Environment Division Multiple Access (EDMA): A Feasibility Study via Pinching Antennas

TL;DR

This work introduces environment-division multiple access (EDMA), a new multi-user technique that uses pinching antennas to dynamically reconfigure propagation environments and suppress interference without heavy signal processing. By partitioning the service area and blocking interfering LoS links, EDMA enables simultaneous, interference-aware access and yields a provable ergodic sum-rate gain over TDMA, with closed-form results in the two-user case and tractable optimization for antenna placement. The paper provides two low-complexity optimization algorithms—golden-section search for uplink and a successive convex approximation approach for downlink—to locate pinching antennas and demonstrates, via numerical results, substantial performance gains and practical viability. Overall, EDMA offers a promising, low-complexity mechanism to enhance multi-user throughput in millimeter-wave/THz environments by exploiting reconfigurable propagation environments rather than relying on conventional signal processing alone.

Abstract

This paper exploits the dynamic features of wireless propagation environments as the basis for a new multiple access technique, termed environment division multiple access (EDMA). In particular, with the proposed pinching-antenna-assisted EDMA, the multi-user propagation environment is intelligently reconfigured to improve signal strength at intended receivers and simultaneously suppress multiple-access interference, without requiring complex signal processing, e.g., precoding, beamforming, or multi-user detection. The key to creating a favorable propagation environment is to utilize the capability of pinching antennas to reconfigure line-of-sight (LoS) links, e.g., pinching antennas are placed at specific locations, such that interference links are blocked on purpose. Based on a straightforward choice of pinching-antenna locations, the ergodic sum-rate gain of EDMA over conventional multiple access and the probability that EDMA achieves a larger instantaneous sum rate than the considered benchmarking scheme are derived in closed form. The obtained analytical results demonstrate the significant potential of EDMA for supporting multi-user communications. Furthermore, pinching antenna location optimization is also investigated, since the locations of pinching antennas are critical for reconfiguring LoS links and large-scale path losses. Two low-complexity algorithms are developed for uplink and downlink transmission, respectively, and simulation results are provided to show their optimality in comparison to exhaustive searches.

Figures (9)

• Figure 1: Illustration of the considered multi-user EDMA system. The Internet of Things (IoT) application figure in Fig. \ref{['fig1a']} is based on an image generated by Google Gemini.
• Figure 2: Illustration of the accuracy of the approximated system model. The cases with and without taking into account interfering pinching antennas that are more than two segments away are shown. An uplink scenario with $M=5$ users is considered, $D_{\rm S}$ denotes the segment width, $D_{\rm W}=10$ m, $d=3$ m, $f_c=28$ GHz, $\phi=0.02$, and $D_{\rm L}=MD_{\rm S}$, and the noise power is $-90$ dBm. The figure focuses on the worst user, ${\rm U}_3$, which suffers the most interference.
• Figure 3: The uplink and downlink ergodic sum rates achieved by the proposed EDMA scheme, where the TDMA schemes assisted by conventional and pinching antennas are used as the benchmarking schemes, and $D_{\rm L} =4D_{\rm W}$.
• Figure 4: The ergodic sum-rate gain achieved by EDMA over pinching-antenna assisted TDMA, where the special case with $M=2$ is focused on. The approximation is based on \ref{['approx']}, and the shown analytical results are based on Lemma \ref{['lemma1']}.
• Figure 5: The probability of EDMA outperforming pinching-antenna assisted TDMA, $\mathbb{P} (\Delta_{\rm sum}\geq 0)$, where $M=2$, $y_m=0$, $1\leq m\leq M$, and the transmit power is $30$ dBm. The analytical results are based on Lemma \ref{['lemma3']}.

Theorems & Definitions (2)

• proof
• proof