advances in millimeter wave measurements
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Advances In Millimeter Wave Measurements. Banded Differential and Pulse Measurements. Enabling Hardware Configurations Measurement Capability and Features Example of Four Port Device Measurements Pulsed Millimeter Wave Measurements. Agenda. Enabling Hardware. Direct IF access - PowerPoint PPT PresentationTRANSCRIPT
Advances In Millimeter Wave Measurements
Banded Differential and Pulse Measurements
Agenda
• Enabling Hardware Configurations
• Measurement Capability and Features
• Example of Four Port Device Measurements
• Pulsed Millimeter Wave Measurements
Enabling Hardware
PNA-X (N5242A)
MM-Wave Controllers (N5261A / 2A)
OML MM-Wave Modules
• Direct IF access• Dual spectrally pure sources, low phase noise• Frequency offset measurements• Built-in mm-wave module configuration• Integrated pulse measurement • Differential measurement capability• Multiport calibration capability
• Integrated RF and LO distribution• High current DC power distribution• Accurate control of RF power to modules• Flexibility to attach 2 or 4 banded modules
• 50 GHz to 0.5 THz• Optimized for PNA / PNA-X• Provides T/R and or T only modules• Close proximity to on-wafer DUT
N5261A / 2A Block Diagram
• Rear panel jumper for direct connection of RF to test set
• DC power supply for up to 4 mm-wave modules up to 0.5 THz
• 5 channel IF multiplexing
• ALC enable/disable for RF to module
• LO distribution for up to 4 modules
• Easily re-configured for 2 port support
• Allows for the use of a single and dual Source PNA-X
Agenda• Enabling Hardware Configurations
• Measurement Capability and Features
• Example of Four Port Device Measurements
• Pulsed Millimeter Wave Measurements
Measurement Capabilities• Standard S-Parameter Measurements
– S11……S44• Mixed Mode Measurements
– Differential P1 and P3 – Sdd11, Sds21, Scs21,
• Full 2-Port pulse on Port 1 and 2 • Support up to 0.5 THz mm-wave modules (without external power Supplies)
Feature Set
• New millimeter module configuration interface, requires new firmware update.
• Test set ALC control On/Off• Front or rear panel interconnect of RF to the mm-wave
test set• Presetting system maintains all RF and test set ALC
settings by the user.• Uses the multiport calibration for 4-port.• When used on a 2-port PNA-X requires option 551
Millimeter Module Configuration
• Multiple configurations including a standard PNA configuration
• Selection of supported mm-wave test sets
• Front and rear panel RF configuration for PNA-X
• ALC enable/disable for power control to module and pulse measurements
• Frequency setting for mm-wave modules including multiplier and port frequency
• Selection of PNA-X or external RF and LO sources
Agenda• Enabling Hardware Configurations
• Measurement Capability and Features
• Example of Four Port Device Measurements
• Pulsed Millimeter Wave Measurements
Example of a Four Port Device
Port 3Port 4
Port 1
Port 2
Magic Tee
Magic Tee Characteristics• Sum and difference ports are isolated
• Signals from the difference port are 180º out of phase
• Signals from the sum port remain in phase
• Applications for power combiner and signal division
Single Ended Measurements of a Magic Tee• Magnitude of port 3 and 4 with respect to the difference of port 1 • Isolation between sum and difference ports
Magnitude of port 3 and 4 with respect to the Sum of Port 2
Single Ended Measurements of a Magic Tee• Phase measurement of S32 and S42• Both measurements are in phase with each other
Differential Phase Ports 3 & 4 with respect to port 1
Differential Measurements
Port 3 Port 4
Port 1
Port 2
Port 3 Port 4
Port 1
Port 2
