Broadcast services for wireless local area networks (WLANs) are being standardized in the IEEE 802.11 task group bc. Envisaging the upcoming coexistence of broadcast access points (APs) with densely-deployed legacy APs, this paper addresses a learning-based spatial reuse with only partial receiver-awareness. This partial awareness means that the broadcast APs can leverage few acknowledgment frames (ACKs) from recipient stations (STAs). This is in view of the specific concerns of broadcast communications. In broadcast communications for a very large number of STAs, ACK implosions occur unless some STAs are stopped from responding with ACKs. Given this, the main contribution of this paper is to demonstrate the feasibility to improve the robustness of learning-based spatial reuse to hidden interferers only with the partial receiver-awareness while discarding any re-training of broadcast APs. The core idea is to leverage robust adversarial reinforcement learning (RARL), where before a hidden interferer is installed, a broadcast AP learns a rate adaptation policy in a competition with a proxy interferer that provides jamming signals intelligently. Therein, the recipient STAs experience interference and the partial STAs provide a feedback overestimating the effect of interference, allowing the broadcast AP to select a data rate to avoid frame losses in a broad range of recipient STAs. Simulations demonstrate the suppression of the throughput degradation under a sudden installation of a hidden interferer, indicating the feasibility of acquiring robustness to the hidden interferer.

In this paper, the packet error rate (PER) of IEEE 802.15.4 under the interference of a saturated IEEE 802.11b network is evaluated using an analytic model when IEEE 802.15.4 and IEEE 802.11b coexist. The PER is obtained from the bit error rate (BER) and the collision time, where the BER is obtained from the signal-to-interference-plus-noise ratio. The analytic results are validated using simulations.

Over the past ten years, the demand for low-cost, low-power, and small form-factor portable wireless devices has led to the integration of RF transceivers on the same silicon as digital processors to form wireless systems-on-a-chip. This paper describes the challenges in designing CMOS systems-on-a-chip for wireless communications. RF transceiver building blocks for signal amplification, frequency translation, and frequency selectivity are examined with special emphasis on low noise amplifiers, power amplifiers, mixers, and frequency synthesizers. System-on-a-chip integration issues such as leakage currents of digital logic, calibration techniques, and noise coupling are also discussed.

In this paper, the performance of IEEE 802.11b WLAN under the interference of IEEE 802.15.4 WPAN is analyzed. An analytic model for the coexistence of IEEE 802.15.4 and IEEE 802.11b is presented. Packet error rate, average transmission time, and throughput are evaluated.

Wireless networks have been rapidly integrated with the wired Internet and considered as the most popular MAC technology for Ad Hoc mobile communications. In WLAN technologies, IEEE 802.11b WLAN is the most widespread wireless network today. The IEEE 802.11b WLAN supports multiple transmission rates and the rate is chosen in an adaptive manner by an auto rate control algorithm. This auto rate control algorithm deeply affects the total system performance of the IEEE 802.11b WLAN. In this paper, we examine the WLAN performance with regard to the auto rate control algorithm, especially the ARF scheme, which is the most popular auto rate control algorithm in 802.11b based WLAN products. The experimental results indicate that the ARF scheme works well in the face of signal noise due to node location. However, the ARF scheme severely degrades system performance when multiple nodes contend to obtain the wireless channel and the packet is lost due to signal collision.

A new error correction block based Hybrid ARQ protocol, in which PHY layer packets are composed of multiple error correction blocks, is devised together with a retransmission control scheme constructed on the basis of these error correction blocks. This protocol is designed dedicatedly for mobile AV stations to provide the high quality digital video transmission through a radio channel. To analyze the performance of this protocol, the frame loss rate vs. the uncorrectable error probability is simulated, in comparison with the ordinary packet based retransmission control. A wireless video transmission system using IEEE802.11b PHY is also described, which has been developed with the use of a Medium Access Control (MAC) LSI to perform the proposed protocol.