Atec MG3670 User Manual
RADIO COMMUNICATIONS, EMI MEASURING TEST INSTRUMENTS
290 www.anritsu.com For product ordering information, see pages 4-7.
GPIB
For Measuring Signals of Digital Mobile Communication Systems in North America, Europe and Japan
The MG3670B/C, MG3671A/B and MG3672A are digital modulation
signal generators equipped with a high-performance quadrature
modulator. They output the signals needed to develop, test, and
evaluate digital mobile communications equipment and related devices with expansion units.
The MG3670B/C operates from 300 kHz to 2.25 MHz; the
MG3671A/B and MG3672A operate 300 to 2.75 MHz. Both provide
a stable and precise output as well as spectrum purity up to +13
dBm, even with modulation. In addition to testing receiver sensitivity
and excess input, they can be used for testing IF stage performance
and for evaluating device quality. A CMOS-level mode is provided for
I/Q signal input. The input frequency band covers the CDMA spread
spectrum band, expanding the range of applications.
The MG3670C/3671B/3672A can be expanded by rear panel extension connectors to use for auxiliary signal output functions special
to communication system. MG3670B/C, MG3671A/B and MG3672A
can be used in combination with up to eight modulation units and a
burst function unit simultaneously.
The MG0301C/0302A/0305A/0307A/0311A modulation units have
a continuous data generator capable of generating arbitrarily-programmable data signals and ITU-T specification PN9/15 stage
PRBS signals. They also have band-limiting filters and can output
I/Q baseband signals.
The MG0303A Burst Function Unit uses the frame and slot configuration stipulated by various communication systems and has a
modulation pattern generator function and a function for ramp control
of carrier burst signals. It can also handle data editing and scrambling.
The MG0310A Modulation Unit generates SS + QPSK/OQPSK
modulated (1.2288 Mcps) I/Q baseband signals, supporting the
CDMA system (TIA/EIA/IS-95) used in US Digital Cellular Systems
and the US Personal Communications Service (PCS).
Anritsu-developed DSP and ASIC technology is used in the
MG0310A to achieve superior waveform quality factor (ρ) and spurious emission characteristics. Channel multiplexed signals are supported for both forward and reverse links. With two MG0310A units
mounted in the MG3670C/3671B/3672A, all the test signals required
to conform to TIA/EIA/IS-95, -97, and -98 can be generated.
Simultaneous outputs from the rear extension connectors using long
and short codes, etc., support a wide range of applications including
RF related tests, IF stage performance tests, and device and module quality evaluation. (Option 25 is required to install the MG0310A
in the MG3670B/3671A. The auxiliary signal output function is not installed, so long/short codes cannot be output.)
The MG0312A QPSK Modulation Unit generates QPSK/OQPSK
modulated I/Q baseband signals at 8 high-speed bit rates between
500 kbps and 2.4576 Mbps. Built-in modulation data includes PN7/
PN9/PN15/PN23 pseudorandom patterns. Use over a wide range is
supported by multiple baseband filters and the Phase Encoding function, which allows modulation data to be voluntarily phase mapped
onto a constellation. At the 2.4576 Mbps rate, the evaluation of transmission section devices and modules can be performed such as RF
power amplifier for CDMA mobile stations.
The MG0314A Modulation Unit generates DS + QPSK modulated
(4.096/1.024 Mcps) I/Q baseband signals, supporting the W-CDMA
system specification. The various test signals required for W-CDMA
system experimentation can be generated by mounting the
MG0314A unit (it shares two slots) in the MG3672A.
DIGITAL MODULATION SIGNAL GENERATOR
MG3670B/C, MG3671A/B, MG3672A
300 kHz to 2.25/2.75 GHz
Communication systems
Units
PHS, PDC, PDC_H, MG0301C
NADC, TFTS π/4 DQPSK Modulation Unit
GSM, PCN (DCS1800),
MG0302A
CT2
GMSK Modulation Unit
DECT
MG0305A MG0303B
GFSK Modulation Unit Burst Function Unit
PACS, WCPE, PHS
MG0307A
π/4 DQPSK Modulation Unit
TETRA
MG0311A
π/4 DQPSK Modulation Unit
IS-95
MG0310A CDMA Modulation Unit
MG0312A QPSK Modulation Unit
W-CDMA
*
1
MG0314A W-CDMA Modulation Unit (only MG3672A)
*
1: Corresponds to the specification for W-CDMA system experimentation
Features
• Compatible with communication system measurement signals of
Japan, North America and Europe
• High modulation accuracy (≤1.8% rms vector error)
•
Outputs modulation signals suited to each communication system
•
Internal pattern generator with data-editing and scrambling functions
• Outputs IS-95 channel multiplex signal
• Outputs W-CDMA channel multiplexes signal (only for MG3672A)
• Wide range (30 MHz, 3 dB) I/Q Input (only for MG3672A)
For product ordering information, see pages 4-7. www.anritsu.com 291
RADIO COMMUNICATIONS, EMI MEASURING TEST INSTRUMENTS
6
Basic performance
• I/Q input supporting wide range of applications (only for
MG3672A)
The MG3672A is equipped with wide-band I/Q input from DC to 30
MHz (3 dB) so that wide-band quadrature modulation can be performed. This ensures that the MG3672A will remain fully compatible
with communication systems for which band expansion is planned in
the future.
