Built-in Spectrogram and Topographic Display Modes
Gate Sweep Function
1Hz Resolution Marker Counter
AM/FM Demodulation Analysis
886MHz IF Output for User’s Extended Applications
Various Interface: USB Host/Device, RS-232, LXI, Micro SD, GPIB (Optional)
8.4" large TFT LCD display with SVGA resolution of 800 *600
DVI-I Output for External Digital Display
Built-in Preamplifier, 50dB Attenuator, and Sequence Function
Optional 6GHz Power Sensor, Tracking Generator, Battery Back
GSP-930 is a 3GHz Spectrum Analyzer designed upon a new generation platform. The high stability, large screen display, light weight and compact size of GSP-930 benchmark a new standard for 3GHz spectrum analyzer in the market. Its advanced features, Spectrogram and Topography, greatly expand the application range and elevate the importance of a spectrum analyzer in the role as the irreplaceable RF analysis instrument.
GSP-930 provides a high frequency-stability of 25ppb (0.025ppm) and a very low noise floor of -142dBm (Pre-amplifier on) as the high sensibility measurement base. The flexible selection among 58 RBW ranges along with Spectrogram and Topographic features enable GSP-930 to capture and display transient, drifting and hopping signals in detail. The mixture of frequency domain information and time domain information facilitates the tracing of RF signal variations over time. Other remarkable features like Spectrum Emission Mask (SEM), Power Measurements, AM/FM Analysis and TOI/CNR/CSO/CTB measurements, make GSP-930 a useful instrument right fit into a broad range of applications.
The user friendly design of GSP-930 helps reduce user’s stress and anxiety in using a high-tech instrument. To help user easily get access to the regulations and definitions of the measurement terms under current operation, the built-in On-Screen-Help provides definition descriptionon the screen to guide user through measurement processes without checking into documents. The widely used Icons on the display clearly indicate the current setting and operation status of the product, allowing user to handle the measurement scenario all at a glance. The wake-up clock automatically turns on the power of GSP-930 at user’s pre-set time, which can be used to warm up the instrument in advance before the measurements are made to ensure the accuracy of measurement results. The Pass/Fail Limit function allows user to perform repetitive go/no-go measurements by template inspection instead of time-consuming value reading. The Sequence function provides an easy programming feature for user to edit and run measurement routines on GSP-930 screen without the need of a PC.
GSP-930 is equipped with various interfaces, including LXI, USB, RS-232 and GPIB (optional). The IVI driver is available for the remote control software development by means of LabVIEW or LabWindows/CVI. A Micro SD slot and a USB Host interface enable the memory size expansion for mass data storage. An IF output (886MHz) is provided as the intermediate frequency signal of RF inputfor users to develop their own applications. Carrying abundant communication interfaces, user-friendly operation, large screen display, light weight, compact size, and battery power operation(1), GSP-930 is developed upon a high-tech platform to provide ultimate customer benefits.
Remark (1): Battery pack is optional.
High Stability for both Frequency and Amplitude Measurements
GSP-930 carries a very high frequency-stability of 25ppb over temperature variation, superior to the 1ppm frequency stability of most spectrum analyzers available in the market. The high efficiency heat dissipation design and the temperature-controlled ventilation fan maintain a stable-temperature environment for GSP-930 circuitry operation, which contributes to the high accuracy of amplitude measurements in all time and greatly shortens the warm-up period at power on. To best utilize the advantage of high frequency-stability, GSP-930 features a Marker Frequency Counter function, which enables the high accuracy frequency measurements up to 1Hz resolution.
Marker Frequency Counter
Wide Measurement Range with Built-in Pre-Amplifier
GSP-930 carries an extremely low noise floor of -142dBm when the built-in Pre-amp is on, and -122dBm when the Pre-amp is off (2). With -142dBm noise floor and maximum input power up to +30dBm, GSP-930 provides a very wide measurement range, which makes the measurement of very small signal possible.
Remark (2) : Under "Auto On" mode, the preamplifier will be turned on automatically when the reference level is set at lower than -30dBm. Under "Bypass" mode, the preamplifier will be off in all time.