Measurement One: Difference Port SE - BAL Measurement Two: Sum Port SE - BAL
Difference Port SE- Balanced
Port 2+ Port 2-
Port 1
Sum Port Terminated
Sum Port SE- Balanced
Port 2+ Port 2-
Difference Port Terminated
Port 1
Verification of Measurements• Comparison of Single Ended and
Differential measurements
44434333444334334131
44433433444334334131
1413141311
2
1
2
1
2
2
1
2
1
2
22
SSSSSSSSSS
SSSSSSSSSS
SSSSS
Smm
Port 3 Port 4
Port 1
222221
222221
121211
cccdcs
dcddds
scsdss
SSS
SSS
SSS
Single Ended versus Balanced measurement
21413
12
SSSsd
Common Mode
Differential
21413
12
SSSsc
Agenda• Enabling Hardware Configurations
• Measurement Capability and Features
• Example Four Port Device Measurements
• Pulsed Millimeter Wave Measurements
Pulsed Signal in Time and Frequency Domain
fc
Pulse repetition frequency(PRF = 1/PRI)
1/PW
Time domain
Pulse width (PW)
Pulse repetition period (PRP)Pulse repetition interval (PRI)
Carrier frequency (fc)
Measured S-parameters
Frequency domain
Duty cycle = on time/(on+off time)
= PW/PRI
)())()(()( 1 tshahtxtrecttyprf
pw
0 1/prf-1/prft
......*
n(t-n(1/prf))
0 1/prf 2/prf-1/prf-2/prf
......rectpw(t)
0 1/2pw-1/2pwt
x(t)
))(())()(()( sprfshahprfsXspwsincpwsY
))(())(()( sprfshahprfspwsincpwsY
)()()( sprfshahspwsincDutyCyclesY
Mathematical Representation of Pulsed Signal
Pulsed Frequency Domain Spectrum
This is the spectrum of a pulsed signal at a pulse repetition frequency of 1.69 kHz and a pulse width of 7 us.
Pulsed Spectrum
-60
-50
-40
-30
-20
-10
0-2
0000
00
-150
0000
-100
0000
-500
000 0
5000
00
1000
000
1500
000
2000
000
Frequency Offset (Hz)
Pu
lse
d R
ep
on
se
(d
B)
Nulls at 1/pw
Pulsed Frequency Domain Spectrum (Zoom)
This is the same pulsed spectrum zoomed in on the fundamental frequency that is pulsed (center). Notice that the spectrum has components that are n*prf away from the fundamental. In pulse narrowband detection mode, ideally we would want a rectangular filter to filter out everything but the fundamental pulsed frequency.
Pulsed Spectrum(zoomed)
-0.0025
-0.002
-0.0015
-0.001
-0.0005
0
-2000
-1500
-1000
-500 0
500
1000
1500
2000
Frequency Offset (Hz)
Pu
lse
d R
es
po
ns
e (
dB
) Wanted frequency component
First spectral tone at 1.69kHz=prf
Pulsed S-Parameter Measurement ModesWideband/synchronous acquisition
– Majority of pulse energy is contained within receiver bandwidth
– Incoming pulses and analyzer sampling are synchronous(requires a pulse trigger, either internal or external )
– Pulse is “on” for duration of data acquisition
– No loss in dynamic range for small duty cycles (long PRI's), but there is a lower limit to pulse width
Receiver BW
Pulse trigger
Time domain Frequency domain
Pulsed S-Parameter Measurement ModesNarrowband /Asynchronous Acquisition
– Extract central spectral component only; measurement appears CW
– Data acquisition is not synchronized with incoming pulses (pulse trigger not required)
– Sometimes called “high PRF” since normally, PRF >> IF bandwidth
– “Spectral nulling" technique achieves wider bandwidths and faster measurements
– No lower limit to pulse width, but dynamic range is function of duty cycle
IF filter
IF filter
Time domain
Frequency domainD/R degradation = 20*log[duty cycle]
Agilent PNA-X Pulse Enhancements• Key Pulse Features:
– Internal Pulse Generators (option 025)• Up to 4 independent output channels that can be configured to drive internal
components (modulators) or external components• 60 MHz clock frequency(16.7 ns resolution)
– Internal Pulse Modulators• Can option with either 1 (option 021) or 2 (option 022) modulators (One per
source)• PW < 100 ns (rise time < 5 ns)
