UWB over fiber transmission to multiple radio access units using all-optical signal processing

A full‐duplex ultra‐wideband over multimode fiber link for internet of things based smart home applications

“…The UWB band starting from 3.1‐10.6 GHz is very wide and various other wireless signals can co‐exist with UWB signals leading to unavoidable interference. The interference between UWB and co‐existing wireless services can be mitigated by following certain rules as regulated by FCC in year 2002 on UWB called the FCC mask 7,8 . The salient features of this FCC legislation over UWB are summarized as follows: 9 The UWB unlicensed transmission should be in 3.1‐10.6 GHz band. The power spectral density should be less than ‐41.3 dB m /MHz. Fractional bandwidth of UWB should be more than 20% of the carrier frequency or 10 dB bandwidth of at least 500 MHz. …”

“…The employment of UWB has also been regulated in 22‐29 GHz band reserved for vehicular radar applications while the above‐mentioned band is used for indoor UWB wireless broadband networks. For both the bands, the power spectral density should not exceed ‐41.3 dB m /MHz 8,9 . Recently, the use of UWB communication has been extended in millimeter wave band worldwide.…”

“…Owing to simplicity and ease of generation, UWB mono‐cycle pulses are frequently used in UWB communication. The intention behind using these specific shaped pulses for data transmission in UWB communication instead of simple Gaussian pulses is to achieve good bit‐error‐rate (BER) performance and reduced multi‐path effects associated with aforementioned shapes 8 . As each pulse type is characterized by shape, polarity, position, amplitude, and width, different modulation formats for UWB may be implemented using these characteristics such on‐off keying (OOK), pulse polarity modulation (PPM), and pulse shape modulation (PSM), as shown in Figure 1.…”

“…Bidirectional UWB signal transmission of 3.125 Gbps in the downlink and 2 Gbps in the uplink directions over a single fiber is presented in References 13. Generation of UWB mono‐cycle pulses based on optical delay line technique for the transmission of 5 × 1.25 Gbps data from control unit to RAUs has been demonstrated in Reference 8. A fiber nonlinearity based UWB pulse generation at 12.5 Gbps and 950 Mbps is demonstrated by phase modulation in a nonlinear medium followed by intensity modulation using a shaping filter 14,15 .…”

Millimeter‐wave signal generation and transmission to multiple radio access units by employing nonlinearity of the optical link

“…A polarization multiplexing‐based RoF architecture has been proposed by Mehmood et al, where optical mm‐wave carriers are transmitted to a ring of four RAUs. Aziz et al proposed a broadcast ultrawideband over fiber architecture, where a single laser source is utilized to transmit pulsed optical signals to five different RAUs arranged in a star topology.…”