Digital IF Design provides Wide RBW Selections with High Accuracy
Adopting an advanced digital filter design, GSP-930 is able to provide 58 resolution bandwidth (RBW) selections. The RBW is selectable in 1-3 step increase from 10Hz to 3kHz, and in 10% step increase from 10kHz to 1MHz. The wide selection of RBW is able to maintain a consistent measurement result of filter shape, and enable the best accommodation between RBW and sweep speed to gain ultimate measurement accuracy. GSP-930 also provides RBW selections of 200Hz, 9kHz and 120kHz for EMI standard compliance. A unique analog to digital conversion design is used to achieve high-resolution amplitude measurements within full dynamic range. With high-resolution A to D conversion, GSP-930 greatly reduces the uncertainty and increases the accuracy of small signal measurements.
The RBW Range in GSP-930
Advanced Display Modes Paraphrase the Signal into Different Views
The conventional Spectrum Analyzer is not able to effectively measure transient signals or hopping signals due to the continuous update of current spectrum display. GSP-930, carrying Topographic technology, displays signals in various colors depending on the occurrence counts of each individual signal. This allows user to clearly distinguish transient signal, drifting signal and hopping signal from the entire spectrum of consistent input signals. The Topographic mode is especially useful to detect the transient interference signal in the telecommunication system, or to clearly display the transient behaviors of various types of telecommunication modulations like FSK, CCK and OFDM.
Topographic (top) display distinguishes two signals overlapping on the same frequency spectrum.
GSP-930 provides a powerful Spectrogram feature to simultaneously acquire Frequency Domain information and Time Domain information with dual-window display. Under Spectrogram mode, the X axis shows a line of frequency spectrum with different colors to represent different power levels of various-frequency signals, and the Y axis shows the time progress with current spectrum to always appear on the top of the display and with previous spectrums to roll down toward the bottom. The simultaneous provision of frequency domain information and time domain information makes Spectrum Analyzer a powerful instrument in most of the RF signal analysis applications.
Spectrogram (top) display shows a FSK signal
In addition to Topographic and Spectrogram display modes, the split window feature can also perform dual frequency band measurements under Spectrum mode. With upper display window and lower display window to show separate measurement results under separate settings, GSP-930 is very useful for harmonic signals measurements or far-off frequency signals measurements.
Spilt Windows display. 10MHz signal (top) and its 4th harmonic (bottom)
Four Traces with Display-and-Detector-Independent Settings
GSP-930 is able to display four measurement traces under four measurement modes, including Normal Trace, Max Hold, Min Hold and View, at the same time. The four measurement traces can also accommodate measurement results under various detecting modes, including PK+, PK-, Normal, Sample and Average.
Four traces with different display types and separate detector modes
Spectrum Emission Mask for a Variety of Communication Standards
GSP-930 includes Spectrum Emission Mask (SEM) measurement as a standard feature for RF emission power measurements of telecommunication systems. SEM is used to regulate the maximum power emission of a system during signal transmission as to avoid cross-over interference imposed on other systems in the neighboring transmission channels. GSP-930 has a variety of built-in SEM masks to comply with telecom standards, including 3GPP, 802.11b, 802.11g, 802.11n and 802.16. User can also create his/her SEM according to own definition.
Spectrum Emission Mask
In some of telecom systems, like Rader system and TDMA system, the signal transmission is done through periodical power emission applying TD (Time Division) technology. As the periodical power emission doesn't occur synchronously with the sweep time of spectrum analyzer, the TD signal measurement becomes a challenging task to the users. GSP-930, carrying Gate Sweep function, is able to do gated measurement over a complete time slot of periodically emitted signal. With external trigger signal input, GSP-930 is able to perform TD signal measurements perfectly.
Gate Sweep Function Off
Gate Sweep Function On
GSP-930 provides various Power Analysis functions for telecom channel measurements, including ACPR, OCBW, Phase Jitter and N-dB. With the display of channel bands in various color codes, and the split windows to show spectrum trace and measurement results simultaneously, GSP-930 is a very useful and convenient instrument for power analysis of telecom systems. The measurement function of Third Order Inter-modulation (TOI), caused by the nonlinearity characteristic of device or system, is also included to measure the inter-modulation distortion of two-tone signal.
