L band
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| ITU Radio Band Numbers |
| ITU Radio Band Symbols |
| NATO Radio bands |
| IEEE Radar bands |
Contents |
[edit] NATO L band
The NATO L band is defined as the frequency band between 40 and 60 GHz (5–7.5 mm).
[edit] IEEE L band
The IEEE L band (20-cm radar long-band) is a portion of the microwave band of the electromagnetic spectrum ranging roughly from 1 to 2 GHz. [1][2] It is used by some communications satellites, and for some terrestrial Eureka 147 digital audio broadcasting (DAB). The amateur radio service also has an allocation between 1240 and 1300 MHz. The L Band refers to the frequency range of 950 MHz to 1450 MHz. It is the result of the downconversion of the received downlink satellite signals (C or Ku) by the LNB (Low Noise Block converter).
[edit] Military use
In the United States and overseas territories, the L band is held by the military for telemetry, thereby forcing digital radio to in-band on-channel (IBOC) solutions. DAB is typically done in the 1452–1492-MHz range as in most of the world, but other countries also use VHF and UHF bands.
[edit] GNSS
The Global Positioning System carriers are in the L band, centered at 1176.45 MHz (L5), 1227.60 MHz (L2), 1381.05 MHz (L3), and 1575.42 MHz (L1) frequencies.
- The Galileo Navigation System uses the L-band similarly to GPS.
- The GLONASS System uses the L-band similarly to GPS.
[edit] Telecommunications use
GSM mobile phones operate at 800–900 and 1800–1900 MHz. Iridium (satellite) phones use frequencies between 1610 and 1625MHz to communicate with the satellites
[edit] Digital Audio Broadcasting (Earth Orbital)
WorldSpace satellite radio broadcasts in the 1467–1492 MHz L sub-band.
[edit] DAB L band usage
The following blocks are used for T-DAB (terrestrial) broadcasts:
| Block | Centre Frequency |
|---|---|
| LA | 1452.960 MHz |
| LB | 1454.672 MHz |
| LC | 1456.384 MHz |
| LD | 1458.096 MHz |
| LE | 1459.808 MHz |
| LF | 1461.520 MHz |
| LG | 1463.232 MHz |
| LH | 1464.944 MHz |
| LI | 1466.656 MHz |
| LJ | 1468.368 MHz |
| LK | 1470.080 MHz |
| LL | 1471.792 MHz |
| LM | 1473.504 MHz |
| LN | 1475.216 MHz |
| LO | 1476.928 MHz |
| LP | 1478.640 MHz |
The following blocks are used for S-DAB (satellite) broadcasts:
| Block | Centre Frequency |
|---|---|
| LQ | 1480.352 MHz |
| LR | 1482.064 MHz |
| LS | 1483.776 MHz |
| LT | 1485.488 MHz |
| LU | 1487.200 MHz |
| LV | 1488.912 MHz |
| LW | 1490.624 MHz |
Note: Canada uses slightly different central frequencies for L-band DAB while in many European countries DAB is limited part of Band III due to television and mobile two way radio using the rest.
[edit] Physics issues relating to band use
The band also contains the hyperfine transition of neutral hydrogen (the hydrogen line), which is of great astronomical interest as a means of imaging the normally invisible neutral atomic hydrogen in interstellar space. Consequently parts of the L-band are protected radio astronomy allocations world-wide.
[edit] Optical communications L band
L band is also used in optical communications to refer to the wavelength range 1570 nm to 1610 nm.
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