"This article is mainly explained in accordance with the test methods and indicators of the 3GPP 38.101 and 38.521 5G receiving part, and as much as possible in the form of graphic, before 5G reception indicators, you can first understand the meaning of the following radio frequency parameters, for subsequent Read the cleaning barrier:
Refsens: Reference Sensitivity, Reference Sensitivity;
F_dl_low: the lowest frequency of the downlink operation.
F_dl_high: The Highest Frequency of The DownLink Operating Band;
CW: Continuous Wave, continuous wave, generally refers to sine wave;
5G NR: 5G New Radio, 5G unique radio styled;
Receive sensitivity should be one of the most basic concepts in the radio field, and is the minimum signal intensity that the receiver can be identified without exceeding a certain bit of error. It is said that the bit error rate, like LTE is a definition of the Age of GSM and WCDMA CS (Circuit Switch, Circuit Domain). In most cases, BER (Bit Error Rate) or Per (Packet Error Rate, Merble Packet Rate) is used to investigate sensitivity. The 5G NR and LTE use THROUGHPUT to characterize the sensitivity, and the smallest signal of the throughput is not less than 95%. The sensitivity of 5G NR is characterized.
Be
Let's first look at the calculation formula for sensitivity:
SENSITIVITY = 10Log10 (KT0) + 10 Log10 (BW) + NF + CNRMIN
Where 10 log10 (kT0) is indicated by a bottom noise-174dBm at room temperature, in absolute zero-273 ° C, we think that electrons are not exercise, this time noise is -174dBm, at room temperature, there is activity, but bottom The noise increase is very limited, in order to calculate, the bottom noise at room temperature is also -174dBm.
BW: band width, bandwidth;
NF: Noise Figure, the system's noise factor, generally refers to the first low noise unisex;
CNRMIN: Minimum Carrier Noise Ratio ALLOWED, the system demodulation allows minimum carrier noise ratio;
Take 5G NR's 20MHz business as an example to explain the origin of 5g NR sensitivity.
Sensitivity (LTE) = 10Log10 (KT0) + 10 Log10 (BW) + NF + CNRMIN
= -174dBM + 10LOG10 (19.08 * 10 ^ 6) + 6dB + (- 1) DB
= -174dBM + 72.8 + 6dB + (- 1) DB
= -96.2dBM
BW = 20MHz business actual occupied bandwidth 19MHz
Nf = 6db (here the NF here is the insert loss before the first level LNA plus the noise coefficient NF of the LNA itself)
CNRMIN: -1DB
Be
Be
7.4 Maximum Input Level Maximum Input Level
Test method: Uplift power setting is the maximum power-4db, DFT-S-OFDM QPSK, RB settings see the table mentioned below (in document 38.521-1), downlink configured as CP-OFDM 64QAM and CP-OFDM 256QAM
Test the maximum input level of uplink configuration
The throughput THROUGHPUT is not less than 95% when entering the size of the interference signal in the following table.
7.5 Adjacent Channel Selectivity Conditioning
Adjacent channel selectivity (ACS) is a measure of a receiver's ability to receive an NR signal at its assigned channel frequency in the presence of an adjacent channel signal at a given frequency offset from the centre frequency of the assigned channel.ACS is the ratio of The Receive Filter Attenuation On The Assigned Channel Frequency To The Receive Filter Attenuation On The Adjacent Channel (s).
The neighboring channel selective test is to add an interference signal adjacent to the primary channel, whether the case where the primary channel sensitivity deteriorates can meet the requirements. The ACS indicator is the ability of the terminal to suppress adjacent channel interference signals, and the signal size of the same size in the primary channel and adjacent channel, which reflects the narrowband digital rectangular filter of the baseband portion of the system. Steep filtering capability.
Test Methods:
2700MHz frequency band
Case1: The level of the main receiving signal is set to RefSens + 14dB, interfering power size refSens + 32.5dB, interfering signal bandwidth 5MHz, the frequency of interference signal ± 52.5 MHz.
Be
Case2: The level of the main receiving signal is set to -43.5dBm, interfering power size -25dBm, interfering signal bandwidth 5MHz, the frequency of interference signal ± 52.5 MHz.