Phase Jitter Measurement
To check the performance of CATV systems, GSP-930 has built-in functions for CNR, CSO and CTB measurements. Carrier to Noise Ratio (CNR) is the indication figure of transmission quality. Composite Second Order (CSO) measurement calculates the power difference between video carrier and composite second order beat. Composite Triple Beat (CTB) measurement calculates the power difference between video carrier and composite triple beat.
GSP-930 has enhanced AM/FM functions to do various parameter measurements such as AM Modulation Depth, FM Modulation Deviation, Carrier Power, Carrier Frequency Offset and SINAD etc. GSP-930 also provides listening feature for AM/FM demodulation analysis, allowing user to tune into AM or FM broadcasting and listen to the demodulated base band signals using ear phone jack.
To compensate the frequency characteristics of test apparatus and increase measurement accuracy, GSP-930 provides a Correction Table for user to fill in correction factors, which correct the measurement results based on the frequency characteristics of the test fixtures.
The built-in On-Screen-Help provides definition descriptions of test terminologies on the GSP-930 screen to guide user through measurement processes without checking into documents. The test terminologies carrying On-Screen-Help include:
1. The parameters of SEM, ACPR, Channel Power, OCBW, Phase Jitter and N-dB 2. The definitions of criteria of Pass/Fail test 3. The tips of Sequence editing
On Screen-Help and the Example of Correction Table
Limit Lind and Pass/Fail Test
The Limit Line function of GSP-930 sets the upper limit or the lower limit for amplitude measurements, and provides user with a quick view of Go/NoGo inspection without the need to get trace readings. Three methods are available for Limit Line editing. The point-by-point data entry, the Trace Data to Limit Line Data conversion, which creates limit line by setting the offset values of existing trace pattern, and the Marker Data to Limit Line Data conversion, which uses markers to create limit line. An open-collector alarm output is available at the rear panel, which allows user to connect an external alarm for sound or other indications of Go/No-Go test result.
Trace Data to Limit Line & Marker Data to Limit Line
Icon Symbols for Status Indication
The widely use of Icon symbols on the GSP-930 display allows user to see setting status and measurement results at a glance. This provides user with an easy view to handle the test scenario of GSP-930 all the time.
Wake-up Clock for Power-on Time Setting
The built-in wake-up clock enables the time pre-setting of GSP-930 power-on. This allows the setting of a prior warm-up time of the product at user's convenience, and enables accurate measurements according to the working schedule without waiting.
The Sequence function provides an easy programming feature for user to edit and run measurement routines on the GSP-930 screen without the need of a PC. GSP-930 can accommodate 5 Sequences of test routines with each Sequence routine to include up to 20 test steps. The multiple Sequences can also be chained freely to form a flexible test program like ATE test software.
Sequence provides an easy programming feature
GSP-930 provides standard LXI interface for LAN applications. Besides LXI, GSP-930 is equipped with various interfaces, including USB, RS-232 and GPIB (optional). A Micro SD slot and a USB Host interface, supporting NTFS/VFAT/FAT32/FAT16 formats, enable the memory size expansion for mass data storage. An IF output (886MHz) is provided as the intermediate frequency or the base band of RF input signal for users to develop further applications. The DVI-I interface, compatible with VGA/HDMI interface communication, offers the benefit to transfer the GSP-930 screen image to the external display equipment for remote image applications.
The optional PWS-06 Power Sensor provides Average Power measurement function for RF signals. The Power Sensor carries the specifications of ±0.15dB accuracy, 1MHz to 6.2GHz frequency range and -32dBm to +20dBm power measurement range. PWS-06 is powered by the USB port on GSP-930, and displays measurement results on the GSP-930 screen under Power Meter mode.
The Tracking Generator is available as an option of GSP-930 to meet the requirements of frequency response measurements of RF components or modules. As a portable instrument, GSP-930 uses a Li-ion battery pack, which complies with UN38.3 standard, for battery power operation.
