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A signal strength and readability report is a standardized format for reporting the strength of the radio signal and the readability (quality) of the radiotelephone (voice) or radiotelegraph (Morse code) signal transmitted by another station as received at the reporting station's location and by their radio station equipment. These report formats are usually designed for only one communications mode or the other, although a few are used for both telegraph and voice communications. All but one of these signal report formats involve the transmission of numbers.
History[edit]
As the earliest radio communication used Morse code, all radio signal reporting formats until about the 1920s were for radiotelegraph, and the early voice radio signal report formats were based on the telegraph report formats.[citation needed]
Timeline of signal report formats[edit]
- The first signal report format code may have been QJS.[citation needed]
- The U.S. Navy used R and K signals starting in 1929.[citation needed]
- The QSK code was one of the twelve Q Codes listed in the 1912 International Radiotelegraph Convention Regulations, but may have been in use earlier.[citation needed]
- The QSA code was included in the Madrid Convention (Appendix 10, General Regulations) sometime prior to 1936.[citation needed]
- The Amateur radio R-S-T system signal report format currently in use was first developed in 1934.[citation needed]
- As early as 1943, the U.S and UK military published the first guidance that included the modern 'Weak but readable', 'Strong but distorted', and 'Loud and clear' phrases.[citation needed]
- By 1951, the CCEB had published ACP 125(A) (a.k.a. SGM-1O82-51), which formalized the 1943 'Loud and clear' format.[citation needed]
Radiotelegraph report formats[edit]
Q-Code signal report formats[edit]
The QSA code and QRK code are interrelated and complementary signal reporting codes for use in wireless telegraphy (Morse code). They replaced the earlier QSJ code.
Transmit 5 5 2 0
The currently the QSA and QRK codes are officially defined in the ITU Radio Regulations 1990, Appendix 13: Miscellaneous Abbreviations and Signals to Be Used in Radiotelegraphy Communications Except in the Maritime Mobile Service. They are also described identically in ACP131(F),:[1]
Signal | Question | Answer, Advice, or Order |
---|---|---|
QSA | What is the strength of my signals (or those of..)? | The strength of your signals (or those of..) is.. |
QRK | What is the intelligibility of my signals (or those of..)? | The intelligibility of your signals (or those of..) is..
|
R-S-T system[edit]
Amateur radio users in the U.S. and Canada have used the R-S-T system since 1934. This system was developed by amateur radio operator Arthur W. Braaten, W2BSR.[2][3][4][5] It reports the readability on a scale of 1 to 5, the signal strength on a scale of 1 to 9, and the tone of the Morse code continuous wave signal on a scale of 1 to 9.[6][7] During amateur radio contests, where the rate of new contacts is paramount, contest participants often give a perfect signal report of 599 even when the signal is lower quality, because always providing the same signal format enables them to send Morse code with less thought and thus increased speed.[citation needed]
No. | Meaning | ||
---|---|---|---|
R | S | T | |
9 | Extremely strong signals | Perfect tone, no trace of ripple or modulation of any kind | |
8 | Strong signals | Near perfect tone, slight trace of modulation | |
7 | Moderately strong signals | Near pure tone, trace of ripple modulation | |
6 | Good signals | Filtered tone, definite trace of ripple modulation | |
5 | Perfectly readable | Fairly good signals | Filtered rectified a.c. but strongly ripple-modulated |
4 | Readable with practically no difficulty | Fair signals | Rough note, some trace of filtering |
3 | Readable with considerable difficulty | Weak signals | Rough a.c. tone, rectified but not filtered |
2 | Barely readable, occasional word distinguishable | Very weak signals | Very rough a.c., very harsh and broad |
1 | Unreadable | Faint—signals barely perceptible | Sixty cycle a.c or less, very rough and broad |
SINPO code[edit]
SINPO is an acronym for Signal, Interference, Noise, Propagation, and Overall, which was developed by the CCIR in 1951 (as C.C.I.R. Recommendation No. 251) for use in radiotelegraphy, and the standard is contained in Recommendation ITU-R Sm.1135, SINPO and SINPFEMO codes.[8] This format is most notably used by the BBC for receiving signal reports on postcards mailed from listeners, even though that same standard specifies that the SINPFEMO code should be used for radiotelephony transmissions. SINPO is the official radiotelegraph signal reporting codes for international civil aviation [9] and ITU-R.[10]
Rating scale | S | I | N | P | O |
---|---|---|---|---|---|
Degrading effect of | |||||
Signal strength | Interference (man-made) | Noise (natural) | Propagation disturbance | Overall rating | |
5 | Excellent | Nil | Nil | Nil | Excellent |
4 | Good | Slight | Slight | Slight | Good |
3 | Fair | Moderate | Moderate | Moderate | Fair |
2 | Poor | Severe | Severe | Severe | Poor |
1 | Barely audible | Extreme | Extreme | Extreme | Unusable |
Radiotelephony report formats[edit]
R-S-T system[edit]
Amateur radio operators use the R-S-T system to describe voice transmissions, dropping the last digit (Tone report) because there is no continuous wave tone to report on.
No. | Meaning | |
---|---|---|
R | S | |
9 | Extremely strong signals | |
8 | Strong signals | |
7 | Moderately strong signals | |
6 | Good signals | |
5 | Perfectly readable | Fairly good signals |
4 | Readable with practically no difficulty | Fair signals |
3 | Readable with considerable difficulty | Weak signals |
2 | Barely readable, occasional word distinguishable | Very weak signals |
1 | Unreadable | Faint—signals barely perceptible |
SINPEMFO code[edit]
An extension of SINPO code, for use in radiotelephony (voice over radio) communications, SINPFEMO is an acronym for Signal, Interference, Noise, Propagation, frequency of Fading, dEpth, Modulation, and Overall.
Rating scale | S | I | N | P | F | E | M | O |
---|---|---|---|---|---|---|---|---|
Degrading effect of | Frequency of fading | Modulation | ||||||
Signal strength | Interference (man-made) | Noise (natural) | Propagation disturbance | Quality | Depth | Overall rating | ||
5 | Excellent | Nil | Nil | Nil | Nil | Excellent | Maximum | Excellent |
4 | Good | Slight | Slight | Slight | Slow | Good | Good | Good |
3 | Fair | Moderate | Moderate | Moderate | Moderate | Fair | Fair | Fair |
2 | Poor | Severe | Severe | Severe | Fast | Poor | Poor or Nil | Poor |
1 | Barely audible | Extreme | Extreme | Extreme | Very fast | Very Poor | Continuously over-modulated | Unusable |
Plain-language radio checks[edit]
The move to plain-language radio communications means that number-based formats are now considered obsolete, and are replaced by plain language radio checks. These avoid the ambiguity of which number stands for which type of report and whether a 1 is considered good or bad. This format originated with the U.S. military in World War II, and is currently defined by ACP 125 (G).,[11] published by the Combined Communications Electronics Board.[citation needed]
The prowords listed below are for use when initiating and answering queries concerning signal strength and readability.[citation needed]
Proword | Meaning |
---|---|
RADIO CHECK | What is my signal strength and readability; how do you hear me? |
ROGER | I have received your last transmission satisfactorily. |
NOTHING HEARD | To be used when no reply is received from a called station. |
Proword | Meaning | Conjunction | Proword | Meaning |
---|---|---|---|---|
LOUD | Your signal is very strong. | AND or BUT, depending on which prowords are combined | CLEAR | The quality of your transmission is excellent. |
GOOD | Your signal strength is good. | READABLE | The quality of your transmission is satisfactory. | |
WEAK | Your signal strength is weak. | UNREADABLE | The quality of your transmission is so bad that I cannot read you. | |
VERY WEAK | Your signal strength is very weak. | DISTORTED | Having trouble reading you due to interference. | |
FADING | At times your signal strength fades to such an extent that continuous reception cannot be relied upon. | WITH INTERFERENCE | Having trouble reading you due to interference. | |
INTERMITTENT | Having trouble reading you because your signal is intermittent. |
Use in analog vs. digital radio transmission modes[edit]
In analog radio systems, as receiving stations move away from a radio transmitting site, the signal strength decreases gradually, causing the relative noise level to increase. The signal becomes increasingly difficult to understand until it can no longer be heard as anything other than static.[12]:38
These reporting systems are usable for, but perhaps not completely appropriate for, rating digital signal quality.[citation needed] This is because digital signals have fairly consistent quality as the receiver moves away from the transmitter until reaching a threshold distance. At this threshold point, sometimes called the 'digital cliff,'the signal quality takes a severe drop and is lost'.[12]:38 This difference in reception reduces attempts to ascertain subjective signal quality to simply asking, 'Can you hear me now?' or similar. The only possible response is 'yes'; otherwise, there is just dead air. This sudden signal drop was also one of the primary arguments of analog proponents against moving to digital systems. However, the 'five bars' displayed on many cell phones does directly correlate to the signal strength rating.[citation needed]
Slang report formats[edit]
A report format commonly referred to as five by five.[citation needed] The report format ostensibly consists of two digits, each ranging from 1 to 5, resulting in 25 possible combinations, with five by five being the best signal possible out of 25 combinations.[citation needed] As no reliable source has been found documenting this format, it may simply be Cold War-era slang, inappropriately mapping the radiotelegraph signal report numbers to radio-telephony signals.[citation needed]
Some radio users have inappropriately started using the Circuit Merit telephone line quality measurement.[citation needed] This format is unsuitable for radiotelegraph or radio-telephony use because it focuses on voice-to-noise ratios, for judging whether a particular telephone line is suitable for commercial (paying customer) use, and does not include separate reports for signal strength and voice quality.[citation needed]
See also[edit]
- Perceptual Evaluation of Speech Quality (PESQ)
- Perceptual Objective Listening Quality Analysis (POLQA)
References[edit]
- ^'ACP 131(F) - Communications Instructions Operating Signals, April 2009'(PDF). Archived from the original(PDF) on September 6, 2012.
