CDMA vs. GSM: What’s Right For You?

If you’re looking for a new phone or even a new wireless carrier you’ve probably seen a few new acronyms being thrown around. Two of the most commonly used being CDMA and GSM. But what do they mean, why are they important, and what impacts do they have on you?

CDMA and GSM are the two global standards for telecommunication. CDMA stands for Code Division Multiple Access and GSM stands for Global System for Mobile. Neither is inherently better than the other but each has its own sets of strengths and weaknesses along with differences in technology that makes each unique.

In America, both technologies are used. If you have AT&T or T-Mobile as a carrier you are using a GSM network, if you are using Sprint, Verizon or US Cellular you are operating on a CDMA network.



Global System for Mobile is the most widely used mobile system. In fact, every country except the United States and Russia uses it exclusively. This is mostly because GSM was created and implemented first rather than any kind of technological superiority.

GSM networks rely on a TDMA, Time Division Multiple Access, to relay calls or other data over the network. This works by assigning time slots to each user and alternates between each interval while the devices are being used. This allows multiple devices to use the same frequency without interfering with each other. These intervals are also so small and they change so fast that we perceive them as a continuous stream of communication instead of hundreds and thousands of snippets.

Another important feature of GSM networks is the SIM cards that are in the back of phones. These store not only personal information such as contact information but also things such as your network identification and service subscription information. The pairing of these SIM cards with TDMA is what allows carriers to identify your device and your unique interval to allow you to use the network. One big upside to using a GSM network is that these SIM cards make it much easier to switch phones as so much information is stored in them and they are often compatible with other devices.


Code Division Multiple Access was developed during World War II to protect radio waves from being jammed by Nazis. This is why this technology can only be found in the United States and Russia. The reason other Allied powers do not use this technology is that in 1987 members of the European Union decided to make GSM their standard.

CDMA operates radically differently from GSM. Whereas GSM uses TDMA to separate users frequencies CDMA allows users access to the entire spectrum of frequency bands. They can use the entire spectrum because each call’s data is given a unique key and the receiver is able to read the key and divide the signals back into their original calls. Hence the name Code Division. This allows for not only more users on the networks but also for a more efficient use which translates to increased utilization.

One important thing to note is that many CDMA phones now have SIM cards in them. This is because these CDMA networks are implementing 4G and looking towards 5G networks where SIM cards are necessary.

What It Means For You

Despite all the technical mumbo-jumbo there really are very few actual differences between GSM and CDMA.  Both can provide quality cell service to customers if the carrier has built a proper network. If you’re hung up on any worries over the quality of service it won’t be because of the type of network the carrier offers.

That being said there are advantages to say having a GSM network that offers SIM cards to backup information or make it easy to switch and upgrade phones. Otherwise, it would probably be best to just choose whichever carrier has the best coverage and call quality around you.

Radiant Barriers and Your Cell Phone Signal

Radiant barriers have become increasingly popular as homeowners everywhere try and cut down on high energy costs. But can they also act as a barrier to your cell phone signal? Well, the short answer is yes, but we’ll take a closer look to see if they actually are as big of an issue as some are making it out to be.

What Is A Radiant Barrier?

A radiant barrier is a form of thermal insulation that prevents heat from thermal radiation. Most commonly this is a thin sheet of aluminum or other reflective metal. It is installed either on top of your roof or under it inside the attic, either way is equally effective. This thin layer then reflects a majority, about 97%, of the radiant heat back out through the roof into the world again. This can be a substantial amount of heat reduction and is especially effective in humid climates where traditional insulation is less effective.


A diagram showing how radiant barriers reflect thermal radiation and reduce the amount of heat in a home.

Can A Radiant Barrier Hurt Cell Phone Reception?

Like we said above yes radiant barriers can technically hurt your reception. However, it’s important to take into account a few things. First, most contractors only install the barriers over about 30-35% of your roof. Meaning that there is still 65-70% of a roof and four walls that you can receive a signal through. Also while aluminum and other metals used for these radiant barriers do interfere with cell phone signal they are often so thin that they don’t cause an issue. Think about it this way, you drive around in your car on the phone all the time and it works well, except for the occasional hiccup. Your car is made up of a metal probably very similar to or is actually aluminum and that frame doesn’t cause interference, simply because the sheet metal is thin. Radiant barriers are much thinner than a car frame.

The bottom line is while a radiant barrier can hurt your reception they often don’t. It has been noted that at times they have caused problems, however, this is typically in cases where they were already receiving poor reception. If you are one of the few unfortunate cases that this has happened to signal boosters have been shown to alleviate the problems extremely effectively. Consider one to fix your new dead zone.

With the rollout of 5G nationwide, radiant barriers are a huge hindrance to the performance of the device/connection. Cell phone signal booster technology is advancing along with the 5G rollout so we highly recommend investing in a 5G booster.