PWS-06 RF Power Sensor and Power Meter mode on GSP-930
Software and Driver Support
A PC software is available with GSP-930 to support PC communication tasks through USB, RS-232 or GPIB ports. The user can acquire trace data from GSP-930 or store its display image on the PC, as the most popular applications. The acquired trace data can be saved as a text file for further analysis. The remote control of the instrument and the LAN/LXI applications can be done through this PC software as well. Besides this PC software, an IVI Driver is supported with GSP-930 to enable LabVIEW and LabWindows/CVI programming.
The compact size, light weight (4kg) and battery power operation of GSP-930 make it an ideal instrument for outdoor applications. The 8.4" large TFT LCD display provides a SVGA resolution of 800 *600, allowing high precision measurements with 601 data points for each trace display.
8.4" SVGA TFT LCD
9kHz ~ 3GHz
±2ppm max. (per year)
Over Temperature Frequency Stability
±0.025 ppm (0 ~ 50 °C)
10Hz~10kHz in 1-3-10 sequence 10kHz~1MHz, increment in 10% steps 200Hz, 9kHz, 120kHz for EMI Filter
Accessories PWS-06, USB Power Sensor GSC-009, Soft Carrying Case GRA-415, Rack Adapter Panel
Free Download PC Software, Remote monitor software IVI Driver, supports LabVIEW and LabWindows/CVI programming
3GHz Spectrum Analyzer
The PC Software, SpectrumShop, of GSP-9300.
GSP-930 IVI Driver for LabVIEW/LabWindows use. (It needs downloaded from NI website)
Manuals & Guides
PC Software Guide
The SpectrumShot Software operation document.
Quick Start Guide
GSP-930 Quick Start Guide.
GSP-930 Programming Manual
GSP-930 User Manual
Brochure & Datasheet
The datasheet of GSP-930 (pdf)
Can this also be used as a network analyzer to measure component bandwidth and amplifier?
A network analyzer can help the complex, or the vector, S parameter measurements. As I mentioned previously, a spectrum analyzer can only do scalar measurement, and the scalar measurement is the total results of the incident and the reflected waves. But if your application is for testing bandwidth or gain of component at both ends matched, spectrum analyzer can be helpful as network analyzer.
How to determine wireless transfer of RF energy across two 125kHz antenna coils built on fabrics through a 3GHz Spectrum Analyzer ? How to configure the critical measurement of 125 kHz RFID tag ?
For picking low frequency signal, a loop antenna with longer length is necessary and two 4-meters coils are wound such that two ends of each wire are soldered to the internal and ground pins of a BNC individually. Secondly, two loop antennas are attached to the upper and bottom acrylic plate and connect to TG output and RF input of GSP-830 individually. Then the RFID tag can be placed inside of the plates while testing. Thirdly, for the spectrum analyzer side, a 10dB attenuator at tracking generator output is necessary to attain the impedance match. Next step is to set the center frequency at 125kHz, Span 200kHz, reference level -10dB, scale is set to 5dB/div and RBW manually set at 30k for easier observation. Turn on the tracking generator and acquire its level as 0dB. Finally we can test the DUT (Device Under Test) by placing the DUT with center alignment to the up and bottom loop antennas. We may acquire that the desired signal is under modulation.
What is EMI and why is it important in device management?
Electromagnetic interference (EMI) occurs when the electromagnetic field in the environment interact with an implantable cardiac device, transiently disrupting or altering the device’s normal function. EMI constitutes one of the major concerns for patients with implanted cardiac devices.
Do pacemakers and ICDs (Implantable cardioverter-defibrillators) respond differently to EMI?
The most common EMI-ICD interaction and concern is that the EMI noise will be interpreted as ventricular fibrillation and initiate a shock. The pacing therapy from an ICD responds to EMI like a stand-alone pacemaker, except noise reversion in an ICD does not result in asynchronous pacing.
How can EMI affect the lead-device interface ?
Sometimes EMI (such as energy from electrocautery, cardioversion, or defrillation) can be shunted down the lead, resulting in thermal damage to the lead-tissue interface. This may result in a temporary or permanent rise in the stimulation threshold that is potentially detrimental.
What are EMI concerns in the work environment?
Potential sources of EMI in the work encironment include industrial welding machines, arc and spot welding, degaussing coils, and internal combustion engines. Industrial welding equipment exceeding 500A causes concern with cardiac devices. Low-amperage equipment (range 100-150 A) for hobby arc or spot welding likely does not cause significant interface.
