibility for generation and distribution of future wireless access standards in an optical access architecture, which reduces the cost of the networks by centralising signal processing, and simplifying remote antenna sites. The use of optical communication systems as transport medium in RoF links is reducing the current access bottle neck between the wireless access standards and current wired access in a converged optical domain. The optical access networks are moving towards 10 Gb/s capacity with standards like 10GEPON, leaving a bottle neck between the wireless and optical access. This has led to a great research efforts in generation and distribution of high capacity (10 Gb/s and more) wireless links using RoF.

In this thesis the use of photonic techniques for generation, distribution, and detection of high capacity vector modulated wireless signals is investigated. This thesis is mainly dedicated to the generation of advanced spectral efficient wireless signals with modulation formats like quadrature phase shift keying (QPSK), multi-level quadrature amplitude modulation (M-QAM). The work presented in thesis is categorised in two parts: The first part deals with photonic techniques involving electrical coherent techniques for both modulation and demodulation, whereas the second part contains all optical incoherent techniques for modulation of demodulation of wireless signals. 

In the first part of this thesis, several system architectures for generation and detection of wireless signals are presented, which are numerically evaluated and experimentally demonstrated. A novel concept called photonic vector modulation (PVM) for generation of multi-level quadrature amplitude modulated (M-QAM) millimetre wave wireless signals is proposed. Based on this technique, signal generation of 10 Gb/s 16-QAM and QPSK wireless is presented in this thesis. Performance of the wireless signals generated using PVM is analysed in a reconfigurable WDM network. Based on the similar concept a demodulation technique for M-QAM wireless signals named photonic vector demodulation (PVdM) is presented. Both the PVM and PVdM techniques use electrical coherent techniques. The use of I/Q optical modulator for generation of dispersion tolerant differential phase shift keyed (DxPSK) and use of passive all optical demodulation of DxPSK signals using 1-bit delay Mach-Zehnder interferometer (DMZI) is investigated. 

In the second part of the thesis, a novel demodulation technique of wireless signals, which is both dispersion tolerant, and radio frequency transparent, using optical coherent detection and digital signal processing, is presented. The use of digital signal processing and homo-dyne coherent detection for high speed optical communication systems led to investigation of new modulation technique based on optical heterodyne mixing of free running lasers. Using this technique, wireless signal at record capacities of 20 Gb/s using QPSK modulation in the 75-110 GHz band is presented. Based on the similar technique, use of optical OFDM used in optical baseband links, for generation of high capacity wireless is also investigated, and wireless signal generation of 40 up to Gb/s using OFDM-QPSK modulation is addressed. 

The main outcome of the work presented in this thesis is listed as follows:
* A 10 Gb/s QPSK indoor wireless link demonstration in the 60 GHz band using photonic vector modulation.
* Non coherent demodulation technique transparent to RF frequency, and tolerant to dispersion based on optical coherent detection and digital signal processing.
* QPSK wireless signal generation based on heterodyne mixing of free-running lasers.
* \ Optical OFDM based 40 Gb/s wireless signal generation and coherent detection based demodulation.