A.5.2 Testing environment conditions

37.5443GPPConformance testingRelease 16TSUniversal Terrestrial Radio Access (UTRA) and Evolved UTRA (E-UTRA)User Equipment (UE) Over The Air (OTA) performance

This annex lists the testing environment conditions for all DUT types relevant to testing of radiated performance of multiple-antenna receivers. The use cases (positioning) discussed here are applicable for all methodologies, however the orientation and rotations described may be applicable for some methodologies only, and not for some other methodologies.

Table A.5.2-1 below lists the testing environment conditions along with a diagram and applicable references. The reference coordinate system and orientation of devices in that coordinate system is shown in Figure A.5.2-1 below that includes the mechanical alignment of a phone. For tablets the home button, charging connector and similar components can be used to define top and bottom. For laptops the definitions specified in 3GPP TR 25.914 [3] (and repeated here in Table A.5.2-1) are used. In the case of methodologies utilizing a spatial channel model in Figure A.5.2-1, the X axis points towards the channel model reference. For example in the case of an anechoic chamber utilizing 2D antenna array in the azimuth plane (XY plane from Figure A.5.2-1) this is the direction of the first probe at 0 degrees.

Figure A.5.2-1: Reference coordinate system and reference device orientation

First the terminology used below is defined here. Where possible consistency with [3], [30], [31] and [32] is sought.

Use Case (Position): the use case (position) indicates how the DUT is related to its environment. This includes the following example use cases: free space, beside head, beside head and hand, hand only, etc. Note that formerly this has been referred to as position in [6] as well as in [32]. Since to date only isotropic metrics have been used (TRP/TRS) the definition of positioning the device for a certain use case has been equivalent to orienting it relative to the environment. With the introduction of spatial channel models, the positioning for a specific use case has to be separated from the actual orientation relative to the spatial incoming signals. For some methodologies not utilizing spatial channel models this distinction might not be necessary.

Orientation: The orientation of the device in three dimensional space is defined using the three Euler angles – Ψ-yaw; Θ-pitch; Φ-roll as defined in [30] and [31] and linked to the reference coordinate systems and reference orientation from Figure A.5.2-1. Note that for most use cases practical considerations of how to position the DUT together with the phantom may determine the DUT orientation.

Rotation: Once positioned for a specific use case and oriented within the reference coordinate system, the DUT and phantom are rotated within the test zone to measure the performance under various spatial channel illuminations. The rotation is defined with the same Euler angles but expressed as vectors of equal size. An example is given below:

EXAMPLE: Consider a DUT measured in an anechoic chamber [29].
To measure the free space use case in the YZ plane (see Table A.5.2-1) for example at every 30 degrees the rotation vectors would be as follows:

Ψ = [0 0 0 0 0 0 0 0 0 0 0 0] – a vector of 12 zeros indicating no rotation from the reference position for any phi value below

Θ = [-90 -90 -90 -90 -90 -90 -90 -90 -90 -90 -90 -90] – a vector of 12 values equal to -90 indicating a constant pitch of -90 degrees for all phi values below

Φ = [0 30 60 90 120 150 180 210 240 270 300 330] – a vector of 12 distinct rotations from the reference position representing a rotation along the azimuth plane with a step of 30 degrees.

These vectors unambiguously define that the DUT is to be oriented with the screen up and rotated in azimuth every 30 degrees. The principal antenna pattern cuts (XY plane, XZ plane, and YZ plane) are defined in [30]. The XY plane cut corresponds to the absolute throughput testing condition applied to the CTIA reference antennas for the inter-lab inter- technique activity. They XZ plane and YZ plane cuts are shown for completeness and are not required for the absolute data throughput framework. The YZ plane cut corresponds to a device positioned with its screen up in a USB/WLAN tethering scenario and may be a useful testing point for handset devices expected to achieve performance metrics under such usage conditions.