As a research purpose, can a 3GHz Spectrum Analyzer be adopted on a novel method of finding digital-to-analog converters (DACs) input sequences to produce high-fidelity output waveforms ?
Error produced by a nonlinear DAC is represented by its spectra components. Successive power spectrum measurements by a 3GHz Spectrum Analyzer can be used to solved for the unknown amplitude and phase of compensation signals applied to the DAC inputs.
An Overview of Spectrum Analyzer.
The spectrum analyzer is the most widely applied measuring equipment for wireless communication devices, components or systems. It measures and presents the frequency spectrum distribution of the RF signal. Both the frequency and amplitude information can be measured and read through a spectrum analyzer. Nowadays the digital communication technique dominates the wireless communication system, but measuring frequency through a spectrum analyzer is still considered as a significant methodology for RF testing in the industrial field. To satisfy various spectrum analyzing needs, GW Instek provides three models: 3GHz, 2.7GHz, and 1GHz. Equipped with exceptional high performance and affordable price, the products are designed for the applications of wireless product manufacturers, service, design, educational institutes, and so on.
What do ACPR, OCBW Stand for?
ACPR stands for Adjacent Channel Power Ratio and sometimes the ACLR as in Adjacent Channel Leakage Ratio. It's the measurement of adjacent channel power leakage related to main channel. Greater dB number means greater (better) rejection ratio between channels. The PU1, PU2, PL1 and PL2 are the power of upper and lower adjacent channels 1 and 2. Pch is the power of the main channel. OCBW OCBW stands for Occupied Bandwidth. It measures the bandwidth that takes the specified percentage in a channel. Figure 2 illustrates the example of a 99% OCBW. Smaller OCBW number at the specified % means more concentrated power distribution in the channel.
What Does an FM Signal Look Like on a Spectrum Analyzer?
FM signal has more complicated phenomenon than AM signal on the time domain which is presented in Figure1. The frequency is modulated to sweep with specified deviation, and it is very difficult to measure the deviation from the time domain. But on the frequency domain, the carrier frequency, modulating signal frequency, deviation and bandwidth can be figured out directly.
Why Do the Noise Floor and Phase Noise Change with Different RBW in Spectrum Analyzer?
A wider RBW filters in more noise compared to a narrow RBW, therefore the noise floor level is proportional to the RBW bandwidth as in the 10*log (RBW) rule. Refer to Figure 1 as an example, where the noise floor at 30k RBW is 10dB higher than 3k RBW. From the above rule, 10*log (30k/3k) = 10dB.
What is TG? How can an user properly operate it?
A TG (Tracking Generator) acts as a sweep generator and its frequency is synchronized to the spectrum analyzer. So it is very useful for frequency response measurement. Before it is performed, normalizing the test setup is required just like a network analyzer. Refer to the operation manual for the detailed procedure. Besides, when the spectrum analyzer is set in "ZERO SPAN" which measures only one frequency, the TG will also output a fixed frequency signal without frequency sweep. In this case, TG is working as a signal generator that offers the same frequency range as the spectrum analyzer.
What is the difference between Frequency Counter and Spectrum Analyzer?
A frequency counter measures signal frequency. Basically it is designed to measure fixed frequency. If a frequency modulated signal is under measurement, the frequency variation will result in unstable measurement. Besides, frequency counters tend to measure the fundamental frequency without harmonic information. Since spectrum analyzers present spectrum distribution using marker functions, spectrum analyzers can tell the frequency in any point of the displayed signal. Spectrum analyzers provide complete information that frequency counters cannot.
What is GKT-001 General Accessory Kit Set used for?
The Accessory kit set provides primary wires and terminals for RF signal measurement, particularly an attenuator against a longer RF signal. So that an instrument burns itself.
What is GKT-002 CATV Accessory Kit Set used for?
The Accessory kit set provides an operational accessory set for a 75 ohm system. The general RF system is categorized into a 50 ohm type. Once 75 ohm components are under test with a 50 ohm system, resistance incompatibility is possible and measurement error is there. For example, CATV/HDTV are both this type.
What is GKT-003 RLB Accessory Kit Set used for?
