Propsim C8 MIMO Extension. 4x4 MIMO Radio Channel Emulation

Transcription

1 Propsim C8 MIMO Extension 4x4 MIMO Radio Channel Emulation Propsim C8 provides a flexible platform for Multiple Input Multiple Output (MIMO) development and evaluation. With a maximum number of 16 independent fading channels the Propsim C8 MIMO Extension allows emulation of complex scenarios such as 4x4 MIMO within one device. More complex scenarios, for example multiuser MIMO scenarios, are supported by synchronising multiple units. Test case connections, correlative radio channel models and emulations are fast and easy to create with the Graphical User Interface. rcpsales@elektrobit.com / Internet: / 1 (9)

2 MIMO Technology New Aspects for Performance Testing MIMO technologies utilize the impairments within the various different propagation paths to gain additional system performance, either as extended coverage or as higher data rates. The MIMO gain is based on the non-correlative behaviour of independent transmission paths. In ideal conditions the parallel MIMO sub channels are uncorrelating but propagation measurements have proven that this is not always the case in real-world. It is recommended to test the performance of the system under non-ideal conditions with several different levels of correlation between the parallel MIMO sub channels. As the system gain is affected heavily by the correlation between channels it is necessary to be able to emulate the correlation in the channel models accurately but also repeat the same test cases with same correlation behaviour. This correlation accuracy and repeatability is crucial for any performance test environment of MIMO systems and essential in being able to discover the real performance of design under test. Propsim C8 Accurate MIMO Channel Emulator The accuracy of parameters such as phase error between paths and channels, amplitude accuracy between paths and channels, correlation between channel models on different channels and accuracy of the calculated correlation matrices are important as they create the base for MIMO-gain. The integrated Propsim C8 multichannel emulator design is based on the mentioned MIMO-emulation and -modelling fundamentals and therefore it provides the best features and performance to carry out accurate and repeatable MIMO development testing. It features also support for usage of one RFLO signal for all channels to minimise phase noise affects for correlation accuracy and build in AWGN and interference generation capabilities to enable users to test MIMO systems under controlled interference conditions. The new MIMO extension supports up to 4x4 MIMO configurations. It is designed on the existing Propsim C8 emulator platform enabling upgrade path for existing emulators and supporting upgrade path from basic 2 channel configurations up to full 4x4 when needed. Other optional features include different type of channel Figure 1. Generic MIMO Receiver rcpsales@elektrobit.com / Internet: / 2 (9)

3 modelling tools and number of paths/channel to enable application specific feature sets. Supports Any Wireless Technology MIMO systems are being investigated for various different wireless standards ranging from WLAN / Wi-Fi and WiMAX to WCDMA, TD-SCDMA and B3G systems. With Propsim C8 supporting operating frequencies up to 6GHz and bandwidths up to 100MHz, the performance gain from MIMO can be evaluated for any wireless technology. Propsim C8 has Analog and Digital Baseband interfaces enabling testing of MIMO algorithms already when developing the baseband e.g. chipsets. The new Propsim C8 with MIMO Extension provides a versatile platform that is easily configured by user for different Tx- and Rx-antenna MIMO configurations. This provides users with a flexible solution for any MIMO technology development with different type of Tx and Rx antenna setups. Propsim C8 provides versatile modelling tools for MIMO MIMO channel models are being developed for different standards including 3GPP, , and future 4G systems. Propsim C8 supports all known models already standardised or in pre-standardisation phase. The models under standardisation include 3GPP SCM and SMCE models for WCMDA-MIMO, n TGn models for WLAN MIMO and various proposal for WiMAX and 4G systems. The development and standardisation of the MIMO-models and modeling techniques is ongoing and new models are to be introduced. channel emulation platforms are designed to support any channel models and therefore the Propsim C8 emulator is future proof for new MIMO models. Figure 2 Modeling correlative channels in Propsim C8 with Spatial Channel Modeling (SCM) approach The Propsim C8 graphical user interface (GUI) allows users to create their own channel models with arbitrary complex correlations based on Tx and Rx antenna correlation matrices. This way the correlation between individual fading paths on different channels can be controlled accurately. This is also considered as the main stream in MIMO-modelling. The GUI-tool also supports Direction of Arrival (DoA) channel modeling for Antenna Array Systems (AAS). To enable modeling flexibility in Propsim C8 users can import channel models from other modeling sources e.g. MatLab. This provides user the possibility to model all fading effects e.g. Doppler spectra, amplitude distribution and correlation matrices freely. Propsim C8 offers as an option an easy to use channel modeling tool for generating n TGn standard compliant channel models. The emulator unit also includes wide variety of pre-defined standard channel models. rcpsales@elektrobit.com / Internet: / 3 (9)

4 Supporting Propsim C8 Options Propsim C8 Internal Local Oscillator Figure 3 Modeling correlative channels in Propsim C8 with Kroenecker product approach MIMO Setup Examples Internal Local Oscillator provides ease of use to Propsim C8 in multichannel emulation as the emulator sets the correct local oscillator frequency automatically based on frequency setting. When using a unit equipped with internal LO no external RF signal generators are needed for up- and down conversion. Up to 4 sources can be installed in one emulator. When using same frequency on all channels one local source is used to generate the RFLO for all channels. This is essential in MIMO and Smart Antenna testing to minimise the effects of phase noise. Appendix A shows some examples of the flexibility and versatility of the Propsim C8 MIMO Extension in the form of various available MIMO configurations. All these different connection versions are SW-controlled via the Propsim C8 GUI. Propsim C8 TGn Channel Modeling Tool The TGn tool generates IEEE n based MIMO channel models based on multiple parameters, such as: TGn scenario, link direction, line of sight condition, distance between Tx and Rx elements, frequency band, number of Tx and Rx antennas and Tx and Rx ULA antenna element separation. Based on these parameters the TGn tool creates the necessary correlating radio channel models for the emulation. Together with the Propsim C8 4x4 MIMO Extension option it creates an accurate, realistic and standards compliant performance evaluation and testing solution for n based MIMO solutions. More information is available in Propsim C8 TGn Channel Modeling Tool option overview. rcpsales@elektrobit.com / Internet: / 4 (9)

5 features rich variety of setting modes to make testing based on standards like 3GPP straightforward and easy. More information is available in Propsim C8 Internal Interference Generator option overview. Figure 4. Propsim TGn Tool Propsim C8 Internal Interference Generator Internal Interference generator provides independent interference source for each channel. Each generator can be fitted with following interference types: AWGN, CW, GMSK, 8-PSK, WCDMA DL and WCDMA UL. Interference generator is designed to be upgradeable with other interference types. Internal interference generator option allows user to create the typically needed interfering signals without need of multiple external devices. Signal generation and C/I measurement is implemented digitally to provide best possible emulation accuracy. Control of C/I or S/N / Internet: / 5 (9)

6 Appendix A. 4x4 MIMO Downlink / Internet: / 6 (9)

7 4x2 MIMO Full Duplex / Internet: / 7 (9)

8 2x2 MIMO Multi-User / Internet: / 8 (9)

9 s goal is to become a world leading embedded software and hardware provider in selected areas in wireless and automotive environments. Besides R&D services, s product portfolio covers 3G smartphone platform, IP radio base station modules, in-car software, and testing, material handling and process automation equipment for the electronics industry and teleoperators. rcpsales@elektrobit.com / Internet: / 9 (9)