CNS Core: Small: attaining Multi-Terabit/sec Wireless Data Rates

1. Distance measurements

Measurement Description: This measurement replicate a 2x2 linear MIMO setup. Each data set has 4 files: Tx1Rx1, Tx1Rx2, Tx2Rx1 and Tx2Rx2. The distance between the two antenna in the direction of propagation (R) can be selected with values from 4 inches to 32 inches. The spacing between two antenna element (D) is calculated so that R=18in data set is measured with optimal spacing. This spacing is kept the same between different distances (R).

Measurement Description: This measurement replicate a 4x4 linear MIMO setup. Each data set has 16 files: Tx1Rx1, Tx1Rx2, Tx1Rx3, Tx1Rx4, Tx2Rx1, Tx2Rx2, Tx2Rx3, Tx2Rx4, Tx3Rx1, Tx3Rx2, Tx3Rx3, Tx3Rx4, Tx4Rx1, Tx4Rx2, Tx4Rx3, and Tx4Rx4. The distance between the two antenna in the direction of propagation (R) can be selected with values from 4 inches to 32 inches. The spacing between two antenna element (D) is calculated so that R=18in data set is measured with optimal spacing. This spacing is kept the same between different distances (R).

2. Offset measurements

Measurement Description: This measurement replicate a 2x2 linear MIMO setup with some offset. Each data set has 8 files: Tx1Rx1, Tx1Rx2, Tx1Rx3, Tx1Rx4, Tx2Rx1, Tx2Rx2, Tx2Rx3 and Tx2Rx4. The distance between the two antenna in the direction of propagation (R) is set to 6 inches or 18 inches. The spacing between two antenna elements (D) is calculated from R accordingly for the optimal spacing. This spacing is also used as the offset distance.

3. Ground reflection

Measurement Description: This measurement aims to study the effect of ground reflection from the optic table. A wet towel is placed on top of the table to eliminate any ground reflection. This measurement condition is compared to the case where we don't use the towel. The five measured distances are 14, 16, 18, 20, and 22 inches. Each data set has 10 files corresponding to the five distances and the two cases with and without the wet towel.

4. Non Line of Sight: Flat surfaces reflection measurements

Measurement Description: This measurement is our first attempt to characterize non-line-of-sight propagation. The signal is reflected off a metallic surface at different angles of incidence. The wet towel on the optic table is to make sure that there are no additional reflections. There are two types of movements: 1) Both Tx and Rx are moving and 2) Tx at a constant distance and only Rx moving.

5. Non Line of Sight: Multipath reflection measurements

Measurement Description: The setup of these measurements are similarly to measurement 4 in which the signal is reflected on surfaces. The differences are that the reflection surfaces are chosen such multipath occurs. Measurement is done strictly on a 2x2 configuration so that capacity can be analyzed to find better suit reflection surfaces for THz communication. From left to right are reflective surfaces created from nails, pins, and zigzag blades. There are 5 types of surfaces created: type 1 (3 rows of nails), type 2 (3 rows of pins), type 3 (5 rows of pins), type 4 (horizontal zigzag blades), and type 5 (vertical zigzag blades).

6. Relective Line of Sight: Controlled multipath reflection measurements

Measurement Description: The setup of these measurements are similarly to measurement set up 5 in which the signal is reflected on surfaces that can provide multipaths. The diagram on the left shows 3 different relective structures with 3 rows of metal strips at different spacing. The use of individual strips allows us to change the density of reflective elements thus enabling the ability to control the amount of diffusion that happens as the wave travels through the structure. Measurement is done strictly on a 2x2 configuration so that capacity can be analyzed to find better suit reflection surfaces for THz communication. The middle and right pictures demonstrate the top and front view.

Measurement Description: Measurement of single strip is to find working principle of the structures above in attempt to design better passive reflectors for MIMO channel. Measurements are done at different positions of the frame both X and Y axis. X-axis is along the rail while Y coordinate is controlled by a positioner placed on top of the rail. Measurement is done only on a 1x1 configuration (TX1RX1).