If you’re looking to get a mobile phone signal booster installed and you have a radiant barrier, reach out to us. Fill out our contact form here. At Signal Booster Installers, we want to recommend the best booster for you home, office/business, and vehicle. Our recommendations are carrier agnostic.

Wi-Fi Calling, An Alternative To Poor Signal


The Wi-Fi signal over a hand held phone. The new symbol for Wi-Fi calling.

Wi-Fi calling is an innovation that allows for users to text or make phone calls using their Wi-Fi signal instead of their cell signal. If you have poor cell reception but strong Wi-Fi signal this is a possible solution for you.

Wi-Fi Calling, The Technological Breakthrough

Wi-Fi calling is not a new or novel idea, while the technology to use this on your phones has been around since the mid-2000 ‘s people using the Internet to make calls has existed for much longer. Many of us are aware of software such as Skype or Cisco and they have been allowing people to talk over the Internet for much longer using VoIP, Voice Over Internet Protocol. For quite some time Skype was the gold standard and allowed many people to connect with friends, families, and coworkers. However, VoIP really exploded after the Apple innovation of FaceTime. While Skype had been providing a similar service FaceTime provided much higher quality audio and video and revolutionized how people used VoIP.

Is Wi-Fi Calling A Good Alternative?

Now that Wi-Fi calling has become a mainstream form of communication we have seen the adoption of it almost everywhere. All major carriers now support it each to varying degrees and it has become a useful tool that most can use. Coupled with the abundance of public hotspots at coffee shops, malls, and other public locations this has allowed networks to become much more comprehensive.  However, there are some drawbacks to this technology. FaceTime requires both devices to be iPhones, making calls still comes out of your regular minute allowance, the quality of the calls decreases in heavy use scenarios such as public hotspots, and perhaps most importantly connecting to public Wi-Fi exposes you to potential privacy breaches.

Wi-Fi calling has made leaps and bounds in the recent years to become a technology that has made life easier for those that get poor cell reception. It still has some drawbacks though and is not always a reliable replacement for having a strong cell signal. We of course always recommend a signal booster or amplifier to make sure your phone works as intended.

The FM Radio Revival on Your Mobile Phone

Earlier this week Samsung announced that they will begin enabling the FM radio chips in their new phone models.They will be partnering with NextRadio to bring this to all users that also have the NextRadio app installed. NextRadio currently partners with other cell phone manufacturers such as HTC, Motorola, and LG and allows users to listen to local radio stations through the app.

NextRadio the FM radio app that allows users to tune into local radio stations to listen.

Radio Revisited

Despite the perception that radio is a dated technology that is quickly being replaced in a digital age, it is proving to be quite resilient to changes in society. Not only does radio still have a broad reach, it still reaches 54% of the US population daily, it has been adapted to better fit into our digital lifestyles. Now almost 64% of those radio users listen over the Internet. While radio is not still in it’s Golden Age this amount of reach still makes it the third most powerful medium to reach people in the United States. As it has been such a large part of the development of both our culture and technology it will most likely still be a long time until radio fully disappears.


A cartoonish looking radio dial. showing someone switching from AM to FM radio channels.


New Uses for Old Tricks

Samsung joins the list of other cell manufacturers that manufacture their products with already activated FM radio chips amid recent calls to use mobile phones as public safety concerns grow. After the devastating hurricane season of 2017, the FCC has called for all cell phone manufacturers to activate the chip. Before the storms, many cell networks bottlenecked because of the increased usage. This made it difficult for authorities to provide important safety information and also it became more difficult to communicate with family or loved ones. Then after the storms most cell signals were knocked out however radio signals were still able to be transmitted. These chips can be used to save lives and shore up communication networks potentially saving lives.

Many phones already have an FM radio chip installed however not all of them have activated, if you are interested in this but don’t want to purchase a new phone do a quick Google search to see if your phone has a chip and how to activate it.

Of course one can always use a signal booster to attempt to stay connected to cellular networks but you have to remember that boosters only amplify existing signals, they don’t create signals of their own.

Is There an App for That?

If you go on any app store right now you can find hundreds of apps that promise to boost your signal. But if it’s as easy as that why isn’t everyone using them and more importantly why has no one told you about this magic app? Let me just tell you right now that this isn’t the post telling you that there is one.


Some of the top apps on the app store.


What’s Out There

There are plenty of “signal boosting” apps out there and many of them work to some degree, just not at boosting signal. Most of these apps would be much more honest if they would market themselves as performance enhancing apps because while they can improve performance they don’t improve signal strength. You can typically break these kinds of apps into two categories;

1. Speed-Up Apps – These apps speed your phone up by managing the processes running on your phone. This could mean that they are closing things in the background you are running or even stopping some background apps from starting up. This translates to efficiency with your phones RAM and processing power and could even extend your battery life.

2. Clean-Up Apps – These apps work by scanning through your files and caches and deleting old or junk files. You would be surprised how much a quick tune up like this can improve performance.


Know What You’re Putting on Your Device

While these apps can be useful don’t be tricked into thinking they’re improving your signal. The only way for your signal to improve is to increase the amount of signal received by your device. Either by increasing the output of your carriers tower or by increasing the gain to your device. While apps can’t affect that gain things such as antennas, repeaters, and amplifiers can have very large impacts. So at the end of the day if you truly need a boosted signal, sorry there’s not an app for that.

What Do Those Bars At The Top Of Your Phone Really Mean?

We’re all familiar with the bars at the top corner of our phones. They seemingly dictate if our phone’s are usable or if they’re just a paperweight for the time being. But what do those bars really tell you?

A set of bars like you would see at the top of your phone.

Scales, Relativity, and Bars

First it’s important to understand what the bars are trying to show you. Obviously they are trying to convey the strength of the signal, but you can’t see the “true” strength of the actual signal. You can tell that 5 bars is better than 4 and 4 is better than 3 and so on, but that isn’t very specific information. That’s because these bars are on an ordinal scale, or one that does not quantify its variables only orders them. Because of this limitation there is quite a bit of leeway as you could potentially have situations where while your phone displays 4 bars it is much closer to 3 than 5 and this is possibly affecting your ability to communicate. This can be useful for your carrier as it often allows them to round up, but it can be frustrating for consumers who don’t always get an accurate representation of their signal.


The Truth Behind the Bars

While the bars are indicative of signal strength they certainly are not always reliable for the average person to look at and understand off-hand. This is because there is no universal rule to how boosters need to be displayed. Each device manufacturer implements their own algorithm that determines how they display the number of bars. For example iPhones take into consideration signal-to-noise ratio whereas Androids do not. This leads to situations where iPhones can display a lower value than an Android even if both phones are on the same carrier, connected to the same tower, and right next to each other. The only true way to tell the strength of the signal is to change your display to read in decibels and not bars.


Accessing the Numbers

If you’re like me an prefer to get a real number than field test mode is just what you need. This is a special menu that shows you the numbers behind the bars and displays the value in decibels. It’s also important to know that the number it displays is going to be negative, and you’ll want it to be as close to 0 as possible. For example -60 is better than -90.  This is important because as the bars are on an ordinal scale you can’t get a true representation of how strong they are without this information as well. The ways to access this is different for every device but for example an iPhone user would go to their dialer and input *3001#12345#*.  For most Androids you can access Field Test Mode by going to “Settings” – “About Phone” – and either “Status” or “Network”. Some older phones require codes or alternate paths to access Field Test Mode, here is a guide that has many of them if you are having trouble finding yours.


The Bottom Line

If you still don’t really understand those little bars that’s alright. No one except the software engineers at Apple and Android truly do because the algorithms that determine them are kept secret. We can assure you though that except in rare circumstances more is better and you should always be looking to maximize them.

How To Fix Your Signal Now

If you need to fix your signal now and don’t have the time to wait around for your signal booster to ship and for you to install it here are five quick fixes to help.


Number One

Stop Moving – If you aren’t changing location your cellular device is able to work much more efficiently. It is using less of its resources to adjust your location and the corresponding network.

Number Two

Try a Different Spot – If you aren’t getting good signal right now try moving to a different location. Maybe something nearby such as a building or some trees are blocking the signal. If you’re indoors try moving by a window, if you’re outdoors try moving to some higher ground away from potential obstructions.


Picture from the famous Verizon marketing campaign with the tagline "Can you hear me now?". One of the tips to help you fix your signal was to move around similar to him.

Number Three

Go Outside – Like we stated above obstructions can dampen and sometimes completely block out your cell phone signals. And as you might imagine there are more of those obstructions on the ground. So go to the roof of your office or the second story of your home.


A cell phone sitting on some grass outside. One of the tips to fix your signal was to go outside to avoid obstructions.


Number Four

Use a Mobile Service Map Tool – There are many tools available to help you find the nearest cell tower that is probably providing your signal. You can use a website like or an app from the app store. Now that you know where the towers are you can try to position yourself either closer to the tower or around obstructions to prevent loss of signal.

Number Five

Combine These Tips – All of these tips will only provide small boosts to your signal. So in order to maximize your results it would be best to use many of them in combination. Remember more is better.


Look For a Permanent Fix

Of course none of these are permanent solutions, and I know we’re a bit biased but the best solution really is to get a signal booster. It’s the one way you can be sure that you’ll get a reliable, permanent, and hopefully the most satisfactory result.