3300MHz frequency band
CASE1: The level of the main receiving signal is set to Refsens + 14dB, interfering power size refSens + 45.5dB, interfering signal bandwidth BW, frequency ± BW of interference signals.
Be
Case2: The level of the primary receiving signal is set to -56.5dBm, interfering power size -25dBm, interfering signal bandwidth BW, frequency of interference signals ± BW.
Be
Note that the above interference signals are 5G NR signals set by the main signal as SCS.
Indicator requirements:
Be
ACS indicators are similar to ACLR, and ACLR is developed according to the average throughput of the cell and 5% CDF user (cell edge user) does not exceed 5%. In the entire communication system, upstream ACLRUE is a determinant, and the ACSUE in the downlink is a decision factor, because the indicator of the base station is required to be strict than the terminal, and the base station is not so sensitive to the device size, cost, etc., so it is easy to do. a little better.
7.6 Blocking Characteristics Block Features
The blocking characteristic is a measure of the receiver's ability to receive a wanted signal at its assigned channel frequency in the presence of an unwanted interferer on frequencies other than those of the spurious response or the adjacent channels, without this unwanted input signal causing a degradation of The Performance of the Receiver Beyond A Specified Limit.The Blocking Performance Shall Apply At All Frequencies Except Those At Which A Spurious Response Occurs.
The blocking characteristic reflects the ability of the receiver to receive normal signals in addition to a stray response or a throw frequency interference signal
7.6.2 in-Band Blocking
Test method: downlink CP_OFDM QPSK 1/3 Coderate;
& lt; 2700MHz frequency band, BW bandwidth useful signal, power: refSesn + 16db
Case1: In the useful signal center frequency ± (BW / 2 + 7.5 MHz), the transmission power is -56dBm, the bandwidth 5MHz interference signal;
Case2: In the widestable signal center frequency ± (BW / 2 + 12.5MHz), the position of 15 MHz above the frequency band, the transmission power is -44dBm, the interference signal of the bandwidth 5MHz;
Be
Be
3300MHz frequency band, useful signal bandwidth BW, power: refSesn + 6dB
CASE1: In the useful signal center frequency ± (BW + 150 MHz), the transmission power is -56dBm, the interference signal of the bandwidth BW;
Case2: In the widestable signal center frequency ± (BW + 250 MHz), the position of the 3 * BW of the band is until the position of the band, the transmission power is -44dBm, the interference signal of the bandwidth BW;
Be
Be
7.6.3 Out-of-Band Blocking
In the RRC connection state, select a location in the frequency band, the instrument sets a smaller downlink power, and test the continuous wave (CW) interference signal of different positions in frequency step in the frequency step in MIN (BW / 2, 5MHz), controlling the power uplink power. "Maximum Power-4DB"
Downlink setting: CP-OFDM QPSK 1/3 Code Rate; Upstream Settings: DFT-S-OFDM QPSK
2700MHz frequency band, useful signal bandwidth BW, power size: refsens + 16db;
Interference Range1: Interference signal of the position of 15 to 60 MHz from the edge of the frequency section;
Interference Range2: Interfering signal of 60 to 85 MHz on the edge of the frequency band;
Interference RANGE3: 1 to 85 MHz of the lower edge of the frequency section transmits power -15 dBm interfering signal at position 85MHz ~ 12.75 GHz on the edge of the frequency section;
Note: The interference signal power of the upper edge 6 GHz above the frequency band is set to -20dBm.
Be
Be
3300MHz frequency band, useful signal bandwidth BW, power size: refSens + 9db;
Interference Range1: Interfering signal of 3 * bw ~ 60 MHz on the edge of the frequency band;
Interference Range2: Interfering signal of -30 dBm of the maxima (60, 3bw) ~ 200 MHz edge up and down.
Interference Range3: Interference Signal of Power -15dBm of the Power -15dBm of the Max (200, 3BW) outside the edge of the frequency band;
Note: The interference signal power of the upper edge 6 GHz above the frequency band is set to -20dBm.