- ^'The Radio Amateur's Handbook'(PDF). p. 363. Archived(PDF) from the original on 4 March 2016. Retrieved 4 July 2015.
- ^'The RST Standard of Reporting'. Archived from the original on 24 September 2015. Retrieved 4 July 2015.
- ^Andrea, Steve. 'Can You Read Me Now?'(PDF). ARRL. Archived(PDF) from the original on 15 March 2016. Retrieved 4 July 2015.
- ^Arthur M. Braaten, W2BSR. 'A New Standard System of Reporting Signals'(PDF). ARRL. p. 18. Archived(PDF) from the original on 5 July 2015. Retrieved 4 July 2015.
- ^'Quick Reference Operating Aids (The RST System)'. Archived from the original on 2018-04-16. Retrieved 2018-04-10.
- ^'Ham Radio 'RST' Signal Reporting System for CW/Phone Operation'. University of Buffalo. Archived from the original on 14 October 2017. Retrieved 24 September 2017.
- ^'ITU-R Sm.1135, SINPO and SINPFEMO codes'(PDF). Archived(PDF) from the original on 2016-03-04. Retrieved 2018-04-10.
- ^'Procedures for Air Navigation Services: ICAO Abbreviations and Codes'(PDF). Archived(PDF) from the original on 19 April 2017. Retrieved 27 April 2015.
- ^'ITU-R Sm.1135, SINPO and SINPFEMO codes'(PDF). Archived(PDF) from the original on 2016-03-04. Retrieved 2018-04-10.
- ^'ACP 125 (G): Communications Instructions: Radiotelephone Procedures'(PDF). 28 November 2016. Archived(PDF) from the original on 19 February 2018. Retrieved 10 April 2018.
- ^ abImel, Kathy J.; Hart, James W. (January 2003). 'Understanding Wireless Communications in Public Safety'(PDF). FCC.gov. The National Law Enforcement and Corrections Technology Center–Rocky Mountain. Archived(PDF) from the original on May 21, 2015. Retrieved September 19, 2015.
External links[edit]
- Ham Radio RST Signal Reporting System for CW Operation, by Charlie Bautsch, W5AM
Retrieved from 'https://en.wikipedia.org/w/index.php?title=Signal_strength_and_readability_report&oldid=955952881'
WiFi router features got you stumped? Here’s your go-to guide on what really matters
If you perform a rain dance every time your WiFi goes out, it might be time for a new router. But understanding whether your router is up to par, or knowing what to look for in a new purchase, is much easier said than done. In addition to the perplexing industry terms like 802.11ac, dual band, and Mbps, routers look more like alien spaceships than technology for the home — leading you to wonder if you really need six external antennas. (The short answer? Nope.)
So, what features actually matter when it comes to router performance? Here’s a breakdown of the main protocols, speeds, other specs, and what you need to know.
1) Antennas: One antenna, two antennas, three antennas, four
Why it matters: How many antennas does it take to get a good signal? Do you need antennas at all? Whether you can see them or not, all WiFi routers have a transmit and a receive antenna, which are used to communicate wirelessly with your devices — from your laptops and smartphones to your new smart thermometer.