Besides RF cable and terminals for connection, a 50 ohm terminal is provided to enable a user to perform a TG Normalize job for its reference level accuracy, primarily with RLB-001, ReturnLoss Bridge connection kits.
When is the GKT-006A EMI Probe Accessory Kit Set available?
Since any standards and normalized tests are not followed by product research or calibration diagnosis tests, the interference source is only found to give a better understanding for its frequency and energy; a diagnosis measurement equipment usually comes with a spectrum analyzer, a probe and preamplifier (not necessary). The GKT-006A provides a probe set with more added convenience upon diagnosis measurement.
A Near Field Probe is used to find out the signal required for analysis on the circuit board before seeking a possible interference on the circuit board. So that a probe is used to detect whether the signal here on the circuit board or components is interference source or internal signal; notably, since a probe is connected thru a spectrum analyzer to components or circuit boards, before being connected, it shall be recommended to confirm whether the power under test is within the range on a spectrum analyzer, possibly the circuit test after powering on.
What is required for the ATA-002 antenna use?
The GSP and ATA-002 are connected with an optional terminal while the ATA-002 antenna is optional for gauge receiving. GW Instek currently provides ADP-001 (N-BNC) to connect with both of them. It is recommended to purchase altogether with antenna, so that an antenna is unable to connect with SA.
What does M/F for N(M)-BNC(F) on the catalog signify?
There are usually 2 expressions on various terminals: M/F or P/J. M signifies Male; F, Female; P, Plug; J, Jack. In Chinese, Female terminal and Male terminal are such, e.g., ADP-002 is SMA(J/F)-N(P/M), which means that SMA is female terminal, N, male terminal.
N, SMA, BNC terminal are available on your Catalog. What shall I do, if I would purchase, once I see F terminal, M terminal, etc., elsewhere?
Since the popular terminals are N, SMA and BNC in RF field, the above are the interfaces for which our company can provide. Users are specific groups (e.g., F terminal are usually for CATV, M terminal is applied in wireless radio or car antenna fields), F and M terminals are occasionally applicable though. GW Instek currently has no such equipment; please consult the sales or other channels for purchasing.
What is the ADP-101 used for?
The ADP-101 is a connector each for 75 and 50 ohm, available when a 75 ohm system accessory set is under test for the GSP, e.g., CATV signal intensity. If signal comes directly thru the GSP, there is measurement error given for test; if signal comes thru the ADP-101 and a 75 ohm system is configured in Amplitude option, there is more accurate measurement for data test.
How is the RLB-001 applicable in the GSP connection?
RLB-001 is a Return Loss Bridge, primarily for return loss test (the characteristic curve under test), Source / Coupler / Load on RLB 001 each are connected with Source: TG / Coupler: RF / Load: the terminal under test. The theory states that TG signal sends thru Load terminal then returns to Coupler with amounts, such a ration, a Return Loss data.
What is the ATA-001 specification?
The ATA-001 is a general purpose antenna with adjustable length. People use it in different applications with different length. It is hard to give specification for an adjustable length antenna. Actually the antenna suppliers neither offer the electrical specification because of the above reason. They only offer the dimension information.
What is VSWR?
VSWR (Voltage Standing Wave Radio) is used to measuring wireless signal for its effective transmission power passing thru power source, transmission line to load (e.g., thru power amplifier, transmission line to antenna finally).
An ideal system has 100% energy transmission, signal source impedance, transmission line, characteristic impedance of other connectors and load impedance are accurately compatible with one another. Since there is no interference for an ideal transmission process, Signal AC voltage remains the same on both terminals. Impedance has the least possibilities of 100% compatibilities. In terms of the actual system, the impedance is impossibly 100% compatible. In this way, the power reflects against the power source partially so that causes an interference, along the transmission line, then produces a voltage Peak and wave trough.
VSWR is applicable in measure voltage variations, the ration of the highest voltage against the lowest voltage in a transmission line. As voltage remains unchanged for an ideal system, the VSWR is 1:1. Once there’s a generated reflection, voltage remains changed, VSWR amplifies—e.g., 1.2:1 or 2:1.
