Interference management in LTE‐based HetNets: a practical approach

Abstract

Interference is a major obstacle in radio communications, especially when opportunistic frequency reuse is an inherent requirement for maximizing spectral efficiency in heterogeneous networks. A typical example is encountered in cellular communications where macro cell-edge users receive interference from small cell transmissions that use the same radio frequency band. Innovating interference management algorithms are employed towards this end, which due to their interdependencies with numerous parameters of the target operating scenario and various low-level implementation aspects, need to be prototyped in real-time signal processing platforms in order to be credibly verified. In this paper, we present the development and experimental validation of a macro/femto cell coexistence scenario in close to reallife conditions. The inclusion of an agile interference management scheme increased the signal processing complexity at the physical layer. This overhead was appropriately addressed by engaging advanced parallel processing techniques, optimizations of the arithmetic operations and intelligent reuse of logic and memory resources in the FPGA-based baseband processing architecture.

Measuring the performance of a distributed interference management scheme in a LTE-based HetNet deployment

“…The defined threshold-value aims at ensuring a baseline macro UE performance: the probability that the uncoded biterror-rate (BER) is below 10 −2 must be above 0.8 [1].…”

“…USING THE GEDOMIS TESTBED The PHY-layer of the two BSs and UEs of the target interference management scenario was prototyped using the FPGA-based development boards of the GEDOMIS testbed [1]. The baseband boards also include high-end multichannel signal conversion circuitry.…”

“…The baseband building blocks of all the entities were implemented in field programmable gate array (FPGA) devices using a custom hardware description language (HDL) design approach [1]. The real-time FPGA implementation encapsulated advanced parallel processing techniques and a hardware-aware optimization of the arithmetic operations.…”

Kernel canonical correlation analysis for robust cooperative spectrum sensing in cognitive radio networks

“…A typical scenario of current interest where the presence of interference can impair spectrum sensing can be found in heterogeneous networks (HetNets), where a macrocell‐edge user may experience interference from small cell transmissions using the same radio frequency (RF) band. This scenario is considered in , where an interference‐mitigation scheme close to macrocell/femtocell real‐life scenario is experimentally evaluated. Another recent work that takes into account interference in the CR context is , where, with the assistance of geolocation information, a sensing scheme that decomposes the received power into the primary signal power, secondary signal power (treated here as interference) and the device noise power is proposed.…”

Energy footprint reduction in 5G reconfigurable hotspots via function partitioning and bandwidth adaptation

“…• HWA: The LTE-based DL physical-layer (L1) developed at CTTC targeting field programmable gate array (FPGA) devices [11].…”