Table A.5.2-1: Summary of possible testing environment conditions for devices supporting DL MIMO data reception

DUT type and dimensions

Testing condition

DUT orientation angles

Diagram

Handset, tablet, CTIA reference antennas

XY plane or P0

Ψ=0;
Θ=0;
Φ=0

Handset, tablet, CTIA reference antennas

XZ plane or L0

Ψ=90;
Θ=0;
Φ=0

Handset, tablet, CTIA reference antennas

Free space data mode screen up (FS DMSU) or
YZ plane or Face Up

Ψ=0;
Θ=-90;
Φ=0

Handset, tablet

Face Down

Ψ=0;
Θ=-90;
Φ=0

Handset, tablet

Free space data mode portrait (FS DMP)

Ψ=0;
Θ=-45;
Φ=0

Handset, tablet

Free space portrait tilt down

Ψ=0;
Θ=45;
Φ=0

Handset, tablet

Free space data mode landscape (FS DML)

Ψ=90;
Θ=-45;
Φ=0 – left tilt

Handset, tablet

Free space landscape tilt down

Ψ=90;
Θ=45;
Φ=0 – left tilt

Handset, width < 56mm

Left/right hand narrow phantom data mode portrait (LH/RH DMP)

Ψ=0;
Θ=-45;
Φ=0

Handset, 56 mm < width < 72 mm

Left/right hand PDA phantom data mode portrait (LH/RH DMP)

Ψ=0;
Θ=-45;
Φ=0

Handset width < 56 mm

Beside head and hand right/left (BHHR/BHHL)

Ψ=60;
Θ=6;
Φ=-90 – right side9

Ψ=-60;
Θ=-6;
Φ=90 – left side

Handset 56 < width < 72 mm

Beside head and hand right/left (BHHR/BHHL)

Ψ=60;
Θ=6;
Φ=-90 – right side

Ψ=-60;
Θ=-6;
Φ=90 – left side

LME

Laptop ground plane phantom

Ψ=0;
Θ=0;
Φ=0

LEE

XY plane

Ψ=0;
Θ=0;
Φ=0

NOTE 1: The orientation angles given in the table define a set of use cases and orientations relative to the spatial channel model. The rotation angles to be used for measurements are FFS. Methodologies not utilizing spatial channel models might not need to define any rotations but are expected to measure for the given use cases.

NOTE 2: The CTIA reference antennas have been defined for inter-lab inter-technique testing for the purposes of comparing MIMO OTA methodologies.

NOTE 3: For DMP, other pitch positions can be considered FFS.

NOTE 4: The absolute throughput usage mode is defined only within the framework of the CTIA reference antennas and is used for comparison of results within/across MIMO OTA methodologies.

NOTE 5: Screen up flat positioning reference corresponds to a possible USB/WLAN tethering case, details of implementing this DUT orientation condition such as additional cabling, etc., are FFS.

NOTE 6: Left/right/both hand phantoms for the DML usage scenario are not currently defined in 3GPP; until these phantom designs become available, is possible to only define a DML usage scenario in free space.

NOTE 7: For a symmetric 2D coverage of testing points in azimuth, DML left and right tilts are expected to produce identical results in free space. Once phantom designs become available, we expect the interaction of the phantom with the antennas to be dependent on the tilt.

NOTE 8: The 110 degree angle of the notebook screen opening is a standard reference for all measurements of antennas embedded in notebooks; as a result, the LEE measurement in free space is the principal XY plane cut with respect to this reference.

NOTE 9: The orientation angles for the talk mode position are only approximate. The phone positioning is defined as in [3] and in [32] relative to the SAM phantom.

The Data Mode Portrait (DMP) conditions are defined in TR 25.914 [3], and are included in this table for completeness. The Data Mode Landscape (DML) testing conditions are not currently defined in any standard testing methodology but benefit from a thorough treatment in academic literature [31]. This testing condition considers free space for all handset sizes until a DML phantom design becomes available, at which time the testing condition will be revisited.

The Laptop Mounted Equipment (LME) and Laptop Embedded Equipment (LEE) testing conditions are well defined in TR 25.914 [3] and constitute an XY plane cut measurement, given the proper orientation of the lid of the laptop ground plane phantom (in the case of LME) or of the laptop itself (in the case of LEE).

Given a 2D ring of symmetrically distributed probes [29]:

– The XZ plane is similar to the DML mode except for the additional 45 degrees pitch in the DML

– For the phantom case the tilt of the DML case is very relevant since the interaction of the phantoms with the antennas will depend on it – see Figure A.5.2-2.

Figure A.5.2-2: Left and Right tilts for landscape mode with left hand phantom
shown to interact differently with the antennas depending on the tilt