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A novel parallel optical delay detector (PODD) is proposed for angle-of-arrival (AOA) measurement of a microwave signal with selective measurement range and signal-to-noise (SNR) enhancement. The PODD is experimentally demonstrated by using a dual parallel Mach-Zehnder modulator. The noise robustness enhancement is experimentally investigated. Based on the proposed PODD, the measurement error for the full range can be less than 0.02 radian (0.71% of full measured range).

National Tuberculosis (TB) Treatment Centre, Makerere University Medical School and Joint Clinical Research Centre, Kampala, Uganda.To evaluate the introduction of a polymerase chain reaction (PCR) based assay for identification of the Mycobacterium tuberculosis complex (MTC) into routine practice.Routine diagnostic specimens were processed and inoculated into Bactec 12B vials and monitored daily. At a growth index (GI)or =10, 0.5 ml of the 12B broth was removed and assayed with PCR. The same 12B vial was analyzed using the Bactec NAP method at GIor =500. Vials at various levels of GI were included. Recurrent cost and time required to perform PCR and NAP were compared.Initially, 71 specimens were analyzed; of these, 68 were NAP-positive while 69 were PCR-positive for MTC. PCR resulted in a 75% reduction in cost for a single test compared with Bactec NAP. PCR has been successfully incorporated into routine practice, and 432 samples have been analyzed. In addition, isolates from solid media were also well identified by PCR. With PCR, more samples can be analyzed at a time, it is faster and is less labor intensive.PCR is a reliable and cheaper alternative for the identification of MTC.

A single in-building optical fibre network can efficiently deliver wired and wireless services. Point-topoint architectures using POF are attractive for small buildings; for large buildings SMF-based all-optical bus architectures using weighted tap couplers are preferable.

We demonstrated the simultaneous transmission of a multiband 4G (i.e. LTE-A) and gigabit/s baseband signals over 35m of 1mm core diameter PMMA GI and SI POFs. The transceiver consists of a Fabry-Perot 650nm laser diode and p-i-n photodiode. The LTE-A was transmitted with Analog-RoF technique, using a simple equalisation method. 12 LTE-A bands and a 1.9Gb/s 4-PAM baseband signal were co-transmitted over the GI-POF. 7 LTE-A bands and a 1.7Gb/s 4-PAM signal were co-transmitted over the SI-POF. The equalisation technique showed to be an effective method to increase the link throughput, hence enabling POF to be an excellent candidate for an in-home network infrastructure.

Using a novel optical frequency multiplication technique, microwave signal carriers exceeding 20-GHz are delivered to a significantly simplified remote radio access unit fed by a multimode fibre link having modal bandwidth below 2-GHz. Measurement results show that the remotely generated carriers have very narrow linewidths below 20-Hz. Thus existing in-building silica multimode fibre infrastructure, and the emerging polymer optical fibres may be used to not only transport fixed data services such as gigabit Ethernet but also to transparently distribute in-doors, signals of present WLANs as well as future broadband WLAN services leading to significant system-wide cost reduction

Many different services with widely ranging signal characteristics are to be supported in in-home networks: fast data transport (e.g. Gbit Ethernet), video, high-Q audio, and control signals. These services may use wired or wireless connection to the end user. In order to support them in parallel, low-cost methods for multiplexing signals independently on a POF in-home network have to be devised. This paper reports recent results in exploring novel multiplexing methods: mode group diversity multiplexing, adaptive subcarrier multiplexing using higher-order passbands in combination with multilevel coding, and optical frequency multiplying for transporting microwave signals for e.g. broadband wireless LAN and body area networks. The applications in broadband multi-service scalable in-building networks are highlighted.

Using a novel optical frequency multiplication concept, narrow linewidth microwave carriers exceeding 20 GHz are delivered to a remote radio access point fed by a modal-bandwidth-limited GIPOF fibre downlink. Important for next-generation in-building WLANs.

A novel integrated step-wise optical tunable delay line for microwave beam steering towards in-home devices is designed and characterized. The measured delay times agree with the design values within 6.7%.

We demonstrate the successful co-transmission of 7 standard-compliant 64-QAM LTE-A bands and 2Gb/s 4-PAM over 35m of 1mm core diameter GI-POF and 3.5m LOS and NLOS wireless links. This demonstrates the suitability of POF for the next-generation home-appliance wireless-wired services. Th.2.P2.SC7: Access, Local Area and Home Networks

Mode group diversity multiplexing integrates multiple services in a single in-home multimode fibre network, by deploying mode groups in parallel. Compensating mode-mixing with cheap electrical signal processors, its functionality equals wavelength multiplexing at lower costs.

Recent trends in optical signal handling technologies are reviewed, which enable cost-effective integration of multiple services, increase data transport capabilities, and extend the reach in access and in-house networks

Using discrete multi-tone modulation with up to 64-QAM mapping, 24-Gb/s transmission is experimentally demonstrated over 730 m of MMF by direct modulation of an 850-nm VCSEL and direct detection with a MMF receiver.

Recent advances in high-speed data transport techniques over POF networks are reviewed. New approaches such as microstructured polymer fibres, mode group diversity multiplexing, and optical frequency multiplying to carry microwave signals for wireless applications promise even further extension of the POF system capabilities.

A novel system concept is presented to transport microwave signals over an in-house graded index polymer optical fibre network, in order to feed the radio access points in high-capacity wireless LANs. By employing optical frequency multiplying, the network's intrinsically limited bandwidth is overcome. The feasibility of this concept to carry data at several hundreds of Mbit/s speed for various microwave signal formats at carrier frequencies in the tens of GHz range is shown. The concept enables cost-effective system implementation and easy upgrading by offering data signal transparency. It can readily be integrated with other system technologies such as wired Gigabit Ethernet in a single multi-service in-house polymer optical fibre network.