376
9 Analog Optical Fiber Channels
links using a Mach–Zehnder interferometer-based modulator are able to maintain a
112-dB · Hz
2/3 SFDR out to about 17 GHz.
Drill Problem 9.4 Consider an analog link that has equal signal powers at
frequencies 3.000 and 3.001 GHz. Show that (a) second-order harmonics occur
at 6.000 and 6.002 GHz; (b) second-order intermodulation spurs occur at 0.001
and 6.001 GHz; and (c) third-order intermodulation spurs occur at 2.999 and
3.002 GHz.
9.5 Radio-Over-Fiber Links
The transition in the use of wireless devices from pure voice communications to a
wide selection of broadband services created much interest in developing radio-overfiber (ROF) links [2–9]. The convergence of optical and wireless access networks is
driven by the need to have seamless connectivity between an access network and both
stationary and fast-moving mobile users at data rates of at least 2.5 Gb/s. The implementations of ROF links include the interconnection of antenna base stations with a
central controlling office in a wireless access network, access to wireless services for
indoor environments (e.g., large office buildings, airport departure lounges, hospitals, conference centers, hospitals, and hotel rooms), and connections to personal
area networks in homes. Services of interest to mobile users include broadband
Internet access, fast peer-to-peer file transfers, high-definition video, and online
multiparty gaming. Depending on the network type, the optical links can use singlemode fibers, 50- or 62.5-µm core-diameter multimode glass fibers, or large-core
multimode polymer optical fibers.
One application of radio-over-fiber technology is in broadband wireless access
networks for interconnecting antenna base stations (BSs) with the central controlling
office. Figure 9.7 shows the basic network architecture for such a scheme. Here a
number of antenna base stations provide wireless connectivity to subscribers by
means of millimeter-wave frequencies. Subscribers are located up to 1 km from a
local base station. The transmission range around a BS is called a microcell (diameter
less than 1 km) or a picocell or hotspot (radii ranging from 5 to 50 m). The BSs
are connected to a microcell control station (CS) in the central office, which is
responsible for functions such as RF modulation and demodulation, channel control,
and switching and routing of customer calls.
9 Analog Optical Fiber Channels
links using a Mach–Zehnder interferometer-based modulator are able to maintain a
112-dB · Hz
2/3 SFDR out to about 17 GHz.
Drill Problem 9.4 Consider an analog link that has equal signal powers at
frequencies 3.000 and 3.001 GHz. Show that (a) second-order harmonics occur
at 6.000 and 6.002 GHz; (b) second-order intermodulation spurs occur at 0.001
and 6.001 GHz; and (c) third-order intermodulation spurs occur at 2.999 and
3.002 GHz.
9.5 Radio-Over-Fiber Links
The transition in the use of wireless devices from pure voice communications to a
wide selection of broadband services created much interest in developing radio-overfiber (ROF) links [2–9]. The convergence of optical and wireless access networks is
driven by the need to have seamless connectivity between an access network and both
stationary and fast-moving mobile users at data rates of at least 2.5 Gb/s. The implementations of ROF links include the interconnection of antenna base stations with a
central controlling office in a wireless access network, access to wireless services for
indoor environments (e.g., large office buildings, airport departure lounges, hospitals, conference centers, hospitals, and hotel rooms), and connections to personal
area networks in homes. Services of interest to mobile users include broadband
Internet access, fast peer-to-peer file transfers, high-definition video, and online
multiparty gaming. Depending on the network type, the optical links can use singlemode fibers, 50- or 62.5-µm core-diameter multimode glass fibers, or large-core
multimode polymer optical fibers.
One application of radio-over-fiber technology is in broadband wireless access
networks for interconnecting antenna base stations (BSs) with the central controlling
office. Figure 9.7 shows the basic network architecture for such a scheme. Here a
number of antenna base stations provide wireless connectivity to subscribers by
means of millimeter-wave frequencies. Subscribers are located up to 1 km from a
local base station. The transmission range around a BS is called a microcell (diameter
less than 1 km) or a picocell or hotspot (radii ranging from 5 to 50 m). The BSs
are connected to a microcell control station (CS) in the central office, which is
responsible for functions such as RF modulation and demodulation, channel control,
and switching and routing of customer calls.