– Time resolution on receiver is less than 100 ns (20 ns typical) in narrowband mode– Enhanced Narrowband Detection Technique
• Substantial increase in measurement sensitivity and speed over current narrowband technique based on new patented pulse receiver architecture and algorithms
– Wideband mode current detection BW is 600 kHz (work is being done to increase this detection BW)
– Improved UI
One Box Test Solution
New
New
New
New
PNA-X Pulse Hardware Enhancements• The New PNA-X can be configured in a number of different pulse configurations
(more option information can be found in the PNA-X configuration guide):– 2-Port, 1 Source, 1 Modulator
• Provides pulse stimulus in one direction only (option 021)• Can use internal (option 025) or external pulse generators
– 2 or 4-Port, 2 Source, 1 or 2 Modulators• Provides pulse stimulus in one (option 021) or two (option 021 and 022) directions• Can use internal (option 025) or external pulse generators
New PNA-X Pulse Detection Techniques• The New PNA-X has added significant enhancements in the narrowband
detection mode using the narrowband IF path:– Digital Filter Nulling (Patent Pending)
• The digital filter nulls can be placed precisely on the pulse spectral lines since their location is known when using the internal pulse generators.
– Crystal Filter (Invention Disclosed)• There is a narrowband crystal filter (BW = 30 kHz) in the narrowband
pulse IF path which is used to increase the narrowband pulse mode sensitivity.
– SW Gate (Patented)• When using HW IF gating and internal pulse generation, we know the on
and off times of the gate (signal) precisely. Since the off times of the gate contain undesirable noise and/or residual gate isolation, the algorithm can replace the off times with an ideal off state (i.e. zeros) thereby improving the receiver sensitivity.
Pulsed Millimeter Wave Measurements• Support’s NB and WB Pulse• Configure the mm-wave system for modules
connected• Turn off ALC in the test set• Then start either Narrow or WB Pulse application• Configure the Pulse RF and Gate settings
RF ALC
Control
PNA-X Pulse Application – Main FormThe current pulse application (option H08) has been modified to include the use of the internal pulse generators and pulse modulators.
PNA-X Pulse Application – Pulse Profile
New PNA-X solution is substantially faster due to:
- Virtually no communication overhead using internal pulse generators
- Increased measurement sensitivity allows use of wider IF BW’s
77 GHz CW Pulse Profile
Automotive Radar Application Measurements
38-76 GHz Multiplier MMIC
76 GHz GsAs PIN Multithrow Switch
MMIC
19 GHz AMP
19-38 GHz Multiplier
76 GHz Mixer
LPF
0.01 uF
19-19.25 GHz OSC
Rad
iated P
ow
er
External Bandpass Filter
Autonomous Cruise Control Transceiver Module
Pulsed Millimeter Wave System Measurements
• Complete S-Parameter Measurements of 76 GHz PIN Switch
• Isolation between TX and RX channels
Test Set Ordering Configuration • N5262A (4-Port Test Set)
– Option 501 - Set of 4 RF, LO, IF and DC cables* 1.2 meter– Option 502 - Set of 4 RF, LO, IF and DC cables 2 meter– Option 503 - Set of 4 RF, LO, IF and DC cables 3 meter– Option 504 - Set of 4 RF, LO, IF and DC cables** 5 meter– Option 102 - Test interconnect for 2-Port PNA-X– Option 104 - Test Interconnect for 4-Port PNA-X
*Default for RF, LO and DC cables ** Not recommended for use with 325 or 500 GHz Modules (Loss)
• N5261A (2-Port Test Set)– Comes with standard 48 inch RF, LO, IF and DC cables– Option 102 – Test interconnect for 2-Port PNA-X– Option 104 – Test Set interconnect for 4-Port PNA-X
Agenda• Enabling Hardware Configurations
• Measurement Capability and Features
• Example Four Port Device Measurements
• Pulsed Millimeter Wave Measurements