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short-range communications is one of the most relevant as well as diversified fields of en-
deavour in wireless communications. As such, it has been a subject of intense research and
development worldwide, particularly in the last decade. There is no reason to believe that this
trend will decline. On the contrary, the rapidly crystallizing vision of a hyper-connected world
will certainly strengthen the role of short-range communications in the future. Concepts such
as wireless social networks, Internet of things, car communications, home and office network-
ing, wireless grids and personal communications heavily rely on short-range communications
technology.
標(biāo)簽：
Communications
short-range
Wireless
上傳時(shí)間：
2020-06-01
上傳用戶：shancjb
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Developers, manufacturers and marketers of products incorporating short-
range radio systems are experts in their fields—security, telemetry,
medical care, to name a few. Often they add a wireless interface just to
eliminate wires on an existing wired product. They may adapt a wireless
subsystem, which is easy to integrate electrically into their system, only to
find that the range is far short of what they expected, there are frequent
false alarms, or it doesn’t work at all. It is for these adapters of wireless
subsystems that this book is primarily intended.
標(biāo)簽：
Communication
short-range
Wireless
上傳時(shí)間：
2020-06-01
上傳用戶：shancjb
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為解決輸油管道溫度壓力參數(shù)實(shí)時(shí)監(jiān)測的問題，設(shè)計(jì)了以C8051F930單片機(jī)作為控制核心的超低功耗輸油管道溫度壓力遠(yuǎn)程監(jiān)測系統(tǒng)。現(xiàn)場儀表使用高精度電橋采集數(shù)據(jù)，通過433 MHz短距離無線通信網(wǎng)絡(luò)與遠(yuǎn)程終端RTU進(jìn)行通信，RTU通過GPRS網(wǎng)絡(luò)與PC上位機(jī)進(jìn)行遠(yuǎn)程數(shù)據(jù)傳輸，在上位機(jī)中實(shí)現(xiàn)數(shù)據(jù)存儲和圖形化界面顯示，從而實(shí)現(xiàn)輸油管道溫度壓力參數(shù)的實(shí)時(shí)監(jiān)測和異常報(bào)警。經(jīng)實(shí)驗(yàn)證明，該系統(tǒng)的12位數(shù)據(jù)采集精度滿足設(shè)計(jì)要求，漏碼率小于1%，正常工作時(shí)間超過5個(gè)月，能實(shí)時(shí)有效地監(jiān)測輸油管道的溫度壓力參數(shù)，節(jié)省大量人工成本，有效預(yù)防管道參數(shù)異常造成的經(jīng)濟(jì)損失和環(huán)境污染。
Abstract:
In order to solve the problems on real-time monitoring of pipeline temperature and pressure parameters， the ultra-low power remote pipeline temperature and pressure monitoring system was designed by using the single chip processor C8051F930 as the control core. The high-precision electric bridge was used in field instruments for data collection， the 433MHz short-range wireless communication network was used to make communication between field instrument and RTU， the GPRS was used by the RTU to transmit data to the PC host computer， and the data was stored and displayed in the PC host computer， so the real-time monitoring and exception alerts of pipeline temperature and pressure parameters were achieved. The experiment proves that the system of which error rate is less than 1% over five months working with the 12-bit data acquisition accuracy can effectively monitor the pipeline temperature and pressure parameters in real time， it saves a lot of labor costs and effectively prevents environmental pollution and economic losses caused by abnormal channel parameters.
