Using DSP-based effective wireless ethernet accumulation of networks

Abstract

Mobile fronthaul is an important segment of the network that bridges wireless baseband and remote radio units to support network access to cloud radio. We review recent developments in the use of frequency-division multiplexing to achieve highly bandwidth-efficient, low latency mobile fronthauling. Digital signal processing (DSP) techniques are described for frequency domain windowing, adjacent channel leakage ratio reduction, channel aggregation and deaggregation and synchronous transmission of both the control words (CWs) used for control and management, wireless signal I / Q waveforms. In this experiment, we reveal the transmission of 48 20-MHz LTE signals with a common public radio interface (CPRI) identical data rate of 59 Gb / s, attained a short round-trip DSP latency of < 2 μs, and a small mean error-vector magnitude (EVM) of ∼ 2.5% behind fiber transmission. In a follow-up experiment, together with CPRI-compliant CWs, we further demonstrate the transmission of 32 20-MHz LTE signals, corresponding to a CPRI-equivalent data rate of 39.32 Gb / s, in a single optical wavelength channel which requires an RF bandwidth of only 1.6 GHz. The CWs are recovered without error after transmission over 5 km of standard single-mode fiber, while the LTE signals are recovered with an EVM of<3 per cent. It is also discussed how to apply this technique to future 5 G wireless networks with massive multiple-input multiple outputs. This efficient mobile fronthaul technique may find promising applications for providing ultrabroadband access services in future integrated fiber / wireless access networks.