Two Radar Detectors in the Same Vehicle?
兩臺進口雷達探測電子狗可以同時用在一輛汽車上嗎？
編譯：現在不流行冷漠臉了
Many people familiar with radar detectors know that false alerts can sometimes be caused by other radar detectors operating nearby。 But just because two radar detectors do not cause alerts on each other mean that they are not interfering with each other。 Here are a few reasons why you shouldn‘t run two radar detectors together in the same vehicle。
許多熟悉雷達探測電子狗的人都知道，有時在附近執行的其他雷達探測器電子狗也會造成誤報。即使兩個雷達探測器互不發出警報，也不意味著它們不相互干擾。這裡有幾個原因，你不應該執行兩個雷達電子狗一起在同一輛車上。兩個電子狗同時執行可能會導致誤報過濾功能的失效。
It can “Fool” the false alert filtering
Summary:
“Detector A” sees the police radar and also sees signals which leak from the other detector in the vehicle， “Detector B”。 Detector A thinks that the police radar is also leakage from Detector B， and tries to suppress the alert。 This results in diminished range or no alert at all from Detector A。
簡單總結一下：
電子狗A接收到雷達測速波的同時也收到了同車的另一臺電子發出出來的訊號波，電子狗A會認為來自測速雷達發射的波來自電子狗B，然後A電子狗就是啟用過濾功能而不發出報警， 這會導致檢測範圍減小或根本沒有警報。
The Details:
Radar detectors “sweep” the radar bands for police radar。 But what is not so obvious is that during their regular sweep， the detectors are also scanning for other non-police radar frequencies that， if detected， could block or prevent an alert。 This is due to filtering techniques which attempt to prevent Ka falsies from other detectors。 These techniques work wonders in normal situations。 But with another detector operating close by， range can be reduced or alerts can be completely blocked。
我詳細的說明一下：
電子狗工作的時候會掃描測速雷達的各個波段， 與此同時，在常規掃描過程中，電子狗也會掃描其他非測速雷達的頻率，如果偵測到的話，電子狗會阻止或阻止發出警報。 這是由於過濾功能，試圖阻止KA波段的誤報訊號來自其他探測器。 這些功能在正常情況下會工作正常。但是，另一個電子狗放在附近的時候，就很可能減少探測範圍或警報可以完全阻斷而不報，
Superhetrodyne radar detectors contain “Local Oscillators” （or LO for short）。 LOs create a radar signal that is utilized to “mix down” the incoming radar signal for detection。 Although the LO is generated inside the detector， in most cases the LO is “leaked” or “transmitted” from the radar detectors。 Many detectors on the road have a 1st LO that operates in the 11-12 GHz range。 The problem is， that these LOs also produce “harmonics” at multiples of the LO frequency。 So， in once classic example， an LO operating at 11。558 GHz would produce a harmonic at 34。674 GHz， well within the valid bandpass for a Stalker Ka radar unit。
超外差雷達電子狗包含“內建振盪器（簡稱LO）， 內建振盪器利用混合接收到的雷達訊號波而產生一個探測訊號， 雖然LO是在電子狗內部產生的，但在大多數情況下，LO是從電子狗中“洩漏”或“發射”出來的。在道路上，很多電子狗發出第一個LO， 訊號頻率範圍在11-12 GHz， 問題在於這些LO 也產生倍數“諧波”的LO頻率。， 因此，在一個經典的例子中，LO工作在11。558千兆赫，將產生一個諧波在34。674 GHz，以及有效的波段內為一個潛行者ka雷達單元。
Of course， this poses a problem for detector manufacturers： they must filter the Ka false alerts caused by these other detectors on the road， while still providing superior protection against Ka radar。
當然，這給電子狗製造商帶來了一個問題：它們必須過濾掉其他探測器在路上引起的KA誤報，同時仍然對ka雷達提供了優越的保護
Luckily， they have a novel technique at their disposal。 In the example above， not only is there a Ka signal produced at 34。674 GHz， but because the Ka signal is being produced by oscillator harmonics， there will also be signals present at the oscillator’s fundamental frequency of 11。558 GHz and the second harmonic at 23。116 GHz。 These signals would not be present with real Ka police radar since it transmits Ka directly。 So if the detector sees a signal around 34。674 GHz， the detector might also look for signals around 11。558 GHz， or the second harmonic at 23。116 Ghz。 If one or both of these were present， the detector would know that the Ka radar was a false harmonic from another detector and not police radar， and can suppress the alert as a false。
幸運的是，他們掌握了一種新技術來解決這個問題。 在上面的例子中，不僅有一個ka訊號產生於34。674千兆赫，但因為ka訊號是由振盪器諧波產生的，在振盪器的出現基波頻率為11。558 GHz和二次諧波23。116 GHz。這些訊號不會出現在真正的ka警用雷達中，因為它直接傳輸ka， 因此，如果檢測器看到大約34。674千兆赫的訊號，探測器也可以尋找大約11。558千兆赫的訊號，或者在23。116千兆赫的二次諧波。如果其中一個或兩個都存在，探測器就會知道ka雷達是來自另一個探測器的假諧波而不是警察雷達，並且可以將警報作為假警報加以抑制。
For example， if there is any interference seen in the 11 GHz and/or 22 GHz range， some detectors might “lock out” Ka band or a section of Ka band for a certain duration in order to prevent a false alert from another detector in the area。
例如，如果在11 GHz和/或22 GHz範圍內出現任何干擾，一些探測器可能在一定時間內“鎖定”ka頻帶或ka頻帶，以防止該區域中另一檢測器的假警報。
The whole technique gets pretty complex：
整個技術還是相當複雜的。
-the 11。558 GHz scenario mentioned above is only one example。 There are several frequency schemes used by different detectors， that detector manufacturers must account for in order to prevent K/Ka false alerts from other detectors。
-the oscillators in the detectors are sweeping
-the oscillators in some detectors will “park” at different points throughout their sweep
-上面提到的11。558千兆赫場景只是一個例子。有幾種頻率方案使用不同的探測器，檢測器製造商必須解釋，以防止K / ka假警報從其他探測器。
-探測器中的振盪器正在掃描
-某些探測器中的振盪器將在掃描時的不同點上“停車”。
One other technique that is sometimes used， is the detector will look for brief recurring “blips” of radar at certain frequencies which are indicative of the sweeping oscillator of another detector。 When the detector sees these blips， it might “lock out” or raise the threshold for a section of K or Ka band for a certain duration in order to prevent false alerts from the nearby detector。 Of course， if this other detector is in the same vehicle， then these blips never go away， and sensitivity is never restored as long as the interfering signal is present。
還有另外一種技術有時會被用到， 電子狗找短暫重複的來自另一個電子狗在一定的頻率掃描振盪器訊號， 當電子狗發現到這些訊號，它可能“鎖定”或延長一定時間以防止虛假警報訊號從旁邊的電子狗的某段K和Ka波段進入， 當然，如果這個電子狗是在同一輛車，那麼這些問題永遠不會消失，只要干擾訊號的存在靈敏度就不會恢復。
A detailed description of the methods used to filter alerts from other detectors is beyond the scope of this article。 Hopefully the above examples are enough to illustrate how running two detectors in the same vehicle can be a problem in light of the techniques used。
用於過濾來自其他檢測器的警報的方法的詳細描述超出了本文的範圍。希望上面的例子足以說明讓你明白在同一輛車上執行兩個電子狗會遇到的技術問題。
It can cause a detector to “park” often during it‘s sweep or switch to a “slow scan”
同時用兩隻狗可以使電子狗在掃描過程中“停止”，或者切換到“慢速掃描狀態”從而影響靈敏度，不報或誤報。
Summary:
“Detector A” is kept busy analyzing and rejecting false alerts due to leakage from “Detector B”， instead of looking for police radar。 This results in diminished performance。
總結：
“電子狗探測器A”正忙著分析和拒絕由於“電子狗探測器B”洩露而產生的誤報，而不是尋找真正的測速雷達。這會導致效能下降。
The Details:
Some detectors operate by sweeping quickly until they see a radar signal， then they “park” their LO or switch to a “slow scan” to get a closer look at the signal， in an attempt to determine if it is really police radar。 With another detector operating in close proximity， it might see leaked oscillator interference from the other detector and “park” or “slow scan” in order to analyze them。 Even if the detector determines that it isn’t police radar and does not trigger an alert， this will still have the effect of unnecessarily slowing down the overall sweep， reducing effectiveness against real police radar。 This can be especially critical to performance against weak instant-on at a distance， or POP。
細節說明：
一些探測器透過快速掃描直到發現到一個雷達訊號，然後他們停止他們的LO或切換到“慢速掃描模式”，以便更仔細地判斷訊號，以確定它是否真的是警用測速雷達。當另一個電子狗探測器靠近的時候，它可能會接收到到洩漏振盪器干擾波從其他電子狗探測器然後“停止”或“慢掃描”，以分析他們。即使電子狗探測器最後分析後確定它不是警察測速雷達，便不會觸發警報，但這仍然會造成不必要的減慢整個掃描，從而降低對真正警察測速雷達的效能。這對在遠距離或瞬間的弱瞬間的表現尤為關鍵。
It could raise the “noise floor”
這將提高電子狗的噪音干擾等級。
With microwave oscillators operating in close proximity， it has the potential to raise the “noise floor” in the radar bands。 Modern DSP detectors use averaging of multiple sweep samples in order to reduce the noise floor for maximum sensitivity。 Raising the noise floor would have the effect of making it so that a stronger signal would be necessary for the detector to be able to pick out radar signals from the noise。
隨著微波振盪器在近距離工作，它有可能潛在的提高在雷達波段的“噪聲干擾水平”。現代DSP電子狗探測器使用多個掃描樣品的平均值，以減低噪聲干擾的最大靈敏度。 提高噪聲干擾水平的作用是使電子狗探測器能從噪聲干擾中提取出真正的雷達訊號。
But I‘ve ran two detectors together before and they seemed OK。 I didn’t notice any difference。
不過實際的情況是我以前也同時用過兩個電子狗探測器，看起來不錯。我沒有發現到任何問題。
Sometimes two detectors running in the same vehicle will operate quite normally and there is no problem at all， at least part of the time。 It might be OK on some bands or frequencies， but problematic on others。 It might work just fine， except for certain times when the sweeps of the two detectors coincide with each other in a certain way。 And， there‘s no way to test this， or to “try it out and see if they interfere” because you just don’t know what the detectors are doing internally。
有時在同一輛車中執行的兩個電子狗探測器會正常工作，至少一部分時間沒有問題。可能在某些波段或頻率上是可以的，但對其他波段則有問題。它可能工作得很好，除了某些時候，兩個電子狗探測器的掃描在某種程度上是一致的。而且，沒有辦法測試這個，或者“嘗試一下，看看它們是否干擾”，因為你只是不知道電子狗探測器在內部做什麼。
The bottom line： there‘s no way to be sure when they might be interfering or when they’re not。
最終的結果是：沒有辦法確定他們什麼時候會干擾，他們有沒有產生干擾，無從得知。
What about the BEL STi Driver？
那麼貝爾sti電子狗是什麼情況？
People frequently ask the question： since the BEL STi Driver does not “leak” then it shouldn‘t interfere with another detector， right？ Actually， the BEL STi does technically still “leak”。 However， the leakage is so low that there is no detection from today’s RDDs （Spectre）。
很多人會經常問到的問題：貝爾sti沒有洩漏出訊號波，那麼它不應該干擾另一個電子狗探測器，對嗎？事實上sfi也是會洩漏出雷達訊號的，只是水平很低，難以用現在的條件檢測。
Consider the following facts：
Compared with today‘s high-end radar detectors， Spectre isn’t all that sensitive： it uses the same receiver as cheap “Quintezz” radar detectors sold overseas。
The normal operating range for Spectre is well beyond the separation you would have when operating two detectors in the same vehicle。
考慮以下情況：
用當今高階的雷達探測器做比較，Spectre不是那麼敏感，它使用相同的接收機作為廉價的“Quintezz”雷達探測器銷往海外。
Spectre的正常工作範圍遠遠超出了在同一輛車上操作兩個探測器時的距離。
So， could there be a problem with operating a radar detector which is more sensitive than Spectre at a distance which is much closer to the STi than the normal operating range for Spectre？ We have posed this question to some of the brightest minds in the industry， but there‘s no clear-cut yes or no answer。 The STi still has the potential to interfere。
那麼，操作比Spectre更靈敏的電子狗雷達探測器，距離更接近STI比Spectre的正常工作範圍呢？我們向業界最聰明的人提出了這個問題，但沒有明確的答案。STI仍然有潛在的干擾 。
Can other detectors interfere with the STi？ Definitely。
其他電子狗探測器會干擾STI嗎？答案是肯定的。
Conclusion
My recommendation： don’t run two detectors in the same vehicle if you are depending on them for protection。 As for comparing performance between two detectors： any results are always going to be questionable if they are obtained when running two detectors together。 For unquestionable results， test each detector individually against the radar source。 After that， if you want to run both together for demo purposes， go for it。 If the results happen to be significantly different than when the detectors were run individually， you‘ll know why。
最後的結論：
我的建議：不要在同一輛車上執行兩個電子狗探測器，如果你希望得到它們的保護。至於比較兩個探測器之間的效能：如果兩個電子狗探測器同時執行時，任何結果都將是有疑問的。想要得到肯定的結果，請把每一個電子狗探測器分別單獨對對雷達源進行測試。之後，如果你想同時執行兩隻狗測試一下 ，那就去試試。如果結果與電子狗探測器單獨執行時顯著不同，你就會知道原因了。
