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To decrease cost and consumption of future wireless infrastructures, radio‐over fibre systems utilising 850 nm vertical cavity surface emitting lasers and standard single‐mode fibre (SSMF) are deserving particular attention in replacing the typical use of graded‐index multimode fibre (GI‐MMF). In the present work, a characterisation of noise and non‐linearities of these links is performed, followed by an estimation of their impact on the system dynamics and the quality of the received signal. This allows to show that very good and similar performances can be obtained through the utilisation of SSMF and GI‐MMF for the transmission of five long‐term evolution channels with 20 MHz bandwidth, confirming that the former, by the higher diffusion and lower cost per metre of the SSMF, can be put among the leading candidates for the realisation of fourth‐generation (4G) and 5G wireless networks. [ABSTRACT FROM AUTHOR]

The first edge illuminated SiGe phototransistor based on the available commercial SiGe/Si BiCMOS technology for a low‐cost detector or mixer in radio‐over‐fibre applications. Its technology and structure are described. Edge mapping of the phototransistor performances, so as to observe the fastest and the highest sensitive areas of the structure, is performed. The phototransistor exhibits a cutoff frequency of 890 MHz and low frequency responsivity of 0.45 A/W at 850 nm. This new SiGe/Si phototransistor structure provides a cutoff frequency double that of a top illuminated SiGe/Si phototransistor obtained using the same BiCMOS technology. [ABSTRACT FROM AUTHOR]

The first results of an integrated hybrid photo‐receiver based on a 850 nm two‐terminal (2T) silicon germanium (SiGe) heterojunction bipolar photo‐transistor (HPT) for low‐cost radio‐over‐fibre (RoF) applications is presented. A hybrid module was realised with two cascaded low‐noise amplifiers of 20 dB total gain and an SiGe 2T‐HPT exhibiting a −15 dB opto‐microwave gain at 5.15 GHz with a 1.6 GHz bandwidth. A 16% degradation of the error vector magnitude compared with back‐to‐back measurement for the transmission of a 2 GHz OFDM signal at 3 Gbit/s was measured based on the 60 GHz IEEE 802.15.3c standard transposed at the intermediate frequency (IF) of 5 GHz, according to an IF‐RoF distribution mode. [ABSTRACT FROM AUTHOR]