Radio Channel Measurements With Relay Link at 780 MHz in an Outdoor to Indoor Propagation Environment

Essi SuikkanenCentre for Wireless CommunicationsUniversity of OuluUniversity of Oulu

Outline

Motivation for the MeasurementsM tMeasurements

Settings, antennas, location

Post-processing of the Measurement Datap gPreliminary Results

Route 4BS t R lBS to RelayAll Routes Combined

4.12.2008 CWC | Centre For Wireless Communications 2

Motivation for the Measurements

Provide measurement data for the WINNER+ project to extend WINNER and IMT-A channel models down to 700-extend WINNER and IMT-A channel models down to 700-800 MHz.To get actual measurement data of a scenario where relay assisted transmission is used.

How much benefit can be gained from the use of a relay?Combat shadowing and path lossg pPotential to extend coverage and increase spectral efficiency

Measurements

Measurement settings:

Center frequency 780 MHz

Transmit power +25 dBmTransmit power +25 dBm

Bandwidth 50 MHz

Chi t 25 MChip rate 25 Mcps

Sampling frequency 50 MHz

Code length 4095 chips

Number of Tx antenna elements 6

Number of Rx antenna elements 6

4.12.2008 CWC | Centre For Wireless Communications 4

Measurements

Used antennas:

Antenna designation Discone

00 /Frequency / Bandwidth

700 MHz / 200 MHz

Radiation±180° Azimuth

Radiation90° Elevation

Gain ~ 3 dB

Antenna typeUniform circular array, 6 discone elements

Polarization Vertical

Measurements

Routes for measurements with mobilityBS-MS and relay-MS measurementsBS MS and relay MS measurements

Figures 1 and 2 show measured routes (pink lines), base station location (light blue dot) and relay location (green dot). The direction of the first antenna element is marked with red The direction of the first antenna element is marked with red arrow. The location of the relay is not shown in Figure 2 but it is the same as in the Figure 1.The height of the BS was at 23 metres and the height of the relay was 14 metres. Height of the MS antenna was 1.5 metres.

Measurements

Figure 2: Route 5 and two spotFigure 1: Routes 1-4.

Figure 2: Route 5 and two spot measurements.

Measurements

“Routes” for static measurementsBS relay measurementsBS-relay measurements

Figure 3 depicts the locations of the relays (green dots) and the base station (light blue dot). The direction of the first antenna element is marked with red arrowelement is marked with red arrow.Height of the BS was 23 metres and the height of the relay was 6-14 metres.

Measurements

59 m

42 m

Figure 3: Location of the base station and the relays.y

Measurements

Relay 1 Relay 4

Figure 4: View from the BS antenna to the lifter where the relay R1 was located. Also the location of the R4 is shown.

Measurements

BS

Figure 5: View from the relay antenna to the BS antenna.

Post-processing and Analysisp g y

For post-processing and analysis we use Matlab and ISIS The ISIS (Initialization and Search Improved SAGE) is Matlab The ISIS (Initialization and Search Improved SAGE) is Matlab based super-resolution option for post-processing and it provides multi-dimensional estimates of the wave parameters. It is based on the SAGE (Space-Alternating Generalized It is based on the SAGE (Space-Alternating Generalized Expectation-Maximization) maximum likelihood algorithm.

From the static measurements (BS-relay) the first 100 l f th t d t l dcycles of the measurement data are analyzed.

From the measurements where the MS was moving, the whole route is analyzed.yNoise threshold was set to 20 dB below the strongest tap for all measured impulse responses.

Preliminary Results – Route 4y

Preliminary results for route 4In the map below are shown the distances between the BS In the map below are shown the distances between the BS, relay and MS.

42-50 m

59 m

67-41 m

The beginning of route 4

Preliminary Results – Route 4y

1

- The walls in the beginning of the route are glass.

0 7

0.8

0.9

Mean: 25.57 ns

Std: 11.09 ns

bsci

ssa

- Obstructed LOS from the relay to the MS.

NLOS from the BS to0.5

0.6

0.7

Mean: 89.39 ns

Std: 37.23 ns

MS

del

ay <

Ab

- NLOS from the BS to the MS.

0.3

0.4

babi

lity

of R

M

0.1

0.2Pro

b

BS to MSR1 to MS

0 20 40 60 80 100 120 140 1600

RMS delay [ns]

Figure 6. Cdfs of RMS delay spread for route 4.