Be
Be
7.6.4 Narrow Band Blocking Narrowband Blocking
In the RRC connection state, set the CW interference signal, the power-55dBm, and the frequency point position is on the upper and lower edge of the signal bandwidth.
Upstream: CP-OFDM QPSK 1/3 Code Rate, useful signal bandwidth 20MHz, power REFSENS + 16DB, CW interference signal power-55dBm, distance center position ± 10.2075MHz
Be
Narrow Band Blocking Settings Requirements
7.7 Spurious Response Spiries Response
Test Methods:
The RRC is connected, and the same configuration is similar to the OOB test, and the frequency position of -44dBm continuous wave CW interference signal is used to test the frequency position in the OOB test.
2700MHz frequency band, 100MHz useful signal, downlink power is set to REFSENS + 16DB, interfering CW size-44dBm;
3300MHz frequency band, 100MHz useful signal, downlink power is set to refSens + 9dB, interfering CW size-44dBm;
The symbol of the qualified or not, is the throughput Throughput is not less than 95%.
Due to excessive interference signals caused by intermodulation, clock, crystal and other frequency components, the terminal is allowed to meet the index requirements of OOB in some frequency positions, while satisfying relatively loose spurious response requirements, which is also a spurious response The location.
7.8 Intermodulation Characteristics Trapentry Features
Intermodulation response rejection is a measure of the capability of the receiver to receiver a wanted signal on its assigned channel frequency in the presence of two or more interfering signals which have a specific frequency relationship to the wanted signal
The Wide Band Intermodulation Requirement Is Defined Using A CW Carrier And Modurated NR Signal AS Intercess 1 and Intercess 2 Respectively.
Attachment response reflects the radio frequency receiver in continuous wave (CW) (CW) with a particular frequency relationship and the anti-interference ability of the modulated 5G NR signal interference.
Specific indicators and test requirements:
2700MHz frequency band, FR1 CP-OFDM QPSK 1/3 CODERATE,
- Useful signal: 100MHz bandwidth, power size: refSens + 16dB
- Interference signal 1: CW interference signal, power-46bm, relationship with the useful signal center frequency: ± (BW / 2 + 7.5MHz)
- Interference signal 2: 5MHz bandwidth NR signal, power-46dBm, relationship with useful signal center frequency points: ± (BW + 15MHz)
3300MHz frequency band, FR1 CP-OFDM QPSK 1/3 Coderate,
- Useful signal: 100MHz bandwidth, power size: refSens + 6dB
- Interference signal 1: CW interference signal, power-46bm, relationship with useful signal center frequency: ± 2BW
- Interference signal 2: 100MHz bandwidth NR signal, power-46dBm, relationship with useful signal center frequency points: ± 4BW
5G RF Test RX Receive Metrics
CW and NR signal interference interference main signals for specific frequency relationships
7.9 Spurious Emissions stray radiation
.............. ..
Spurious radiation is a noise generated by the receiver or amplified in the radiocope position. As can be seen from the definition, when testing the receiving stray radiation, the transmitting circuit of the terminal, the local vibration LO and the radio frequency power amplifier PA of the radio frequency emitter must be closed.
The following table is the frequency range, test bandwidth and indicator requirements for receiving stray radiation.
Be
Be
The above diagram describes the relationship of receiving response characteristics, as an example of less than 2700 MHz, the first 5MHz is an ACS area, the second 5MHz is in-band blocking case1, the third one is all until the outside, 15MHz is all IN -Band blocking case2. Outside the OUT OF Band Blocking area, where OOB's Range2 and Range3 are all Spurious Response area, the lower limit frequency is 1MHz, and the upper frequency is f_dl_high + 12750 MHz.
Summary: This article explains the provisions and test methods of 5G NR RF reception indicators and corresponding significance, and the requirements of all communication systems, mainly including receiving sensitivity, channel selectivity, interposed, with external blocking response, miscellaneous Disperse response, etc. The receiving sensitivity reflects the ability of the system's receiving band, and the blocking response class indicator reflects the ability of the system to address various interference. "
Our other product:
