Small Cell Basestations (BTS) are a new type of BTS required by the increased mobile data load on cellular networks. They are intended to provide high voice and data capacity but need only cover a small cell area in areas where mobile demand is high, such as city downtowns, shopping malls, airports, campuses, and large offices.
Transmitted power is low so they can be integrated in small units which put high constraints on thermal dissipation and power consumption. However performance requirements are high because they need to provide the full capacity that the standard allows.
The following diagram shows how to build a highly integrated modem sub-system using a single OCT2224W. It interfaces with the radio sub-system through a direct parallel interface that supports MIMO or through the SRIO port via a CPRI bridge. The embedded CPU will handle the MAC processing as well as the SGMII backhaul interface.
The OCT2224W architecture has been designed to handle the software of all known cellular standards.
Modems are implemented mostly in software but use a few hardware accelerators that are highly programmable and can adapt to future cellular standards revisions and evolutions.
Octasic offers GSM-EDGE and WCDMA-HSPA Layer 1 Library in source code format, both optimized for the OCT2224W Opus2 DSP core. These libraries can be used as is to build a complete BTS can be combined with the system integrator's proprietary algorithms.
Octasic offers a complete set of development tools for the OCT2200 Series of devices. Opus Studio, an integrated development environment (IDE), provides the necessary tools for code editing, compiling, simulation, debugging, and profiling. Octasic also provides a real-time kernel and RTOS services upon which embedded applications can rapidly be developed.