Segmented silicon MZM for PAM-8 transmissions at 114 Gb/s with binary signaling

Abstract

We experimentally demonstrate PAM-8 generation from binary electrical signals driving a silicon multi-electrode Mach-Zehnder modulator acting as an optical digital-to-analog converter. Measured BER in back-to-back configuration is used to evaluate signal quality. We demonstrate 38 GBd PAM-8 transmission below the forward error correction (FEC) threshold using minimum mean square error (MMSE) equalization. The results show that modulators with segmented phase shifters can be advantageously used to eliminate the need for high bandwidth electronic digital-to-analog converters in the generation of multilevel signals. These modulators, that can be designed and fabricated with standard CMOS compatible tools and processes, are of high interest for short range high-speed data links.

Low-power DAC-less PAM-4 transmitter using a cascaded microring modulator

“…Nonetheless, one must consider that this dramatic reduction in power consumption, at the transmitter side, results in a trade-off, the degradation of the performances at the receiver side. For instance, compared with [18], our results show around 8 dB of power penalty at 20 GBaud for a BER of 10 −3 .…”

“…Accordingly, the total power consumption of the modulator here presented is in the vicinity of 100 fJ/bit for data rates of 50-60 Gb/s, which is quite low considering that this power budget includes the DAC. In fact, it is advantageously comparable to a similar demonstration using MZI [18], in which the use of segmented electrodes allows the generation of a PAM signal, but at a much higher power consumption, i.e. 7.7 pJ/bit.…”

Experimental Study of 1.55- $\mu$ m EML-Based Optical IM/DD PAM-4/8 Short Reach Systems

“…Advanced modulations formats are extensively studied for short reach applications: (1) pulse amplitude modulation (PAM) [6]- [16], (2) carrierless amplitude phase (CAP) modulation [17], or (3) discrete multi-tone (DMT) [13], [18]. Such formats allow for more efficient bandwidth utilization at the cost of complex digital signal processing (DSP), which also may result in a higher costs and power consumption.…”

“…These demonstrations usually require long digital filters resulting in complicated implementations. Hence, consensus seems to evolve towards 4PAM [6]- [16] and on-off keying (OOK) [14], [19]- [23] as it saves complexity on the transmitter side. Limiting amplifiers and electrical multiplexers technologies up to 120 Gbps have already matured into products.…”

Highly linear W-band receiver front-end based on higher-order optical sideband processing

“…1. An RF signal at the W-band is first down-converted to an IF because of the performance and price constraints of high-frequency modulators [24] . Next, the IF signal is modulated onto a light signal, and then is processed with an optical signal processor to suppress the IMD3.…”