802.11a/ b/ g/ n指的是什么?

802.11a/b/g/n,指的是无线网络协议,分为802.11a、802.11b、802.11g、802.11n等。这几种不同的无线协议、都是由802.11演变而来的。主要用于解决办公室局域网和校园网中用户与用户终端的无线接入。
1、IEEE 802.11b是无线局域网的一个标准。其载波的频率为2.4GHz,可提供1、2、5.5及11Mbit/s的多重传送速度。

2、IEEE 802.11g在2003年7月被通过。其载波的频率为2.4GHz(跟802.11b相同),原始传送速度为54Mbit/s,净传输速度约为24.7Mbit/s(跟802.11a相同)。802.11g的设备向下与802.11b兼容。

3、IEEE 802.11n,是2004年1月时IEEE宣布组成一个新的单位来发展的新的802.11标准,在市面上零售的相关产品版本为草拟版本2.0。传输速度理论值为300Mbit/s,因此需要在物理层产生更高速度的传输率,此项新标准应该要比802.11b快上50倍,而比802.11g快上10倍左右。
在这里插入图片描述
拓展资料:

通常我们将Wi-Fi的802.11标准分为5代,简单的差异为:

第一代802.11,1997年制定,原始标准,工作在2.4GHz,最快2Mbit/s。

第二代802.11b,1999年,工作在2.4GHz,最快11Mbit/s,正逐渐淘汰。

第三代802.11g/a,2003年,工作在2.4GHz和5GHz,最快54Mbit/s。

第四代802.11n,2009年9月通过正式标准,工作在2.4GHz或5GHz,传输速率提高达350Mbps,甚至能到600Mbps。

第五代802.11ac,只使用5GHz,理论上可以提供高达每秒1Gbit的数据传输能力。

### IEEE 802.11a Wireless Standard Specifications and Usage #### Overview of IEEE 802.11a The IEEE 802.11a standard was introduced as an amendment to the original 802.11 protocol, aiming to enhance wireless network performance through higher frequency bands and advanced modulation techniques[^4]. It operates within the 5 GHz spectrum band, which provides more available channels compared to the crowded 2.4 GHz band used by earlier standards like 802.11b. #### Key Features and Technical Details One significant feature of 802.11a is its utilization of Orthogonal Frequency Division Multiplexing (OFDM), enabling it to achieve maximum data rates up to 54 Mbps under ideal conditions[^5]. This technology divides the signal into multiple subcarriers that transmit simultaneously over different frequencies, reducing interference while improving overall efficiency. Additionally, operating at 5 GHz allows devices using this standard to avoid common sources of interference found in lower-frequency ranges typically occupied by household appliances or other electronic equipment. #### Compatibility & Deployment Considerations Despite offering superior speed capabilities than previous versions due partly because fewer non-WiFi gadgets operate there; however adoption faced challenges initially owing largely but not exclusively related costs associated deploying infrastructure compatible solely supporting these features without backward compatibility options until later developments were made addressing interoperability concerns between various generations including b/g/n etc.[^6] ```python # Example Python Code Demonstrating OFDM Concept Simplistically def simulate_ofdm_signal(data_chunks): """Simulates basic concept behind how OFDM works.""" modulated_signals = [] for chunk in data_chunks: # Apply some form of digital modulation per each 'subcarrier' modulated_chunk = apply_modulation(chunk) # Store result after applying transformation representing actual transmission process. transformed_result = perform_ifft(modulated_chunk) modulated_signals.append(transformed_result) combined_output = sum(modulated_signals) # Summation simulating multipath effect during real-world transmissions return combined_output def apply_modulation(binary_data): ... def perform_ifft(frequency_domain_values): ... ```
评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值