VSWR signifies the voltage ration for a transmission line, VSWR = |V(max)|/|V(min)|
V(max) signifies the maximum signal voltage value for a transmission line, V(min), the minimum value.
The equation is represented in the way calculating an impedance VSWR = (1+Γ)/(1-Γ)
Γ is the voltage reflection coefficient near load ends, determined by load impedance (ZL) and source impedance.：
Γ = (ZL-Zo)/(ZL+Zo), if load is completely compatible with a transmission line, Γ = 0, VSWR = 1:1.
What does dB differs from dBm?
dB signifies power gain unit, a relative value. While calculating A power, whether it is larger than B or less than, followed by the equation 10 log(A/B)=10(logA-LogB). E.g., A power is 40dBm, B power, 43dBm. That is, A is 3dB larger than B.
dBm signifies an absolute power value unit, formula: 10log(power value/1mW). E.g., if the emission power is 1mW, in dBm the converted value is indicated in the way like: 10log(1mW/1mW)=0dBm; for 40W power, 10log(40W/1mW)=46dBm.
If I would like to measure unknown signals, how shall I measure?
If an end customer doesn’t know about signal frequency range yet the signal is sent stably (e.g., sent by SG signal):
In Full span open mode, spot the signal frequency using Peak search
Drag to the central display area using Peak to Center function
Set the Span and Reference Level to view the optimal frequency range
Spot the more adequate frequency point and signal intensity by pressing Peak Search once
If an end customer doesn’t know about a signal frequency range and the signal is instable hopping signal (e.g., the mobile signal is the hopping signal).
In Full span open mode, capture the frequency range using the PK Hold function of Trace
Drag the signal to the central display area until the waveform remains stable by using the Peak to center function of the Peak Search
Set the Span scope and Reference Level to view the optimal frequency range
Press Peak Search to acquire the optimal frequency point and signal intensity, while PK Hold enables a stable waveform.
How does a spectrum analyzer differ from an oscilloscope?
The analyzed signal by a spectrum analyzer is the signal field; power signifies the LCD vertical axis, in dBm; frequency signifies a horizontal axis, in Hz.
An oscilloscope analyzes the signal for its time zone, the LCD vertical axis signifies Voltage, in V; the horizontal axis signifies Time, in S (second).
What is TG, what’s it used for, how to use it?
TG(Tracking Generator) relatively equals a sweep signal generator, its frequency syncs with a spectrum analyzer. Therefore TG is often applicable in Frequency Response measurement. For normal operation, standardization follows measurement, eliminates noises (e.g., Cable/Adapter), then spot the frequency range by way of relative measurement. In the other hand, If the spectrum analyzer is set for Zero Span, SA only carries out with a single frequency measurement. TG outputs a fixed frequency rather than a sweep. In the mean time, TG equals a signal generator. The frequency is consistent with the central frequency on a spectrum analyzer.
How is the mathematical relation between dBuV and dBm?
The dBuV definition is such：Voltage value against 1uV, the X value，the formula：20logX=A(dBuV) (1) A signifies the power value in dBuV.
The dBm definition is such: Voltage value against 1mW, the X value, the formula：10logX=B(dBm) (2)B signifies the power value in dBm, called Decibel Milliwatt.
The both relation is indicated：dBm+107=dBuV，please seek data relevant to an actual deduction process.
What does the spectrum analyzer Dynamic Range mean?
The Dynamic Range is where a spectrum analyzer has the capabilities to handle various signals simultaneously. The maximum Dynamic Range hold value is dependant upon the measurement being actually carried out with. The lower Dynamic Range hold limit is determined by natural noise or phase noise. The upper Dynamic Range hold limit is determined by 1dB compression point or distortion caused by a spectrum analyzer overload.
What is Third Inter-Modulation?
While a system works already within a non linear field, there generates a harmonic. While two tone signals are input simultaneously, the third inter-modulation harmonic is notably noted. As 1dB signal increases on the fundamental frequency, there generates 3dB Third Inter-Modulation. Particularly the 2 frequency come close together, each 2f1-f2 and 2f2-f1 for the Third Inter-Modulation is relatively close to f1 and f2. Particularly while f1 and f2 come closer, the more difficult the Third Inter-Modulation is unable to be filtered out by a wave filter completely.