Preliminary Results – Route 4y

105

- Approximately 20 dB difference.

95

100

85

90

oss

[dB

]

75

80

Pat

hl

65

70

BS to MSR1 to MS

Fi 7 P th l l f t 4

0 0.2 0.4 0.6 0.8 160

Normalized snap shot

Figure 7. Path loss per cycle for route 4.

Preliminary Results – Route 4y

1

- Almost equal standard deviations for both cases.

0 7

0.8

0.9

Mean: -0.00 dBAbs

ciss

a

0.5

0.6

0.7Std: 2.78 dB

dow

fadi

ng <

A

0.3

0.4

Mean: 0.00 dBStd: 2.18 dBab

ility

of s

had

0.1

0.2

Pro

ba

BS to MSR1 to MS

-8 -6 -4 -2 0 2 4 6 80

Shadow fading [dB]

Figure 8. Cdfs of shadow fading for route 4.

Preliminary Results – Route 4y

In the relay MS case105

BS t MS - In the relay-MS case capacity drops when the MS moves in NLOS area. 95

100BS to MSR1 to MS

85

90

[bits

/s/H

z]

75

80

Cap

acity

[

65

70

0 0.2 0.4 0.6 0.8 160

Normalized snap shot

Figure 9. Capacity per cycle for route 4.

Preliminary Results – BS to Relayy y

0 9

1

Mean: 8.76 ns

R1 at 14 mR1 at 10 m

0.7

0.8

0.9Std: 2.36 ns

Abs

ciss

a

R1 at 10 mR1 at 6 mR4 at 14 m

0.5

0.6Mean: 8.96 nsStd: 0.03 ns

Mean: 94.32 nsStd: 1.68 nsM

S d

elay

< A

0.3

0.4

Mean: 8.50 nsStd: 0.16 ns

Std: 1.68 ns

obab

ility

of R

0

0.1

0.2Pro

Figure 14. Cdfs of RMS delay spread from BS to R1 at different heights and

0 20 40 60 80 1000

RMS delay [ns]

BS to R4 at the highest point.

Preliminary Results – BS to Relayy y

The highest R1 location103.5

- The highest R1 location is the best in terms of path loss. 102.5

103

R1 at 14 mR1 t 10 - Nevertheless, only 3.5

dB difference between the highest R1 and the

101.5

102

oss

[dB

]

R1 at 10 mR1 at 6 mR4 at 14 m

lowest R1.

100.5

101

Pat

hl

99.5

100

Fi 15 P th l l f BS t R1 t diff t h i ht

0 0.2 0.4 0.6 0.8 199

Normalized snap shot

Figure 15. Path loss per cycle from BS to R1 at different heights and BS to R4 at the highest point.

Preliminary Results - BS to Relayy y

- The lowest R1 location as1

R1 at 14 m The lowest R1 location as good as the R4.

- Approximately 6 bits/s/Hz diff b t th0 7

0.8

0.9Mean: 70.44 bits/s/HzStd: 0.28 bits/s/Hz

Mean: 67.23 bits/s/Hzscis

sa

R1 at 14 mR1 at 10 mR1 at 6 mR4 at 14 m

difference between the highest R1 and the R4.

0.5

0.6

0.7Std: 0.35 bits/s/Hz

apac

ity <

Abs

0.3

0.4

Mean: 72.56 bits/s/HzStd: 0.44 bits/s/Hz

Mean: 66.85 bits/s/HzStd: 0.17 bits/s/Hz

obab

ility

of c

a

0.1

0.2S d 0 b s/s/

Pro

66 67 68 69 70 71 72 73 740

Capacity [bits/s/Hz]

Figure 16. Cdfs of capacity from BS to R1 at different heights and BS to R4 at the highest point.

Preliminary Results – All Routes Combinedy

a) b)

Figure 17. Cdfs of RMS delay spread from BS to MS (a) and relay to MS (b) for all measured routes.

) )

y ( )

Preliminary Results – All Routes Combinedy

a) b)

Figure 18. Path loss curves from BS to MS (a) and relay to MS (b) for all measured routes

) )

MS (b) for all measured routes.

Preliminary Results – All Routes Combinedy

a) b)

Figure 20. Cdfs of capacity from BS to MS (a) and relay to MS (b) for all measured routes

) )

(b) for all measured routes.