地图要么存储在设备上，要么通过连接接收。 导航是根据这些地图的数据库计算的。 这些可能是具有相关成本的许可项目，但如果您使用 Google 地图等服务，他们拥有 NAVTEQ 和其他公司的许可。
There's 3 satellites at least that you must be able to receive from of the 24-32 out there, and they each broadcast a time from a synchronized atomic clock. The differences in those times that you receive at any one time tell you how long the broadcast took to reach you, and thus where you are in relation to the satellites. So, it sort of reads from something, but it doesn't connect to that thing. Note that this doesn't tell you your orientation, many GPSes fake that (and speed) by interpolating data points.
If you don't count the cost of the receiver, it's a free service. Apparently there's higher resolution services out there that are restricted to military use. Those are likely a fixed cost for a license to decrypt the signals along with a confidentiality agreement.
Now your device may support GPS tracking, in which case it might communicate, say via GPRS, to a database which will store the location the device has found itself to be at, so that multiple devices may be tracked. That would require some kind of connection.
Maps are either stored on the device or received over a connection. Navigation is computed based on those maps' databases. These likely are a licensed item with a cost associated, though if you use a service like Google Maps they have the license with NAVTEQ and others.
GPS, the Global Positioning System run by the United States Military, is free for civilian use, though the reality is that we're paying for it with tax dollars.
However, GPS on cell phones is a bit more murky. In general, it won't cost you anything to turn on the GPS in your cell phone, but when you get a location it usually involves the cell phone company in order to get it quickly with little signal, as well as get a location when the satellites aren't visible (since the gov't requires a fix even if the satellites aren't visible for emergency 911 purposes). It uses up some cellular bandwidth. This also means that for phones without a regular GPS receiver, you cannot use the GPS at all if you don't have cell phone service.
For this reason most cell phone companies have the GPS in the phone turned off except for emergency calls and for services they sell you (such as directions).
This particular kind of GPS is called assisted GPS (AGPS), and there are several levels of assistance used.
GPS
A normal GPS receiver listens to a particular frequency for radio signals. Satellites send time coded messages at this frequency. Each satellite has an atomic clock, and sends the current exact time as well.
The GPS receiver figures out which satellites it can hear, and then starts gathering those messages. The messages include time, current satellite positions, and a few other bits of information. The message stream is slow - this is to save power, and also because all the satellites transmit on the same frequency and they're easier to pick out if they go slow. Because of this, and the amount of information needed to operate well, it can take 30-60 seconds to get a location on a regular GPS.
When it knows the position and time code of at least 3 satellites, a GPS receiver can assume it's on the earth's surface and get a good reading. 4 satellites are needed if you aren't on the ground and you want altitude as well.
AGPS
As you saw above, it can take a long time to get a position fix with a normal GPS. There are ways to speed this up, but unless you're carrying an atomic clock with you all the time, or leave the GPS on all the time, then there's always going to be a delay of between 5-60 seconds before you get a location.
In order to save cost, most cell phones share the GPS receiver components with the cellular components, and you can't get a fix and talk at the same time. People don't like that (especially when there's an emergency) so the lowest form of GPS does the following:
Get some information from the cell phone company to feed to the GPS receiver - some of this is gross positioning information based on what cellular towers can 'hear' your phone, so by this time they already phone your location to within a city block or so.
Switch from cellular to GPS receiver for 0.1 second (or some small, practically unoticable period of time) and collect the raw GPS data (no processing on the phone).
Switch back to the phone mode, and send the raw data to the phone company
The phone company processes that data (acts as an offline GPS receiver) and send the location back to your phone.
This saves a lot of money on the phone design, but it has a heavy load on cellular bandwidth, and with a lot of requests coming it requires a lot of fast servers. Still, overall it can be cheaper and faster to implement. They are reluctant, however, to release GPS based features on these phones due to this load - so you won't see turn by turn navigation here.
More recent designs include a full GPS chip. They still get data from the phone company - such as current location based on tower positioning, and current satellite locations - this provides sub 1 second fix times. This information is only needed once, and the GPS can keep track of everything after that with very little power. If the cellular network is unavailable, then they can still get a fix after awhile. If the GPS satellites aren't visible to the receiver, then they can still get a rough fix from the cellular towers.
But to completely answer your question - it's as free as the phone company lets it be, and so far they do not charge for it at all. I doubt that's going to change in the future. In the higher end phones with a full GPS receiver you may even be able to load your own software and access it, such as with mologogo on a motorola iDen phone - the J2ME development kit is free, and the phone is only $40 (prepaid phone with $5 credit). Unlimited internet is about $10 a month, so for $40 to start and $10 a month you can get an internet tracking system. (Prices circa August 2008)
It's only going to get cheaper and more full featured from here on out...
