Mobile WiMAX STC/MIMO/SISO Configuration

The Signal Studio for Mobile WiMAX advanced carrier mode supports testing of the STC/MIMO features needed for Wave 2 of the WiMAX Forum’s Radio Conformance Test, including:

Space-Time Coding (STC): Transmit diversity is supported to provide spatial diversity and reduce fade margin
Spatial Multiplexing (SM, also known as MIMO): With spatial multiplexing, multiple streams are transmitted over multiple antennas. With 2x2 MIMO, SM increases the peak data rate two-fold by transmitting two data streams. Two data stream multiplexing method are addressed in 802.16e-2005: horizontal encoding and vertical encoding. Only vertical encoding is supported in the Signal Studio for Mobile WiMAX following WiMAX Forum Mobile System Profile Revision-1.4.0. In UL, when each user has only one transmit antenna, two users can transmit collaboratively in the same slot as if two streams are spatially multiplexed from two antennas of the same user. This is called UL collaborative SM.

STC/MIMO/SISO Parameters Setting for DL-PUSC

Supported STC/MIMO/SISO Mode for DL-PUSC		Parameter Settings
Supported STC/MIMO/SISO Mode for DL-PUSC		Number of BS Antennas	Number of MS Antennas	Function Selection (In System Configuration Wizard)	Instrument Setup	Channel State	STC Type	Waveform Output Mode
Simulate Transmitter Antenna Signals	STC (Matrix A) 2-antenna	2	-	Multiple Antennae	Two Instruments	Off	Matrix A	Downlink Only (TDD) or Downlink Only (FDD)
	MIMO (Matrix B) 2-antenna	2	2	Multiple Antennae	Two Instruments	Off	Matrix B	Downlink Only (TDD) or Downlink Only (FDD)
	SISO	1	1	Single Antenna	One Instruments	Off	None	Downlink Only (TDD) or Downlink Only (FDD)
Simulate Receiver Antenna Signals	STC (Matrix A), one-antenna	2	1	Single Antenna	One Instruments	On	Matrix A	Downlink Only (TDD) or Downlink Only (FDD)
	STC (Matrix A), 2-antenna	2	2	Multiple Antennae	Two Instruments	On	Matrix A	Downlink Only (TDD) or Downlink Only (FDD)
	MIMO (Matrix B), 2-antenna	2	2	Multiple Antennae	Two Instruments	On	Matrix B	Downlink Only (TDD) or Downlink Only (FDD)
	SISO	1	1	Single Antenna	One Instruments	On	None	Downlink Only (TDD) or Downlink Only (FDD)

Collaborative SM/SISO Parameters Setting for Uplink

Supported Collaborative SM/SISO Mode for Uplink		Parameter Settings
Supported Collaborative SM/SISO Mode for Uplink		MS Antenna Number	BS Antenna Number	Function Selection (In System Configuration Wizard)	Instrument Setup	Channel State	Collaborative Burst	Waveform Output Mode
Simulate Transmitter Antenna Signals	Collaborative SM 1x2 to simulate the antenna on one of the MS	1	2	Single Antenna	One Instruments	Off	Added in PUSC Zone	Uplink Only (TDD) or Uplink Only (FDD)
	Collaborative SM 1x2 to simulate both antennas of the two MS1	1	2	Multiple Antennae	Two Instruments	Off	Added in PUSC Zone	Uplink Only (TDD) or Uplink Only (FDD)
	SISO	1	1	Single Antenna	One Instruments	Off	None	Uplink Only (TDD) or Uplink Only (FDD)
Simulate Receiver Antenna Signals	UL Collaborative 1x2 SM²	1	2	Multiple Antennae	Two Instruments	On	Added in PUSC Zone	Uplink Only (TDD) or Uplink Only (FDD)
Simulate Receiver Antenna Signals	SISO	1	1	Single Antenna	One Instruments	On	None	Uplink Only (TDD) or Uplink Only (FDD)

1. When fading is not turned on, this software creates waveforms that correspond to the transmitted signals from the two subscriber stations. The master instrument will have the signal from the first subscriber with pilot pattern A, while the slave source will have the signal from the second subscriber with pilot pattern B. In this case, you can not combine regular data bursts with the collaborative SM burst, because those would be coming from other subscribers.

2. When fading is enabled, this software generates the waveforms that would be received by the two base station antennae. In this scenario, you can include both regular bursts and the collaborative bursts. Two sets of fading channel parameters can be specified, each representing the conditions between one of the subscriber stations and the two base station antenna in a 1x2 SM configuration. The first set of channel parameters are applied to any regular bursts.