Transmit 5 5 20
How to choose: Intuitively, it makes sense that more antennas on a router correlates with better signal directionality and optimum speeds. This is true, to an extent. Multiple antennas create several streams for sharing data over radio channels, which brings more bandwidth to your devices. However, additional external antennas aren’t necessarily important — the software that drives the antennas is what really matters. When purchasing a router, think less about the number of antennas and more about added functionality. Specs like MIMO and MU-MIMO increase a router’s capacity to transmit and receive data, which makes your network faster.
2) Frequency channels: Battle of the bands
Why it matters: Macbooster 4 0 0 – maintains and optimizes your system. Single, dual, and tri-band refers to the frequency channels of a router. Single band routers operate at a lower frequency — on the 2.4GHz band — which has fewer channels and is therefore more crowded. In fact, most household appliances — such as your microwave, cordless phone, bluetooth devices — also operate on this frequency. Dual band routers support both 2.4GHz and 5GHz frequencies. The 5GHz band is capable of transmitting more data at higher speeds, but has a hard time routing around walls and furniture and can’t travel as far. Tri-band routers support a third band on the 5GHz channel, 5.8GHz.
How to choose: Whether your internet activity is limited to checking a few emails and scrolling through Facebook or you’re one of the 75 million Netflix power-streamers, dual band is your best bet. By utilizing both the 2.4GHz and 5GHz channels, a dual band router provides better speed and coverage, which is what matters most for great WiFi everywhere in your home. While tri-band routers may seem tempting, due to the limitations of the 5GHz band, you’ll only see minimal improvement in device performance. As the technology continues to improve, this will change in the future.
3) Wireless standard: The ABCs of 802.11
Why it matters: Whether they’re called protocols, standards, or specs, the terms around wireless internet compatibility are probably the most confusing and unfamiliar variables on a router. There’s 802.11a, 802.11b, 802.11g, 802.11n, and 802.11ac — because we all love alpha numeric names, right? 802.11ac and 802.11n are the standards you’ll find on most current routers, and the “a,” “b,” and, “g” standards are older and considered out of date.
How to choose: While some households can operate successfully on 802.11n, most consumers should use the newest standard, 802.11ac. This standard is faster and transmits more data, since it utilizes both the 5GHz and 2.4GHz bands. The downside is you need to be close to your router to use both channels — otherwise the router automatically defaults back to using only the 2.4GHz band. To get WiFi in every room, not just next to your router, consider a home WiFi system, like eero. Instead of relying on one router, multiple 802.11ac access points throughout your home connect in a mesh network. This way you’re always close to one and have a strong, stable connection.
4) Speed: The tortoise, the hare, and Mbps
Why it matters: Routers have all sorts of speeds listed on their packaging — from 8Mbps (megabits per second) to 1900Mbps. In theory, the higher the number, the faster your internet speed — but don’t get too caught up here. When comparing routers, you’ll likely see labels touting AC1200, AC1750, AC 3200, and so on. The “AC” refers to the wireless standard, while the number refers to the speed. For example, a router with a maximum link rate of 450Mbps on the 2.4GHz band and 1,300Mbps on the 5GHz band is considered an AC1750 router. But no individual client device, like your Apple TV, uses all that bandwidth at the same time, and each device can only use one band or the other. Plus, for normal WiFi usage you only really need 50Mbps down consistently throughout your home.
How to choose: It’s important to note that the speeds advertised on most traditional router packaging are theoretical maximums. The actual speeds you’ll see in your home depend on a variety of factors: your ISP connection, your modem, the layout and construction of your home, and much more. To choose a speed, consider your internet activity: for the average internet user, AC1200 routers are usually sufficient.
5) Security: WEP, WPA, and WPA2, oh my!
Why it matters: Router security is king when it comes to keeping the information on your network safe. The key acronyms to know when buying a new router are WEP, WPA, and WPA2. All three are WiFi protected access protocols, which encrypt your network and require that outside devices — and hackers — have a “key” to gain access.
How to choose: WEP is considered outdated and a piece of cake for any basic computer hacker to crack. WPA is better and more secure than WEP, but most experts and service providers recommendWPA2 security. Luckily, most modern routers are equipped with this protocol, but double-check for this when making your decision. Bottom line: if it doesn’t have WPA2, don’t buy it!
Where does eero fall when it comes to these specs? We hold ourselves to the highest of standards (pun intended). Check out our Help Center to learn more about how eero blankets your home in fast, reliable WiFi.