Re: Google maps and such
Yes, Google maps and all other cell phone mapping systems require a data connection of some sort at varying times during usage. When you move far enough in one direction, for instance, it'll request new tiles from its server. Your average phone doesn't have enough storage to hold a map of the US, nor the processor power to render it nicely. iPhone would be able to if you wanted to use the storage space up with maps, but given that most iPhones have a full time unlimited data plan most users would rather use that space for other things.
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在 24-32 颗卫星中，您至少必须能够接收 3 颗卫星，它们每颗都广播来自同步原子钟的时间。 您在任何时间收到的时间差异可以告诉您广播到达您需要多长时间，从而知道您相对于卫星的位置。 所以，它有点从某些东西中读取，但它并不连接到那个东西。 请注意，这并不能告诉您您的方向，许多 GPS 通过插入数据点来伪造方向（和速度）。
如果不计算接收器的成本，这是一项免费服务。 显然，有更高分辨率的服务仅限于军事用途。 这些可能是解密信号的许可证以及保密协议的固定成本。
现在您的设备可能支持 GPS 跟踪，在这种情况下，它可能会通过 GPRS 等方式与数据库进行通信，该数据库将存储设备发现自己所在的位置，以便可以跟踪多个设备。 这需要某种连接。
地图要么存储在设备上，要么通过连接接收。 导航是根据这些地图的数据库计算的。 这些可能是具有相关成本的许可项目，但如果您使用 Google 地图等服务，他们拥有 NAVTEQ 和其他公司的许可。
There's 3 satellites at least that you must be able to receive from of the 24-32 out there, and they each broadcast a time from a synchronized atomic clock. The differences in those times that you receive at any one time tell you how long the broadcast took to reach you, and thus where you are in relation to the satellites. So, it sort of reads from something, but it doesn't connect to that thing. Note that this doesn't tell you your orientation, many GPSes fake that (and speed) by interpolating data points.
If you don't count the cost of the receiver, it's a free service. Apparently there's higher resolution services out there that are restricted to military use. Those are likely a fixed cost for a license to decrypt the signals along with a confidentiality agreement.
Now your device may support GPS tracking, in which case it might communicate, say via GPRS, to a database which will store the location the device has found itself to be at, so that multiple devices may be tracked. That would require some kind of connection.
Maps are either stored on the device or received over a connection. Navigation is computed based on those maps' databases. These likely are a licensed item with a cost associated, though if you use a service like Google Maps they have the license with NAVTEQ and others.
GPS，即美国军方运营的全球定位系统，免费供民用使用，但事实上我们是用纳税人的钱来支付它的。
然而，手机上的 GPS 有点模糊。 一般来说，打开手机中的 GPS 不会花费您任何费用，但是当您获取位置时，通常会涉及手机公司，以便在信号弱的情况下快速获取位置，以及在有信号时获取位置。卫星不可见（因为即使出于紧急 911 目的而看不到卫星，政府也不需要修复）。 它会占用一些蜂窝带宽。 这也意味着，对于没有常规 GPS 接收器的手机，如果您没有手机服务，则根本无法使用 GPS。
因此，大多数手机公司都会关闭手机中的 GPS，紧急呼叫和向您出售的服务（例如方向）除外。
这种特殊类型的 GPS 称为辅助 GPS (AGPS)，并且使用多个级别的辅助。
GPS
普通的 GPS 接收器监听特定频率的无线电信号。 卫星以此频率发送时间编码消息。 每颗卫星都有一个原子钟，并发送当前的准确时间。
GPS 接收器找出它可以听到哪些卫星，然后开始收集这些消息。 这些消息包括时间、当前卫星位置和一些其他信息。 消息流很慢——这是为了节省电力，而且因为所有卫星都以相同的频率传输，如果它们速度慢，就更容易被发现。 因此，以及良好运行所需的信息量很大，常规 GPS 可能需要 30-60 秒才能获取位置。
当 GPS 接收器知道至少 3 颗卫星的位置和时间代码时，它可以假设它位于地球表面并获得良好的读数。 如果您不在地面并且还想要高度，则需要 4 颗卫星。
AGPS
正如您在上面看到的，使用普通 GPS 可能需要很长时间才能获得定位。 有多种方法可以加快速度，但除非您始终随身携带原子钟，或者始终保持 GPS 开启状态，否则在您获得时钟之前总会有 5-60 秒的延迟。地点。
为了节省成本，大多数手机与蜂窝组件共享 GPS 接收器组件，并且您无法同时进行修复和通话。 人们不喜欢这样（特别是在发生紧急情况时），因此最低形式的 GPS 会执行以下操作：
这在电话设计上节省了大量资金，但它对蜂窝带宽的负载很大，并且随着大量请求的到来，它需要大量快速服务器。 不过，总体而言，实施起来会更便宜、更快。 然而，由于这种负载，他们不愿意在这些手机上发布基于 GPS 的功能 - 所以你不会在这里看到逐向导航。
最近的设计包括完整的 GPS 芯片。 他们仍然从电话公司获取数据 - 例如基于塔定位的当前位置和当前卫星位置 - 这提供了不到 1 秒的定位时间。 这些信息只需要一次，GPS 可以用很少的电量跟踪此后的所有信息。 如果蜂窝网络不可用，那么他们仍然可以在一段时间后获得修复。 如果接收器看不到 GPS 卫星，那么它们仍然可以从蜂窝塔获得粗略的定位。
但要完全回答你的问题 - 它是免费的，就像电话公司所说的那样，到目前为止他们根本不收费。 我怀疑这种情况将来会改变。 在带有完整 GPS 接收器的高端手机中，您甚至可以加载自己的软件并访问它，例如在摩托罗拉 iDen 手机上使用 mologogo - J2ME 开发套件是免费的，而手机只需 40 美元（预付费手机） 5 美元信用）。 无限上网费用约为每月 10 美元，因此只要 40 美元起价，每月 10 美元，您就可以获得互联网跟踪系统。 （价格大约 2008 年 8 月）
从现在开始，它只会变得更便宜、功能更齐全...
