EDGE (Digital Demod)
This selection sets the instrument to the (3p/8 D8PSK) "Enhanced Data for Global Evolution" digital demodulation format. Use the same process to demodulate EDGE Enhanced Data for Global Evolution: A technology that gives GSMA and TDMA similar capacity to handle services for the third generation of mobile telephony. EDGE was developed to enable the transmission of large amounts of data at a high speed, 384 kilobits per second. (It increases available time slots and data rates over existing wireless networks.) as other digital demodulation formats.
adds a new filter: . Also two new digital demod error data results were added to the symbol table: and .
Use the VSA's standard preset feature to automatically configure the measurement parameters: Select the .
When using , note the following:
- Set the points per symbol to 1 point/symbol
Because signals incorporate rotation and the EDGE filter introduces ISI Inter-Symbol Interference: An interference effect where energy from prior symbols in a bit stream is present in later symbols. ISI is normally caused by filtering of the data streams. (inter-symbol interference), symbol locations in the vector and constellation diagrams should appear random. However, at one (the value set by the EDGE standard setup) the VSA removes the effects of ISI so a clean vector diagram can be viewed. Above one , the VSA does not remove the effects of ISI.
- EDGE reference filter:
The filter is available as the reference filter and is used for demodulating EDGE PSK Phase Shift Keying: A broad classification of modulation techniques where the information to be transmitted is contained in the phase of the carrier wave. signals. One of two filters may be used depending on the selection of the measured filter.
- When the measurement filter is set to , and the reference filter is selected, the reference filter will be a linearized Gaussian filter as defined by ETSI European Telecommunications Standard Institute: The European standardization body for telecommunications. (European Telecommunications Standard Institute) GSM Global System for Mobile Communications: Originally developed as a pan-European standard for digital mobile telephony, GSM has become the world’s most widely used mobile system. It is used on the 900 MHz and 1800 MHz frequencies in Europe, Asia and Australia, and the 1900 MHz frequency in North America and Latin America. 05.04.
- When the measurement filter is and the reference filter is selected, the reference filter will be the GSM 05.04 filter described above convolved with the filter.
- EDGE measurement filter:
The filter is available as the measured filter and is used for demodulating EDGE PSK signals. This filter is a windowed, raised-cosine filter that has an approximate 180 kHz kiloHertz: A radio frequency measurement (one kilohertz = one thousand cycles per second)., 6 dB bandwidth, as defined by ETSI (European Telecommunications Standard Institute) GSM 05.05.
The BT (Bandwidth Time Product) of the filter is fixed. The value of BT does not affect this filter.
- Pk EVM and 95% EVM error data results
The demodulation format adds two new error data results to the symbol table: and . is the mean (average) of the peak EVMs - one per measurement (it is a mean of the peaks, not a peak of the peaks). is the error-vector-magnitude (EVM Error vector magnitude (EVM): A quality metric in digital communication systems. See the EVM metric in the Error Summary Table topic in each demodulator for more information on how EVM is calculated for that modulation format.) below which 95% of the individual symbol EVMs occur.
- Adaptive Equalization
The Equalization Filter is only available when the is set to .
The BT Bandwidth Time Product (Bandwidth Time Product) of the reference filter is fixed. The value of BT does not affect this filter.
Additional Details
To learn how the VSA demodulates EDGE signals, see Digital Demodulation.
See Also