Output level frequency characteristics
(50 Ω/0.5 Vrms mode)
30 k 100 k 300 k 1 M 10 M3 M
0
–1
–2
–3
Level (dB)
I/Q signal input frequency (Hz)
Frequency response for I/Q external modulation (typical values)
• I/Q signal I/O over broad frequency range (only for MG3670B/C,
MG3671A/B)
A quadrature modulator is built in, and external I/Q signals can be input to enable use with a variety of digital modulation modes, including QPSK, 8PSK, and M16QAM. The modulation band for I/Q input
signals is broad, covering the CDMA spread spectrum bandwidth.
Further, by adding an expansion unit, I/Q signal output can be ob-
tained from the internal data generator. Either 50 Ω or CMOS-level
compatibility can be selected for I/Q signals. Functions for adjusting
the level balance, offset, and phase are also provided for greater utility in evaluating modulators/demodulators and other devices.
Frequency response for I/Q external modulation (typical values)
• Excellent spectral purity
The SSB phase noise characteristic is an excellent –120 dBc/Hz or
less (100 kHz offset). The adjacent channel power characteristic excels as the interference signal source during modulation.
Output level accuracy at 1.9 GHz
• High modulation accuracy
A vector error of less than 1.8%rms is assured for output levels up to
+5 dBm over the entire operating frequency range. This high modulation accuracy is also achieved when the expansion units are used.
Even when the MG0301C and MG0303B units are installed and π/4
DQPSK modulation burst signals are generated, the vector error is
less than 1.8%rms. The MG3670B/C, MG3671A/B and MG3672A
enable measurement and quality evaluation of receivers and other
devices with more than adequate precision.
SSB phase noise at 1.9 GHz
• Large output level
Through use of new AGC circuitry, the MG3670B/C, MG3671A/B,
and MG3672A produce a highly precise output at levels down to
–143 dBm with stable frequency characteristics, not only for output
of unmodulated signals but also with π/4 DQPSK modulation accompanied by amplitude fluctuations and when outputting burst signals.
The MG3670B/C, MG3671A/B and MG3672A can generate a high
output level of up to +13 dBm over a broad range of frequencies, so
amplifiers are not needed even when testing receivers for excess
input and in testing other devices.
RADIO COMMUNICATIONS, EMI MEASURING TEST INSTRUMENTS
292 www.anritsu.com For product ordering information, see pages 4-7.
Pattern edit display
CDMA
MG0310A has various TIA/EIA/IS-95 frame formats and encoder
functions built-in for each channel type. For example, frame format
of signalling, communication, and Multiplex Option 1 are provided to
support Rate Set 1 (1200 ... 9600 bps) and Rate Set 2 (1800 ...
14400 bps) for the Traffic Channel. In combination with the Burst
Randomizer function, this allows system support at all rates, even for
reverse links. For internal data you can select either a PN7, 9, or 15
pseudo-random pattern, or a user settable 16-bit data repeating pattern, all fully editable. Operation can be from internal RAM user-definable sequence data or from external serial data.
Pattern setting display
W-CDMA (only for MG3672A)
MG0314A conforms to physical channel frame formats such as
Perch 1, Perch 2, DTCH, and Control, all of which correspond to the
specifications for W-CDMA system experimentation. Perch 1 enables user setting of the pilot symbol for synchronization, level, and
short code for long code masked symbol. DTCH enables setting of
the TPC Symbol at an interval of 16 time slots for each channel,
demonstrating its ability to handle many different situations and permitting greater user selection. Moreover, since the unit incorporates
the coding function for the frame formats of BCCH, FACH-L, DTCH,
and ACCH logical channels, CRC, convolution, and interleave conforming to these channels, it can be used for decoding evaluation,
etc. Other functions include the pilot symbol edit function, as well as
DTCH and ACCH transmission-off function.
Slot rise time waveform
Functions and performances with expansion unit
• Frame structure and data
TDMA
The MG0303B incorporates TDMA frames for various kinds of communication systems, as well as modulation patterns for each time
slot. Modulation patterns for device evaluation and for up/down
communication channels are provided and are output at the timing
required by the system. Hence the MG3670B/C, MG3671A/B, and
MG3672A can generate the burst signals needed to measure various
digital communication systems.
Time slots specified for different communication systems can be
selected freely. There is considerable freedom in choosing the modulation pattern within slots; either a PN9 or PN15 TCH segment can
be chosen, and part of the data outside the TCH segment can be edited.
The pattern memory function can be used to store and recall patterns.