回复：Google 地图等 是
的，Google 地图和所有其他手机地图系统在不同时间都需要某种数据连接使用过程中。 例如，当您朝一个方向移动足够远时，它会向服务器请求新的图块。 您的普通手机没有足够的存储空间来保存美国地图，也没有足够的处理器能力来很好地呈现它。 如果你想将存储空间与地图一起使用，iPhone 就可以做到这一点，但考虑到大多数 iPhone 都有全时无限数据计划，大多数用户宁愿使用该空间来做其他事情。
GPS, the Global Positioning System run by the United States Military, is free for civilian use, though the reality is that we're paying for it with tax dollars.
However, GPS on cell phones is a bit more murky. In general, it won't cost you anything to turn on the GPS in your cell phone, but when you get a location it usually involves the cell phone company in order to get it quickly with little signal, as well as get a location when the satellites aren't visible (since the gov't requires a fix even if the satellites aren't visible for emergency 911 purposes). It uses up some cellular bandwidth. This also means that for phones without a regular GPS receiver, you cannot use the GPS at all if you don't have cell phone service.
For this reason most cell phone companies have the GPS in the phone turned off except for emergency calls and for services they sell you (such as directions).
This particular kind of GPS is called assisted GPS (AGPS), and there are several levels of assistance used.
GPS
A normal GPS receiver listens to a particular frequency for radio signals. Satellites send time coded messages at this frequency. Each satellite has an atomic clock, and sends the current exact time as well.
The GPS receiver figures out which satellites it can hear, and then starts gathering those messages. The messages include time, current satellite positions, and a few other bits of information. The message stream is slow - this is to save power, and also because all the satellites transmit on the same frequency and they're easier to pick out if they go slow. Because of this, and the amount of information needed to operate well, it can take 30-60 seconds to get a location on a regular GPS.
When it knows the position and time code of at least 3 satellites, a GPS receiver can assume it's on the earth's surface and get a good reading. 4 satellites are needed if you aren't on the ground and you want altitude as well.
AGPS
As you saw above, it can take a long time to get a position fix with a normal GPS. There are ways to speed this up, but unless you're carrying an atomic clock with you all the time, or leave the GPS on all the time, then there's always going to be a delay of between 5-60 seconds before you get a location.
In order to save cost, most cell phones share the GPS receiver components with the cellular components, and you can't get a fix and talk at the same time. People don't like that (especially when there's an emergency) so the lowest form of GPS does the following:
This saves a lot of money on the phone design, but it has a heavy load on cellular bandwidth, and with a lot of requests coming it requires a lot of fast servers. Still, overall it can be cheaper and faster to implement. They are reluctant, however, to release GPS based features on these phones due to this load - so you won't see turn by turn navigation here.
More recent designs include a full GPS chip. They still get data from the phone company - such as current location based on tower positioning, and current satellite locations - this provides sub 1 second fix times. This information is only needed once, and the GPS can keep track of everything after that with very little power. If the cellular network is unavailable, then they can still get a fix after awhile. If the GPS satellites aren't visible to the receiver, then they can still get a rough fix from the cellular towers.
But to completely answer your question - it's as free as the phone company lets it be, and so far they do not charge for it at all. I doubt that's going to change in the future. In the higher end phones with a full GPS receiver you may even be able to load your own software and access it, such as with mologogo on a motorola iDen phone - the J2ME development kit is free, and the phone is only $40 (prepaid phone with $5 credit). Unlimited internet is about $10 a month, so for $40 to start and $10 a month you can get an internet tracking system. (Prices circa August 2008)
It's only going to get cheaper and more full featured from here on out...
Re: Google maps and such
Yes, Google maps and all other cell phone mapping systems require a data connection of some sort at varying times during usage. When you move far enough in one direction, for instance, it'll request new tiles from its server. Your average phone doesn't have enough storage to hold a map of the US, nor the processor power to render it nicely. iPhone would be able to if you wanted to use the storage space up with maps, but given that most iPhones have a full time unlimited data plan most users would rather use that space for other things.