High Efficiency, Good phase linearity 0.18 µm CMOS Power Amplifier for MBAN-UWB Applications

This paper presents the design of 3.1-10.6 GHz class AB power amplifier (PA) suitable for medical body area network (MBAN) Ultra-Wide Band (UWB) applications in TSMC 0.18 µm technology. An optimization technique to simultaneously maximize power added efficiency(PAE) and minimize group delay variation is employed. Source and Load-pull contours are used to design inter and output stage matching circuits. The post-layout simulation results indicated that the designed PA has a maximum PAE of 32 % and an output 1-dB compression of 11 dBm at 4 GHz. In addition, a small group delay variation of ± 50 ps was realized over the whole required frequency band . Moreover, the proposed PA has small signal power gain (S21) of 12.5 dB with ripple less than 1.5 dB over the frequency range between 3.1 GHz to 10.6 GHz, while consuming 36 mW.

On Ultra-Reliable Low Latency Multipath TCP For Connected Autonomous Vehicles

Connected Autonomous Vehicles (CAVs) are Not-So-Futuristic. CAVs will be highly dynamic by intelligently exploiting multipath communication over several radio technologies, such as high-speed WiFi and 5G and beyond networks. Yet, the likelihood of data communication loss can be very high and/, or packets arrive at the destination not in correct working order due to erratic and mixed time-varying wireless links. Furthermore, the vehicular data traffic is susceptible to loss and delay variation,which recommends the need to investigate new multipath TCP(MPTCP) protocols for ultra-reliable low latency communication(URLLC) over such heterogeneous networks while reassuring CAVs’ needs. We undertake the challenge by jointly considering network coding and balanced linked adaptation for performing coupled congestion control across multiple wireless paths.Consequently, the proposed low delay MPTCP framework for connecting autonomous vehicles is efficient and intelligent by design. We conduct a rigorous convergence analysis of the MPTCP design framework. In summation, we provide a detailed mathematical study and demonstrate that the latency penalty for the URLLC-MPTCP developed over these networks becomes negligible when considering the possible benefits that multiple network convergence could offer. Our extensive emulation results demonstrate all these lucrative features of URLLC-MPTCP.

On Ultra-Reliable Low Latency Multipath TCP For Connected Autonomous Vehicles

Connected Autonomous Vehicles (CAVs) are Not-So-Futuristic. CAVs will be highly dynamic by intelligently exploiting multipath communication over several radio technologies, such as high-speed WiFi and 5G and beyond networks. Yet, the likelihood of data communication loss can be very high and/, or packets arrive at the destination not in correct working order due to erratic and mixed time-varying wireless links. Furthermore, the vehicular data traffic is susceptible to loss and delay variation,which recommends the need to investigate new multipath TCP(MPTCP) protocols for ultra-reliable low latency communication(URLLC) over such heterogeneous networks while reassuring CAVs’ needs. We undertake the challenge by jointly considering network coding and balanced linked adaptation for performing coupled congestion control across multiple wireless paths.Consequently, the proposed low delay MPTCP framework for connecting autonomous vehicles is efficient and intelligent by design. We conduct a rigorous convergence analysis of the MPTCP design framework. In summation, we provide a detailed mathematical study and demonstrate that the latency penalty for the URLLC-MPTCP developed over these networks becomes negligible when considering the possible benefits that multiple network convergence could offer. Our extensive emulation results demonstrate all these lucrative features of URLLC-MPTCP.

Practical cross-layer testing of HARQ-induced delay variation on IP/RTP QoS and VoLTE QoE

As the PHY/MAC-layer IR-HARQ and RLC-layer ARQ error recovery procedures, adopted in LTE, may impose additional delay when their code-block retransmissions occur, the arising question is whether these significantly contribute to IP and consequently RTP packet delays, and finally degrade the overall application-layer end-to-end QoE, especially when voice is transmitted over LTE? With this regard, we propose and demonstrate a VoLTE QoS and QoE test procedure based on PHY/MAC/RLC/IP/TCP-UDP/RTP cross-layer protocol analysis and perceptual speech quality QoE measurements. We identified monotonic relationship between the paired observations: QoE and HARQ RTT, i.e. between the PESQ voice quality rating and the IP/RTP packet latency, for given BLER of the received MAC/RLC code-blocks. Specifically, we found out that, for the HARQ RTT value of about 8 ms, only up to 2 HARQ retransmissions (and consequently no RLC-ARQ one) is appropriate during any voice packet, otherwise delay accumulation might not be accordingly “smoothed out” by jitter/playback buffers along the propagation path.

Checking the Accuracy of Siitperf

Siitperf is the world’s first free software RFC 8219 compliant SIIT (Stateless IP/ICMP Translation, also called as Stateless NAT64) tester, which implements throughput, frame loss rate, latency and packet delay variation tests. In this paper, we show that the reliability of its results mainly depends on the accuracy of the timing of its frame sender algorithm. We also investigate the effect of Ethernet flow control on the measurement results. Siitperf is calibrated by the comparison of its results with that of a commercial network performance tester, when both of them are used for determining the throughput of the IPv4 routing of the Linux kernel.