A data scrambling function is provided as standard, and any initial
code can be set permitting more sophisticated evaluations and diagnostics using the MG3670B/C, MG3671A/B and MG3672A as a supposed base station and mobile equipment.
The internal modulation pattern can also be driven by an external
clock, so margin tests can be conducted by varying the clock pulse.
Pattern setting display
• Excellent leakage power characteristics during carrier-off
The rising and falling edges of burst signals have a gentle waveform
with a duration equivalent to two symbols, and the leakage power
during carrier-off characteristics are excellent.
PHS
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RADIO COMMUNICATIONS, EMI MEASURING TEST INSTRUMENTS
6
Frequency range 300 kHz to 2250 MHz (MG3670B/C), 300 kHz to 2750 MHz (MG3671A/B and MG3672A)
Accuracy Depends on installed reference oscillator
*
1
Frequency: 10 MHz
Carrier Internal reference Start-up characteristics: ≤1 x 10–7/day (after 30 min. warm-up), ≤5 x 10–8/day (after 60 min. warm-up)
frequency oscillator Aging rate: ≤2 x 10
–8
/day (after 24 h warm-up)
Temperature characteristics: ≤±5 x 10
–8
(0˚ to 50˚C)
External reference
input
10 MHz or 13 MHz (±10 ppm), 2 to 5 Vp-p, BNC connector (rear panel)
Reference output 10 MHz, 2 to 5 Vp-p, BNC connector (rear panel)
Level range
*
2
–143 to +13 dBm (resolution: 0.1 dB)
Frequency response ≤±1 dB (at 0 dBm output)
Output level/frequency ≤1000 MHz >1000 MHz
Level accuracy
*
2
–33 to +13 dBm ±1 dB ±2 dB
–123 to –33.1 dBm ±1.5 dB ±2 dB
Output –136 to –123.1 dBm ±3 dB ±4 dB
Impedance 50 Ω, N-type connector
Continuously Continuously variable output over 20 dB range (+8 to –12 dB) in 0.1 dB steps within upper and lower limits of any
variable level
*
2
output level
Level unit dBm, dBµ, µV, mV, V (dBµ, µV, mV, V selected terminate/open voltage display)
Interference ≤1 µV *Measured 25 mm from cabinet (except rear panel) with two-turn 25 mm diameter loop antenna, terminated
radiation with 50 Ω load, ≤+5 dBm output, CW
Spurious ≤–65 dBc (≥100 kHz offset, ≤±100 MHz bandwidth), ≤–50 dBc (≥100 kHz offset, full band),
Signal purity
(at ≤+5 dBm output) ≤–40 dBc [≥2.65 GHz, spurious at 5.4–Fout (carrier frequency) GHz], ≤–30 dBc (harmonics)
SSB phase noise ≤–120 dBc/Hz (100 kHz offset, CW)
Specifications (refer to the MG3670B/C, MG3671A/B, and MG3672A data sheet for more details)
• MG3670B/C, MG3671A/B, and MG3672A Digital Modulation Signal Generator
Continued on next page
• Superior spurious emission characteristics
Spurious emissions are guaranteed to be lower than –60 dBc (±900
kHz detuning, 30 kHz bandwidth) and –70 dBc (±1.98 MHz detuning,
30 kHz bandwidth) with MG0310A installed in the MG3670C/3671B/
3672A mainframe (for output level: 0dBm, baseband filter: SPEC 2).
Using this baseband filter gives a waveform quality factor (ρ) of
0.999 or better. This filter conforms to IS-95, providing 3-step switching. Selecting the best step for each evaluation item gives even higher performance. This excellent basic performance in a standard digital modulation signal generator makes it the ideal choice for the development and manufacture of digital mobile wireless equipment and
related devices/modules.
Modulation spectrum
(with MG0310A installed in the MG3670C/3671B/3672A)
• Excellent adjacent channel power ratio characteristics (only
for MG3672A)
Mounting the MG0314A on the MG3672A and setting the filter mode
to ACP (Adjacent Channel Power) yields an adjacent channel power ratio of –63 dBc (specification value) and –65 dBc (typ.) (with 0
dBm output, 1 channel output, 18˚ to 30˚C, 1.8 to 2.2 GHz). Moreover,
setting the filter mode to EVM (Error Vector Magnitude) guarantees
a modulation accuracy not exceeding EVM 5.0% (rms). The three filters are provided, enabling selection of performance according to the
evaluation items.
The baseband filter can be set in 0.05 steps, (α = 0.2 to 0.5), for
RNYQ and NYQ, as well as to α = 0.22 for RNYQ for W-CDMA system experimentation. The superior basic performance of the standard digital modulation signal generator permits development and
manufacturing of digital mobile radio equipment and related devices
and modules.
Adjacent channel power ratio at 5 MHz
(Optimizing the distortion of MS2602A Spectrum
Analyzer with MG0314A mounted into MG3672A)
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