  This paper presents a modern method for implementing burst modems in GNU
Radio. Since burst modems are widely used for multi-user channel access and
sharing in non-broadcast radio systems, this capability is critical to the
development of numerous waveforms in GNU Radio. We focus on making such systems
easy to develop and adapt to wide classes of modems and computationally
efficient at runtime. We use the GNU Radio Event Stream scheduler to
demonstrate concise implementations of burst PSK and FSK modems in GNU Radio
and compare this with alternate approaches which have been attempted in GNU
Radio.
