A Channel Sounder for Massive MIMO and MmWave Channels

Both massive multiple-input multiple-output (MIMO) technology and use of frequencies in the range 24100 GHz are considered essential for upcoming 5G systems. Measurements of the new type of channels are needed, but this is challenging due to the large number of channels in massive MIMO and the short wavelength in the 24100 GHz channels (so-called mmWave channels). This article describes a sounder system capable of measurements in both types of channels. While the same sounder system supports simultaneous massive MIMO and mmWave channels, the number of channels in each band and in total is in practice limited. For massive MIMO in the 3006000 MHz band alone, arrays with up to 128 receiver (Rx) elements are possible, receiving from 16 independent mobile transmitter (Tx) antennas, where all channels are measured within 1.3 ms and in a 200 MHz bandwidth. To the authors' knowledge, this is the first sounding system with this number of channels and a speed necessary for measuring the dynamic channels in typical application scenarios. For mmWave channels, the sounder operates in the range 1840 GHz. For these bands up to 2 Tx elements and 16 Rx elements can be measured. In addition, the article describes some measurements in both a massive MIMO setup in an indoor sports arena and an mmWave setup with a

[1]  Xiongwen Zhao,et al.  3D MIMO for 5G NR: Several Observations from 32 to Massive 256 Antennas Based on Channel Measurement , 2018, IEEE Communications Magazine.

[2]  Sana Salous,et al.  Wideband MIMO Channel Sounder for Radio Measurements in the 60 GHz Band , 2016, IEEE Transactions on Wireless Communications.

[3]  D. Cox.  Delay Doppler characteristics of multipath propagation at 910 MHz in a suburban mobile radio environment , 1972 .

[4]  Andreas F. Molisch,et al.  Millimeter-Wave Channel Measurements and Analysis for Statistical Spatial Channel Model in In-Building and Urban Environments at 28 GHz , 2017, IEEE Transactions on Wireless Communications.

[5]  Pertti Vainikainen,et al.  Characterization system for radio channel of adaptive array antennas , 1997, Proceedings of 8th International Symposium on Personal, Indoor and Mobile Radio Communications - PIMRC '97.

[6]  Yang Hao,et al.  Experimental Characterization and Statistical Analysis of the Pseudo-Dynamic Ultrawideband On-Body Radio Channel , 2011, IEEE Antennas and Wireless Propagation Letters.

[7]  Jun-ichi Takada,et al.  Novel Scalable MIMO Channel Sounding Technique and Measurement Accuracy Evaluation With Transceiver Impairments , 2012, IEEE Transactions on Instrumentation and Measurement.

[8]  Kate A. Remley,et al.  A Radio Channel Sounder for Mobile Millimeter-Wave Communications: System Implementation and Measurement Assessment , 2016, IEEE Transactions on Microwave Theory and Techniques.

[9]  Theodore S. Rappaport,et al.  A Flexible Millimeter-Wave Channel Sounder With Absolute Timing , 2017, IEEE Journal on Selected Areas in Communications.

[10]  Jesper Ødum Nielsen,et al.  Measured 21.5 GHz Indoor Channels With User-Held Handset Antenna Array , 2017, IEEE Transactions on Antennas and Propagation.

[11]  Jianhua Zhang,et al.  3-D MIMO: How Much Does It Meet Our Expectations Observed From Channel Measurements? , 2017, IEEE Journal on Selected Areas in Communications.

[12]  Michael A. Jensen,et al.  24 GHz indoor MIMO channel measurements , 2015, 2015 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting.

[13]  Fredrik Tufvesson,et al.  Massive MIMO Performance Evaluation Based on Measured Propagation Data , 2014, IEEE Transactions on Wireless Communications.