標(biāo)簽：
C8051F930
溫度
壓力
遠(yuǎn)程監(jiān)測系統(tǒng)
上傳時(shí)間：
2013-11-07
上傳用戶：cuibaigao
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The CC1101 is a low-cost sub- 1 GHztransceiver designed for very low-powerwireless applications. The circuit is mainlyintended for the ISM (Industrial, Scientific andMedical) and SRD (Short Range Device)frequency bands at 315, 433, 868, and 915MHz, but can easily be programmed foroperation at other frequencies in the 300-348MHz, 387-464 MHz and 779-928 MHz bands.CC1101 is an improved and code compatibleversion of the CC1100 RF transceiver. Themain improvements on the CC1101 include:
標(biāo)簽：
1110
CC
片上系統(tǒng)
方案
上傳時(shí)間：
2013-11-12
上傳用戶：363186
-
This manual describes Freescale’s IEEE™ 802.15.4 Standard compliant MAC/PHY software. The Freescale 802.15.4 MAC/PHY software is designed for use with the Freescale MC1319x and MC1320x, family of short range, low power, 2.4 GHz Industrial, Scientific, and Medical (ISM) band transceivers, designed for use with the HCS08 Family of MCUs. The MAC/PHY software also works with the MC1321x family of short range, low power, 2.4 GHz ISM band transceivers that incorporate a low power 2.4 GHz radio frequency transceiver and an 8-bit microcontroller into a single LGA package.
Throughout this manual, the term transceiver refers to either the MC1319x, MC1320x, or the internal counterpart inside the MC1321x System in a Package (SiP).
標(biāo)簽：
Freescale
describes
compliant
Standard
上傳時(shí)間：
2016-04-17
上傳用戶：caiiicc
-
One traditional view of how wireless networks evolve is of a continuous, inevitable progres-
sion to higher link speeds, combined with greater mobility over wider areas. This standpoint
certainly captures the development from first and second generation cellular systems focused
on voice support, and the early short-range wireless data networks, through to today’s 3G
cellular and mobile broadband systems; there is every confidence that the trend will continue
some way into the future.
標(biāo)簽：
Networks
Ambient
上傳時(shí)間：
2020-05-26
上傳用戶：shancjb
-
Over the past ten years there has been a revolution in the devel-
opment and acceptance of mobile products. In that period, cel-
lular telephony and consumer electronics have moved from the
realm of science fiction to everyday reality. Much of that revolu-
tion is unremarkable – we use wireless, in its broadest sense, for
TV remote controls, car keyfobs, travel tickets and credit card
transactions every day. At the same time, we have increased the
number of mobile devices that we carry around with us. However,
in many cases the design and function of these and other static
products are still constrained by the wired connections that they
use to transfer and share data.
標(biāo)簽：
short-range
Essentials
Wireless
of
上傳時(shí)間：
2020-05-27
上傳用戶：shancjb
-
Optical wireless communication is an emerging and dynamic research and development
area that has generated a vast number of interesting solutions to very complicated
communication challenges. For example, high data rate, high capacity and minimum
interference links for short-range communication for inter-building communication,
computer-to-computer communication, or sensor networks. At the opposite extreme is
a long-range link in the order of millions of kilometers in the new mission to Mars
and other solar system planets.
標(biāo)簽：
Communication
Wireless
Optical
Systems
上傳時(shí)間：
2020-05-31
上傳用戶：shancjb
-
Over the past ten years there has been a revolution in the devel-
opment and acceptance of mobile products. In that period, cel-
lular telephony and consumer electronics have moved from the
realm of science fiction to everyday reality. Much of that revolu-
tion is unremarkable – we use wireless, in its broadest sense, for
TV remote controls, car keyfobs, travel tickets and credit card
transactions every day.
標(biāo)簽：
short-range
Wireless
上傳時(shí)間：
2020-06-01
上傳用戶：shancjb
-
Ultra-wideband (UWB) technology enables high data-rate short-range communica-
tion, in excess of hundredmegabit-per-secondsand up to multi-gigabit-per-seconds,
over a wide spectrum of frequencies, while keeping power consumption at low lev-
els. This low power operation results in a less-interfering co-existence with other
existed communication technologies (e.g., UNII bands).
In addition to carrying a huge amount of data over a distance of up to 230 feet
at very low power (less than 0.5mW), the UWB signal has the ability to penetrate
through the doors and other obstacles that tend to reflect signals at more limited
bandwidths and higher power densities.
標(biāo)簽：
Silicon-Based
Front-Ends
RF
上傳時(shí)間：
2020-06-01
上傳用戶：shancjb
